SCIENTIFIC
WORKING GROUP FOR THE
ANALYSIS OF
SEIZED DRUGS (SWGDRUG)
RECOMMENDATIONS
RECOMMENDATIONS
INCLUDE:
CODE OF PROFESSIONAL PRACTICE
EDUCATION and TRAINING
METHODS OF ANALYSIS
QUALITY ASSURANCE
UNITED
STATES DEPARTMENT OF JUSTICE
DRUG
ENFORCEMENT ADMINISTRATION
EXECUTIVE
OFFICE OF THE PRESIDENT
OFFICE
OF NATIONAL DRUG CONTROL POLICY
COUNTERDRUG
TECHNOLOGY ASSESMENT CENTER
Version
7.1, 2016-June-9
PDF Disclaimer |
This
PDF file may contain embedded typefaces.
In accordance with Adobe’s licensing policy, this file may be printed
or viewed but shall not be edited unless the typefaces which are embedded are
licensed to and installed on the computer performing the editing. In downloading this file, parties accept
therein the responsibility of not infringing Adobe’s licensing policy. The SWGDRUG Secretariat accepts no
liability in this area. Adobe
is a trademark of Adobe Systems Incorporated. Details
of the software products used to create this PDF file can be found in the
General Info relative to the file; the PDF-creation parameters were optimized
for printing. Every care has been
taken to ensure that the file is suitable for use by interested parties. In the unlikely event that a problem
relating to it is found, please inform the SWGDRUG Secretariat at the address
given below. |
©
SWGDRUG 2016-June-9
All
rights reserved. Unless otherwise
specified, this publication may be reproduced and/or utilized in any form or by
any means, electronic or mechanical, including photocopying and microfilm.
E-mail swgdrug@hotmail.com
Web www.swgdrug.org
Contents Page
Foreword……………………………………………………………………………………. vi
Introduction………………………………..……………………………………………...… vii
Core committee…………………………………………………………………………….. viii
PART I - A
Code of Professional Practice for Drug Analysts
1 Introduction……………………………………….....……………………………… 1
2 Code of professional practice…………………………………………………….. 1
2.1 Professional conduct……………………………………………………………… 2
2.2 Casework……………………………………………………………………………. 2
2.3 Reporting………………...………………………………………………………….. 3
PART II - Education and
Training
1 Introduction..…………………………………………………………...…………… 4
2 Education and experience for analysts………………………………………….. 4
3 Continuing professional development……………………………………………. 4
4 Initial training requirements……………………………………………………….. 5
5 References and documents……………………………………………………..... 6
PART III - Methods of
Analysis
PART III A -
Methods of Analysis/Sampling Seized Drugs for Qualitative Analysis
1 Introduction……………………………………………………………………...….. 7
2 Sampling strategy………………………………………………………………….. 8
3 Sampling scheme………………………………………………………………..… 8
3.1 Population determination………………………………………………………….. 9
3.2 Sampling plan………………………………………………………………………. 10
3.3 Sampling procedure………………………………………………..……………… 11
3.4 Sample reduction…………………………………………………………………... 12
4 Analysis……………………………………………………………………………... 12
4.1 Statistically selected sample(s)…………………………………………………… 12
4.2 Non-statistically selected sample(s)……………………………………………… 12
5 Documentation……………………………………………………………………... 13
6 Reporting……………………………………………………………………………. 13
PART III B -
Methods of Analysis/Drug Identification
1 Introduction……………………………………………………………………...….. 14
2 Categorizing analytical techniques……………………………….………………. 14
3 Identification criteria………………………………………………...……………… 15
4 Comment……………………………………………………………………………. 16
PART III C – Methods of
Analysis/Clandestine Laboratory Evidence
1 Introduction................................................................................................................. 17
2 Safety .......................................................................................................................... 17
3 Sample selection for analysis................................................................................. 19
4 Analysis....................................................................................................................... 19
5 Yield and capacity calculations.............................................................................. 22
6 Reports and conclusions......................................................................................... 23
7 Training....................................................................................................................... 24
PART III D – Methods of
Analysis/Analogue and Structural Class Determinations
1 Introduction……………………………………………………………………...….. 26
2 Analogues…………………………………………….…………………………….. 26
3 Structural Class Determinations………………………………………………..... 27
4 Reporting……………………………………………………………………………. 28
PART IV - Quality
Assurance
PART IV A -
Quality Assurance/General Practices
1 Introduction……………………………………………………………………...….. 29
2 Quality management system…………………………………………….……….. 29
3 Personnel………………………………………………………………………….... 29
3.1 Job description……………………………………………………………………... 29
3.2 Designated personnel and responsibilities……………………………………… 29
3.3 Qualification/Education……………………………………………………………. 30
3.4 Initial training requirements…………………………………………………..…… 31
3.5 Maintaining competence……………………………………………..…………….31
4 Physical plant…………………………………………………………………….…. 31
5 Evidence control………………………………………………………………..….. 31
5.1 Receiving and identifying evidence……………………………………….……… 32
5.2 Integrity of evidence…………………………………………………………….…. 32
5.3 Storage of evidence…………………………………………………………….….. 32
5.4 Disposition of evidence……………………………………………………………. 32
5.5 Documentation retention procedures………………………………………….…. 32
6 Analytical procedures………………………………………………………..…….. 33
6.1 Analytical procedures for drug
analysis…………………………………….……. 33
6.2 Assessment of drug reference materials………………………………………. 34
7 Instrument/Equipment performance……………………………………..………. 37
7.1 Instrument performance…………………………………………………………… 37
7.2 Equipment…………………………………………………………………..………. 37
8 Chemicals and reagents……………………………………………………..……. 38
9 Casework documentation, report
writing and review…………………………… 38
9.1 Casework documentation…………………………………………………………. 38
9.2 Report writing……………………………………………………………………….. 38
9.3 Case review………………………………………………………………………… 39
10 Proficiency and competency testing…………………………………………..…. 39
10.1 Proficiency testing………………………………………………………………….. 39
10.2 Competency testing……………………………………………………………..…. 40
11 Analytical method validation and
verification……………………………………. 40
12 Laboratory audits…………………………………………………………………… 40
13 Deficiency of analysis……………………………………………………………… 40
14 Health and safety……………………………………………………………….….. 41
14.1 Health and safety requirements……………………………………………….….. 41
15 Additional documentation…………………………………………………….…… 42
PART IV B -
Quality Assurance/Validation of Analytical Methods
1 Introduction……………………………………………………………………...….. 43
1.1 Definition and purpose of validation……………………………………...………. 43
1.2 Analytical scheme………………………………………………………………….. 43
1.3 Individual laboratory responsibility……………………………………………….. 43
1.4 Operational environment………………………………………………………….. 43
1.5 Documentation……………………………………………………………………... 44
1.6 Recommendation…………………………………………………………………... 44
2 General validation plan……………………………………………………………. 44
2.1 Purpose/scope……………………………………………………………………… 44
2.2 Analytical method…………………………………………………………………... 44
2.3 Reference materials……………………………………………………………….. 45
2.4 Performance characteristics………………………………………………………. 45
3 Quality control………………………………………………………………………. 48
4 References………………………………………………………………………….. 48
PART IV C – Quality
Assurance/Uncertainty
1 Introduction…………………………………………………………………………. 49
2 Qualitative analysis………………………………………………………………… 50
3 Quantitative measurements………………………………………………………. 50
4 Estimation of measurement uncertainty
for quantitative determinations…….. 51
4.1 Sources of uncertainty for weight
determinations………………………………. 51
4.2 Sources of uncertainty for purity
determinations……………………………….. 51
4.3 Factors relevant to estimation of
measurement uncertainty…………………... 52
4.4 Approaches for estimation of
measurement uncertainty………………………. 52
5 Reporting of uncertainty…………………………………………………………… 53
5.1 Reporting……………………………………………………………………………. 54
5.2 Reporting Examples……………………………………………………………….. 54
6 Training……………………………………………………………………………… 55
7 References………………………………………………………………………….. 56
Annex A - SWGDRUG Glossary of Terms and Definitions……………………………. 58
Bibliography………………...……………………….…………………………………..….. 68
This
publication contains recommendations from the Scientific Working Group for the
Analysis of Seized Drugs (SWGDRUG).
These recommendations are intended to assist forensic analysts and
managers in the development of analytical techniques, protocols and
policies. They are recognized to be
minimum standards that may be modified to address unique jurisdictional
requirements. SWGDRUG seeks to have these recommendations internationally
accepted as the foundation for good laboratory practice. These recommendations encompass Code of
Professional Practice, Education and Training, Methods of Analysis and Quality
Assurance. The SWGDRUG Core Committee
strongly urges the adoption of these recommendations by any laboratory involved
in the analysis of seized drugs.
Since 1997,
SWGDRUG has been working to provide useful and practical recommendations for
the analysis of seized drugs. SWGDRUG
recognizes that over time these recommendations may need to be updated as a
result of advances in technology, changes in accreditation requirements and/or
the emergence of new requirements. To
this end, SWGDRUG relies heavily on the input of the forensic community to
ensure that all recommendations remain useful and current. This synergetic approach is a key component
of the SWGDRUG process. I encourage
everyone to continue supporting the mission of SWGDRUG.
Finally, as
the Chair of SWGDRUG, I would be remiss if I did not single out several
individuals without whom SWGDRUG would not exist. Benjamin A. Perillo
conceived this working group and made it a reality. As former Chairs of SWGDRUG, Thomas J. Janovsky and Nelson A. Santos promoted and enhanced SWGDRUG’s
prominence in the forensic community.
Lastly, I recognize Sandra E. Rodriguez-Cruz, Secretariat, for her
untiring efforts in coordinating and facilitating the SWGDRUG meetings.
I would also
like to make special mention to the Drug Enforcement Administration, the Office
of National Drug Control Policy and the National Institute of Standards and
Technology, which over the years have provided the financial resources for
SWGDRUG to operate.
Introduction
SWGDRUG
is comprised of a core committee of approximately
20 members from around the world.
Mission Statement:
SWGDRUG works
to improve the quality of the forensic examination of seized drugs and to respond
to the needs of the forensic community by supporting the development of
internationally accepted minimum standards, identifying best practices within
the international community, and providing resources to help laboratories meet
these standards.
SWGDRUG
seeks to achieve this mission through the following objectives:
·
specifying
requirements for practitioners’ knowledge, skills and abilities,
·
promoting
professional development,
·
providing
a means of information exchange within the
forensic science community,
·
promoting
ethical standards of practitioners,
·
recommending
minimum standards for examinations and reporting,
·
providing
resources and tools,
·
establishing
quality assurance requirements,
·
considering
relevant international standards, and
·
seeking
international acceptance of SWGDRUG recommendations.
Drug
abuse and trafficking in controlled substances are global problems, and
law enforcement has looked to international solutions
for these problems. In 1997 the U.S.
Drug Enforcement Administration (DEA) and the Office of National Drug Control
Policy (ONDCP) co-sponsored the formation of the Technical Working Group for
the Analysis of Seized Drugs (TWGDRUG).
Forensic scientists from the United States, England, Canada, Australia,
Japan, Germany and the Netherlands, as well as representatives of the United
Nations, several international forensic organizations and academia were invited
to meet in Washington, DC. This group,
with input from around the world, developed educational and professional
development recommendations for forensic
practitioners. They also developed quality
assurance and identification recommendations for seized drugs. The name
Scientific Working Group for the Analysis of Seized Drugs was adopted in 1999.
SWGDRUG
has received input from many members
of the forensic community in its recommendations development process.
It has used various methods of communication including its Internet site
(www.swgdrug.org), presentations at
numerous local, national and international meetings, and personal contacts. Following each meeting of the Core Committee,
updates are published and distributed.
SWGDRUG
sought and considered comments from the forensic science community on all its
proposals. In order for a recommendation
to be adopted, there are
specific procedures that must be met.
Please refer to the SWGDRUG’s bylaws, which can be found on the internet at www.swgdrug.org/bylaws.htm for additional details. In addition, SWGDRUG has submitted its
recommendations to ASTM International, a standards developing organization,
resulting in seven published standards:
Standard
Practice for Education and Training for Seized-Drug Analysts |
|
Standard
Practice for Quality Assurance of Laboratories Performing Seized-Drug
Analysis |
|
Standard
Practice for Identification of Seized Drugs |
|
Standard
Guide for Sampling Seized Drugs for Qualitative and Quantitative Analysis |
|
Standard
Practice for Validation of Seized-Drug Analytical Methods |
|
Standard
Practice for Uncertainty Assessment in the Context of Seized-Drug Analysis |
|
Standard
Guide for Analysis of Clandestine Drug Laboratory Evidence |
In July 2010
the leadership of SWGDRUG was transferred to Scott R. Oulton, Chair and Sandra
E. Rodriguez-Cruz, Secretariat. The various sub-committees continue to
research and develop proposals for additional recommendations with several
members completing their service to the group and
others replacing them by invitation.
The following chart details those persons who have
rendered service as members of the core committee over the years. Current core committee members are indicated in bold
text. A list of current members is also available on the SWGDRUG
website.
PART I
A CODE OF PROFESSIONAL
PRACTICE FOR DRUG ANALYSTS
PREFACE
This Code of Professional Practice has been written specifically for
analysts. However, it is important that their managers and the
technicians and others who assist them in their work are equally aware of its
provisions, and they support the analyst in adhering to these. Where
appropriate, the provisions are also equally applicable to the technicians in
the approach to their own work.
I.1.1
A Code of Professional Practice is intended to provide the
framework of ethical values and scientific and legal obligations within which
the analyst should operate. Details are also usually provided on how
alleged breaches of the Code will be investigated, what sanctions are available
and how appeals should be pursued.
I.1.2
A Code of Professional Practice is essential to analysts and their
managers in helping them carry out their duties in a proper manner and in
making appropriate decisions when questions of ethics arise.
I.1.3
A Code of Professional Practice that is enforced and publicly
available is also a powerful means of demonstrating the professional
expectations of analysts and the reliability of their findings to others in the
criminal justice system and the public at large.
I.1.4
SWGDRUG recommends that all employers of analysts develop a Code
of Professional Practice and the means of dealing with breaches of the
Code.
I.1.5
SWGDRUG further recommends that all Codes of Professional Practice
for analysts should include, as a minimum, provisions relating to their
professional conduct, their casework and the reporting of their results, as
provided in Section 2. For further information, see Supplemental Document SD-1 (Examples for Part I - A Code of
Professional Practice for Drug Analysts).
I.2
Code of professional practice
I.2.1
Professional conduct
Analysts shall:
a) act with honesty, integrity and objectivity;
b) work only within the bounds of their professional
competence;
c) take reasonable steps to maintain their competence;
d) recognize that their overriding duty is to criminal justice;
e) declare to their employer any prior contact or
personal involvement, which may give rise to conflict of interest, real
or perceived;
f) declare to their employer or other appropriate authority
any pressure intended to influence the result of an examination.
I.2.2 Casework
Analysts shall:
a) strive
to demonstrate that the integrity and security of
evidential materials and the information derived from their analysis have been
maintained while in their possession;
b) strive
to have a clear understanding of what the customer
needs and all the necessary information, relevant evidential materials and
facilities available to reach a meaningful conclusion in an appropriate
timeframe;
c) employ an appropriate analytical approach, using the
facilities available;
d) make and retain full, contemporaneous, clear and accurate
records of all examinations and tests conducted, and conclusions drawn, in
sufficient detail to allow meaningful review and assessment of the conclusions
by an independent person competent in the field;
e) accept responsibility for all casework done by themselves
and under their direction;
f) conduct all professional activities in a way that protects
the health and safety of themselves, co-workers, the public and the
environment.
I.2.3 Reporting
Analysts shall:
a) present advice and testimony, whether written or oral, in an objective
manner;
b) be prepared to reconsider and, if necessary, change their
conclusions, advice or testimony in light of new information or developments,
and take the initiative in informing their employer and customers promptly of
any such changes that need to be made;
c) take appropriate action if there is potential for, or there
has been, a miscarriage of justice due to new circumstances that have come to
light, incompetent practice or malpractice;
d) preserve customer confidentiality unless officially
authorized to do otherwise.
PART II
EDUCATION AND TRAINING
Part
II recommends minimum education, training and experience for analysts
practicing in laboratories that conduct seized drug analyses. It describes the types of activities
necessary to continue professional development and reference literature
required in laboratories where they practice.
II.1.1
Recommendations listed in Part II are intended to apply
to any analyst who:
a) independently
has access to unsealed evidential material in order to remove samples for
examination;
b) examines
and analyzes seized drugs or related materials, or directs such examinations to
be done; and
c) as a consequence of such examinations,
signs reports for court or investigative purposes.
II.2
Education and
experience for analysts
All new analysts shall have at least a bachelor’s
degree or equivalent (generally, a three to four year post-secondary degree) in
a natural/physical science. The individual shall have successfully completed
lecture and associated laboratory classes in general, organic and analytical
chemistry.
II.3
Continuing
professional development
All
forensic scientists have an ongoing responsibility to remain current in their
field. In addition, laboratories shall
provide support and opportunities for continuing professional development. Minimum continuing professional development
requirements for a laboratory analyst are:
II.3.1
Twenty hours of training every year.
II.3.2
Training shall be relevant to the laboratory's mission. Professional development may include training
related to ancillary duty assignments and supervision/management
responsibilities.
II.3.3
Training shall be documented.
II.3.4
Training can be face-to-face interaction with an
instructor, distance learning, self-directed or computer based. Training can be
provided from a variety of sources, including, but not limited to the
following:
·
chemistry
or instrumental courses taught at the post-secondary educational level
·
instrument
operation or maintenance courses taught by vendors
·
in-service
classes conducted by the employer
·
current
literature review
·
in-service
training taught by external providers
·
participation
in relevant scientific meetings or conferences (e.g., delivering an oral or
poster presentation, attending a workshop, providing reports on conferences).
II.4
Initial training
requirements
These
minimum requirements allow individual laboratories to structure their training
program to meet their needs as it relates to type of casework encountered,
analytical techniques, available instrumentation and level of preparedness of
trainees.
II.4.1
There shall be a documented training program, approved by
laboratory management that focuses on the development of theoretical and
practical knowledge, skills and abilities necessary to examine seized drug
samples and related materials. The
training program shall include the following:
a) documented standards of performance and
a plan for assessing theoretical and practical competency against these
standards (e.g., written and oral examinations, critical reviews, analysis of
unknown samples and mock casework per topic area);
b) a training syllabus providing
descriptions of the required knowledge and skills in specific topic areas in
which the analyst is to be trained, milestones of achievement, and methods of
testing or evaluating competency;
c) a period of supervised casework representative
of the type the analyst will be required to perform;
d) a verification document demonstrating
that the analyst has achieved the required competence.
II.4.2
Topic areas in the training program shall include, as a
minimum, the following:
·
relevant
background information on drugs of abuse (e.g., status of control and chemical
and physical characteristics)
·
techniques,
methodologies and instrumentation utilized in the examination of seized drug
samples and related materials
·
quality
assurance
·
ethics
·
expert/court
testimony and legal requirements
·
laboratory
policy and procedures (e.g., sampling, uncertainty, evidence handling, safety
and security) as they relate to the examination of seized drug samples and
related materials.
II.4.3
SWGDRUG endorses the ENFSI Drug Working Group document “Education and Training
Outline for Forensic Drug Practitioners” and recommends its use in the development
of training programs.
II.4.4
An individual qualified to provide instruction shall have
demonstrated competence in the subject area and in the delivery of training.
The following references and documents shall
be available and accessible to analysts.
a) college/university level textbooks for
reference to theory and practice in key subject areas, e.g., general chemistry,
organic chemistry and analytical chemistry
b) reference literature containing
physical, chemical and analytical data.
Such references include the Merck
Index, Clarke’s Analysis of Drugs and
Poisons, laboratory manuals of the United Nations Drug Control Program,
in-house produced spectra and published standard spectra, (e.g., Mills and
Roberson’s Instrumental Data For Drug
Analysis, or compendia from Pfleger or Wiley)
c) operation
and maintenance manuals for each analytical instrument
d) relevant periodicals (e.g., Journal of
Forensic Sciences, Forensic Science
International, Microgram, Journal of Canadian Society of Forensic Science, Japanese Journal of Forensic Science
and Technology, Science & Justice, Drug
Testing and Analysis)
e) laboratory quality manual, standard
operating procedures, and method validation and verification documents
f) relevant jurisdictional legislation
(e.g., statutes and case law relating to controlled substances, and health and
safety legislation)
PART III A
METHODS OF
ANALYSIS/SAMPLING SEIZED DRUGS
FOR QUALITATIVE ANALYSIS
This document
addresses minimum recommendations for sampling of seized drugs for qualitative
analysis.
NOTE For the purpose of this document the use of
the term “statistical” refers to “probability-based.”
IIIA.1.1
The
principal purpose of sampling in the context of this recommendation is to
answer relevant questions about a population by examination of a portion of the
population (e.g., What is the net weight of the population? What portion of the
units of a population can be said to contain a given drug at a given level of
confidence?)
IIIA.1.2
By
developing a sampling strategy and implementing appropriate sampling schemes,
as illustrated in Figure 1, a laboratory will minimize the total number of
required analytical determinations, while assuring that all relevant legal and
scientific requirements are met.
Figure 1: Relationship of the Various Levels Required in Sampling
An
appropriate sampling strategy is highly dependent on the purpose of the
investigation, the customer’s request, and the anticipated use of the results. Laws and legal practices form the foundation
of most strategies and shall be taken into account when designing a sampling
scheme. Therefore, specific sampling
strategies are not defined in this document.
IIIA.2.1
The
laboratory has the responsibility to develop its own strategies consistent with
these recommendations. SWGDRUG
recommends attention to the following key points:
IIIA.2.1.1
Sampling
may be statistical or non-statistical.
IIIA.2.1.1.1 In many cases, a non-statistical
approach may suffice. The sampling plan
shall provide an adequate basis for answering questions of applicable law
(e.g., Is there a drug present in the population? Are statutory enhancement
levels satisfied by the analysis of a specified number of units?)
IIIA.2.1.1.2 If an inference about the whole
population is to be drawn from a sample, then the plan shall be either statistically based or
have an appropriate statistical analysis completed and limits of the
inference shall be documented.
IIIA.2.1.2 Each selected sample shall
be analyzed to meet the SWGDRUG minimum recommendations for forensic drug
identification (see Part III B – Drug Identification) if statistical inferences are to be made
about the chemical identity of a population.
IIIA.3
Sampling scheme
The sampling scheme
is an overall approach which includes population determination, selection of
the sampling plan and procedure and, when appropriate, sample reduction prior
to analysis (Figure 2).
Insert A
Figure 2: Example of a Sampling Scheme - A Decision
Flowchart
IIIA.3.1
Population determination
IIIA.3.1.1
The
population determination shall take into account all typical forms and
quantities in which exhibits may appear.
IIIA.3.1.2
A
population can consist of a single unit or multiple units.
IIIA.3.1.3
A
multiple unit population shall consist of items, which are similar in relevant
visual characteristics (size, color, shape, etc.).
IIIA.3.2
Sampling plan
There
are numerous sampling plans used in the forensic analysis of drugs that are applicable to single and multiple unit
populations.
IIIA.3.2.1
When
a single unit or bulk population is to be analyzed, the issue of homogeneity
shall be addressed within the sampling plan.
IIIA.3.2.1.1 One sample is sufficient if the bulk
material is homogeneous, or if it is made so by the analyst.
IIIA.3.2.1.2 If the bulk material is not
homogeneous, several samples from different locations may be necessary to
ensure that the test results are representative of the bulk material and to
avoid false negative results.
IIIA.3.2.2
For a multiple
unit population, the sampling plan may be statistical or non-statistical.
IIIA.3.2.2.1 Statistical approaches are applicable
when inferences are made about the whole population. For example:
a) The
probability that a given percentage of the population contains the drug of
interest or is positive for a given characteristic.
b) The
total net weight of the population is to be extrapolated from the average weight of individual
sample units.
Published examples are provided below:
·
Frequentist
o
Hypergeometric
§
Frank
et al., Journal of Forensic Sciences, 1991, 36(2) 350-357
§
Guidelines on Representative Drug
Sampling,
European Network of Forensic Science Institutes (ENFSI), 2009, www.enfsi.eu
§
American
Society for Testing and Materials (ASTM) E-2334
o
Other
probability based approaches
§
ASTM E105 “Standard Practice for Probability
Sampling of Materials”
§
ASTM E122 “Standard Practice for Calculating
Sample Size to Estimate, With a Specified Tolerable Error, the Average for a
Characteristic of a Lot or Process”
§
Guidelines on Representative Drug
Sampling,
ENFSI, 2009, www.enfsi.eu
·
Bayesian
o
Coulson
et al., Journal of Forensic Sciences, 2001, 46(6) 1456-1461
o
Guidelines on Representative Drug
Sampling,
ENFSI, 2009, www.enfsi.eu
IIIA.3.2.2.2 Non-statistical approaches
are appropriate if no inference is to be made about the whole population.
IIIA.3.2.2.3 A non-statistical sampling
approach may allow an inference on the population. If the population has been randomly sampled, the
data may allow an inference to be drawn by:
§
determining and reporting a confidence interval for an inferred population
parameter (e.g. weight or tablet count).
§
Retrospectively using the results in a statistical model and
determining the resulting probabilities and level of confidence.
IIIA.3.2.2.4 If a non-random sampling
plan has been used, then no inference shall be made.
Examples of non-statistical approaches are:
·
The
“square root” method
o
Recommended Methods for Testing Opium,
Morphine and Heroin: Manual for Use by National Drug Testing Laboratories, United Nations Office on Drugs and
Crime, 1998
·
Guidelines on Representative Drug
Sampling, ENFSI,
2009, www.enfsi.eu
·
Selection
of a single unit from a multiple unit population. This may be appropriate under certain
circumstances (e.g., management directives, legislative and/or judicial
requirements).
IIIA.3.3.1
Establish
the procedure for selecting the number of units that will comprise the sample.
IIIA.3.3.1.1 For non-statistical approaches select
a sample appropriate for the analytical objectives.
IIIA.3.3.1.2 For statistical approaches, a random
sampling shall be conducted.
IIIA.3.3.2
Select
a random sample.
IIIA.3.3.2.1 A random sample is one selected
without bias. Computer generated random
numbers or random number tables are commonly employed for such tasks and these
should be included in the sampling plan.
IIIA.3.3.2.2 Random sampling of items using random
number tables may not be practical in all cases. In these instances, an alternate sampling
plan shall be designed and documented to approach random selection. A practical solution involves a “black box”
method, which refers to one that will prevent the sampler from consciously
selecting a specific item from the population (e.g., all units are placed in a
box and the samples for testing are selected without bias). Random sampling is discussed in the following
references:
·
ASTM E105
“Standard Practice for Probability Sampling of Materials”
·
Guidelines on Representative Drug Sampling, ENFSI, 2009, “Chapter 4:
Arbitrary Sampling ”, pages 9-10; www.enfsi.eu
Sample
reduction may be applied in cases where the weight or volume of the selected
units is too large for laboratory analysis (Figure 2, insert A).
IIIA.4.1
Statistically selected sample(s)
If statistical inferences are to be made about the chemical identity
of a population, each selected sample shall be analyzed to meet the SWGDRUG
minimum recommendations for forensic drug identification (see Part III B –
Drug Identification).
IIIA.4.2
Non-statistically selected sample(s)
SWGDRUG
minimum recommendations for forensic drug identification (see Part III B – Drug
Identification) shall
be applied to at least one unit of the sample.
Inferences
drawn from the application of the sampling plan and subsequent analyses shall
be documented.
Sampling
information shall be included in reports (see Part
IVA – Report Writing).
IIIA.6.1
Statistically selected sample(s)
Reporting
statistical inferences for a population is acceptable when testing is performed
on the statistically selected units as stated in Section 4.1 above. The language in the report must make it clear to the
reader that the results are based on a sampling plan.
IIIA.6.2
Non-statistically selected sample(s)
The language in the report must make it clear
to the reader that the results apply to only the tested units. For example, 2 of 100 bags were analyzed and
found to contain Cocaine.
METHODS OF ANALYSIS/DRUG
IDENTIFICATION
The purpose
of PART III B is to recommend minimum standards for the forensic identification
of commonly seized drugs. It is
recognized that the correct identification of a drug or chemical depends on the
use of an analytical scheme based on validated methods (see PART
IV B – Validation)
and the competence of the analyst. It is
expected that, in the absence of unforeseen circumstances, an appropriate
analytical scheme effectively results in no uncertainty in reported identifications
(see PART
IV C – Uncertainty). SWGDRUG requires the use of multiple uncorrelated
techniques. It does not discourage the use of any
particular method within an analytical scheme and it is accepted that unique
requirements in different jurisdictions may dictate the practices followed by a
particular laboratory.
Techniques
for the analysis of drug samples are classified into three categories (see
Table 1) based on their maximum potential discriminating power. However, the classification of a technique
may be lower, if the sample, analyte or mode of operation diminishes its
discriminating power.
Examples of
diminished discriminating power may include:
§ an infrared spectroscopy technique
applied to a mixture which produces a combined spectrum
§ a mass spectrometry technique which
only produces molecular weight information
Table
1: Categories of Analytical Techniques
Category
A |
Category
B |
Category
C |
Infrared Spectroscopy |
Capillary Electrophoresis |
Color Tests |
Mass Spectrometry |
Gas Chromatography |
Fluorescence Spectroscopy |
Nuclear Magnetic Resonance Spectroscopy |
Ion Mobility Spectrometry |
Immunoassay |
Raman Spectroscopy |
Liquid Chromatography |
Melting Point |
X-ray Diffractometry |
Microcrystalline Tests |
Ultraviolet Spectroscopy |
|
Pharmaceutical Identifiers |
|
|
Thin Layer Chromatography |
|
|
Cannabis only: Macroscopic Examination Microscopic Examination |
|
IIIB.3 Identification
criteria
SWGDRUG recommends that laboratories
adhere to the following minimum standards:
IIIB.3.1
When
a validated Category A technique is incorporated into an analytical scheme, at
least one other technique (from either Category A, B or C) shall be used.
IIIB.3.2
When
a Category A technique is not used, at least three different validated
techniques shall be employed. Two of the three techniques shall be based on
uncorrelated techniques from Category B.
IIIB.3.2.1 For cannabis, macroscopic and
microscopic examinations will be considered as uncorrelated techniques from
Category B when observations include documented details of botanical
features. Laboratories shall define the
acceptance criteria for these features for each examination.
IIIB.3.2.2 For exhibits of cannabis that lack
sufficient observable macroscopic and microscopic botanical detail (e.g.
extracts or residues), D9-tetrahydrocannabinol
(THC) or other cannabinoids shall be identified utilizing the principles set
forth in sections 3.1 and 3.2.
IIIB.3.3
Botanists may identify cannabis and other
botanical material utilizing morphological characteristics (category B) alone provided sufficient botanical
features appropriate for identification are observed. Such examinations shall be made only by
analysts competent in botanical identifications. In this context botanical competence applies
to those examiners recognized as professional botanists or those assessed to be
competent by such. Identifications of chemical components contained in
botanicals (mescaline, opiates, psilocin, etc.) should rely on principles set
forth in sections 3.1 and 3.2.
IIIB.3.4
All
Category A and botanical identifications shall have data that are reviewable.
Where a Category A technique is not used, the requirement for reviewable data
applies to category B techniques. Examples
of reviewable data are
·
printed
spectra, chromatograms, digital images, photographs or photocopies (color,
where appropriate) of TLC plates
·
contemporaneous
documented peer review for microcrystalline tests
·
reference
to published data for pharmaceutical identifiers
·
For cannabis and botanical materials
only: recording of detailed descriptions of morphological characteristics.
IIIB.3.5
For
the use of any method to be considered of value, test results shall be
considered “positive” (i.e., it must meet the acceptance criteria defined in
the method validation and operating protocol). When possible, data from a test result should
be compared to data generated from a reference material which has been analyzed
under the same analytical conditions (see PART
IV A - Assessment of Drug Reference
Materials). While “negative” test results provide
useful information for ruling out the presence of a particular drug or drug
class, these results have no value toward establishing the forensic
identification of a drug.
IIIB.3.6
The
laboratory shall employ quality assurance measures to ensure the results
correspond to the exhibit. Example measures are:
·
the
use of two separate samplings
·
sample
identification procedures such as bar-coding and witness checks
·
good
laboratory practices (e.g., positive and negative controls, one sample opened
at a time, procedural blanks)
IIIB.3.7
In
cases where hyphenated techniques are used (e.g. gas chromatography-mass
spectrometry, liquid chromatography-diode array ultraviolet spectroscopy), they
will be considered as separate techniques provided that the results from each
are used.
IIIB.3.8
The
chosen analytical scheme shall demonstrate the identity of the specific drug
present and shall preclude a false positive identification and minimize false
negatives. Where a scheme has limitations, this shall be reflected in the final
interpretation (see Part IVC.2 – Qualitative Analysis).
These
recommendations are minimum standards for the forensic identification of
commonly seized drugs. However, it
should be recognized that they may not be sufficient for the identification of
all drugs in all circumstances. Within
these recommendations, it is up to the individual laboratory’s management to
determine which combination of analytical techniques best satisfies the requirements
of its jurisdiction.
METHODS
OF ANALYSIS/CLANDESTINE DRUG LABORATORY EVIDENCE
These recommendations are intended to
be used in conjunction with the general requirements for the analysis of seized
drugs. This document provides guidance
on the chemical analysis of items and samples related to suspected clandestine
drug laboratories. It does not address
scene attendance or scene processing.
This document provides general recommendations for the analysis of
clandestine laboratory evidence and is not a substitute for detailed and
validated laboratory policies and technical procedures.
IIIC.1.1
SWGDRUG
considers an understanding of clandestine laboratory synthetic routes and the
techniques used in the analysis of related samples to be fundamental to the
interpretation and reporting of results.
This understanding assures that results and conclusions from methods are
reliable and analytical schemes are fit for purpose.
IIIC.1.2
The
qualitative and quantitative analyses of clandestine laboratory evidence can
require different approaches relative to routine seized drug analyses. Analysts shall understand the limitations of
the procedures used in their qualitative and quantitative analyses.
IIIC.1.3
Laboratory
management shall ensure that clandestine laboratory synthesis and analysis
training be provided through relevant procedures, literature, and practical
experience. Practical experience
typically includes production, sampling and analysis of clandestine laboratory
training samples.
IIIC.1.4
Laboratory
management shall ensure that chemical safety and hygiene plans address and
mitigate hazards associated with clandestine laboratory evidence.
IIIC.1.5
Laboratory
management shall consider customer / local requirements which influence the
application of these recommendations.
IIIC.2.1
Many
items seized at clandestine laboratories may be intrinsically dangerous. These may include items of unknown
composition and chemicals that have not been fully characterized and whose
specific hazards are not known.
Therefore, caution must be exercised and routine safety protocols may
not be sufficient.
IIIC.2.2
The
following are required in addition to the routine laboratory safety program in
place for the analysis of seized drugs (see Part
IVA – Health and Safety):
·
safety
procedures and in the use of safety and protective equipment for all
staff responsible for handling items
·
protective
breathing equipment
·
listings
of the relevant hazards (e.g. MSDS) associated with components commonly found
at clandestine laboratory sites and knowing what they mean
·
accident
prevention, emergency response procedures, and incident reporting protocols
IIIC.2.3
The
handling, analysis, and storage of items seized from clandestine laboratories
require additional procedures, facilities and equipment. (see Part IVA – Physical Plant): Examples are:
·
specialized ventilation equipment (e.g.
fume hoods) to prevent exposure to harmful fumes and vapors
·
provision of personal protective
equipment such as safety glasses, chemical resistant gloves, laboratory coats,
respirators, face masks, and air monitors
·
maintenance of a clean, uncluttered
workspace
·
specialized emergency equipment
stations
·
chemical disposal and destruction
facilities and procedures
·
specialized evidence receipt, storage
and disposal requirements designed to mitigate expected dangers (e.g. limited
sample size, proper packaging of reactive materials, use of absorbents,
properly ventilated storage)
IIIC.2.4
Analysts
shall be aware of the hazards associated with clandestine laboratories
samples. Examples are:
·
extracting from strong acids and bases
(e.g. hydriodic acid, sodium hydroxide)
·
handling fuming acids and bases (e.g.
hydrochloric acid, ammonia)
·
poisonous gases (e.g. phosphine,
chlorine, hydrogen sulfide) and their potential release from evidence during
analysis
·
poisonous, carcinogenic, and mutagenic
materials (e.g. mercuric chloride, chloroform, potassium cyanide)
·
reactive and air sensitive materials
(e.g. white phosphorus, lithium)
·
potential testing incompatibilities
(e.g. phosphorus with Raman, color test reagents with cyanide salts, exothermic
reactions)
·
radioactive materials (e.g. thorium)
·
volatile and flammable solvents (e.g.
acetone, diethyl ether, methylated spirits)
IIIC.3
Sample
selection for analysis
IIIC.3.1
The
primary purpose of analysis is to prove or disprove allegations of clandestine
drug syntheses. Accordingly, analysts
must select items which relate to the manufacturing process.
IIIC.3.2
Not
all items seized at a clandestine laboratory site may need to be analyzed. It is recommended that information be shared
between the analyst and on-scene personnel to aid in sample selection.
IIIC.3.3
Items
should be selected for analysis, based on jurisdictional requirements, and
which are likely to contain:
·
finished product
·
intermediates
·
precursors
·
key reagents
·
reaction mixtures
IIIC.3.4
Some
of the following types of items may be analyzed as they can assist in
determining the chemical reaction(s) undertaken and the scope of the
clandestine laboratory:
·
materials that appear to be waste
·
unlabeled materials that appear to be
contaminated solvents, acids, or bases
·
samples from contaminated equipment
IIIC.3.5
Items
that are readily obtained from local retail stores and are sold from reputable
manufacturers/distributors may not need to be analyzed, particularly if
collected from sealed and labeled containers.
These include:
·
solvents (e.g. toluene, mineral
spirits)
·
acids (e.g. hydrochloric acid, sulfuric
acid)
·
bases (e.g. sodium hydroxide, ammonia
water)
IIIC.4.1
Substances
whose presence are reported or contribute to formulating reported conclusions
shall be identified with an adequate analytical scheme.
IIIC.4.2
Where
possible, the identification of organic compounds shall follow the guidelines
for the analysis of seized drugs (see Part III B – Drug Identification).
IIIC.4.3
The
discriminating power of analytical techniques for the identification of
inorganic materials depends on the particular analyte. In each case the analytical scheme shall:
·
have sufficient discriminating power to
identify the material to the exclusion of others (e.g. identification of both
the cation and anion in salts)
·
utilize two or more techniques,
preferably from different analytical groups described below
IIIC.4.4
The
following list of analytical groups and techniques are in no particular order
and are not exhaustive. Analytical
techniques must be selected which provide sufficient discriminating power for
each analyte. Some techniques may not be
useful for particular analytes and each must be evaluated to determine
suitability.
IIIC.4.4.1 Analytical Group 1: Elemental Analysis
Techniques – these
techniques may provide positive results for elements present in a sample but
typically require additional tests to distinguish forms (e.g. oxidation state).
·
Atomic Absorption Spectroscopy
·
Atomic Emission Spectroscopy and Flame
Tests (an attached spectrometer significantly increases the discriminating
power relative to flame tests)
·
Energy Dispersive X-Ray Detectors for
Scanning Electron Microscopes (SEM-EDX)
·
Mass Spectrometry (utilizing
Inductively Coupled Plasma sources or for elements with unique isotopic
abundance patterns)
·
X-Ray Fluorescence (XRF)
IIIC.4.4.2 Analytical Group 2: Structural
Elucidation Techniques
– these techniques may have high discriminating power for polyatomic analytes.
·
Infrared Spectroscopy (IR and FTIR)
·
Mass Spectrometry
·
Nuclear Magnetic Resonance (NMR)
·
Raman Spectroscopy
·
UV-Vis & Fluorescence Spectroscopy
IIIC.4.4.3 Analytical Group 3: Separation
Techniques – these
techniques can be valuable for mixtures and for distinguishing different forms
of an element (e.g. phosphate and phosphite).
·
Capillary Electrophoresis
·
Gas Chromatography
·
Ion Chromatography
·
Liquid Chromatography
·
Thin Layer Chromatography
IIIC.4.4.4 Analytical Group 4: Chemical
Properties – These
techniques involve observations of chemical changes. Utilizing several of these techniques, in
series or combination, can often increase discriminating power.
·
Flammability
·
Microcrystalline tests
·
pH (of liquids or vapors)
·
Radioactive decay
·
Reactivity with water, air, or other
materials
·
Solubility and miscibility tests
·
Spot and precipitation tests
IIIC.4.4.5 Analytical Group 5: Physical
Properties – These
techniques involve observations of physical properties. The discriminating power of these techniques
depends on the measuring device.
·
Color
·
Crystal forms measured with polarized
light microscopy or x-ray diffraction techniques
·
Density (relative density and density
of mixtures have reduced discriminating power)
·
Phase transitions including melting
points, boiling points, sublimation temperature and vapor pressure
·
Physical state or states
·
Refractive index
·
Viscosity and surface tension
IIIC.4.5
If
limited or qualified conclusions are sufficient (e.g. basic aqueous layer,
non-polar organic solvent, a material containing the element phosphorus), tests
of limited discriminating power may be utilized within an analytical scheme.
IIIC.4.6
Analytical
reference materials may not be available for the analysis of intermediates and
byproducts. In these cases, samples
taken from a test reaction in conjunction with suitable reference literature
may be used for comparison purposes.
IIIC.4.7
Quantitative
measurements of clandestine laboratory samples have an accuracy which is
dependent on sampling and, if a liquid, on volume calculations. Accordingly, these measurements and
calculations may be based on estimates.
Under these conditions, a rigorous calculation of measurement
uncertainty is often not possible or necessary and the uncertainty may best be
conveyed by using a qualifier statement on the report (e.g. approximately, not
to exceed, no less than).
IIIC.5 Yield and capacity calculations
IIIC.5.1
Yield
and capacity calculations can be achieved from a number of approaches and shall
be based on relevant case information, suitable literature, laboratory and
jurisdictional requirements.
IIIC.5.2
Reported
yields and capacities shall be based upon information documented in the
laboratory case file.
IIIC.5.3
Calculated
yields can be expressed as theoretical or expected.
IIIC.5.3.1 SWGDRUG recommends that reported
yields be accompanied with an explanation clarifying the limitations or
considerations.
IIIC.5.3.1.1
Theoretical
yields are calculated based on the amount of known chemical, the stoichiometry
of the reaction used in the clandestine laboratory and the product. Theoretical yields are not achievable in
practice and their reporting can be misinterpreted.
IIIC.5.3.1.2
Expected
yields are calculated based upon published data, experience, or practical
experimentation. Expected yields can be
highly variable based upon the factors listed below.
IIIC.5.4
In
calculating expected yields and capacities in clandestine laboratories, many
different sources of information can be used.
Each case is different and will have a different set of evidence from
which to draw information, including, but not limited to:
·
amounts of finished products,
precursors, or essential chemicals present
·
amount of waste present
·
size of reaction vessels and equipment
·
volume and quantity of containers
·
type / quantity of equipment and
chemicals used
·
state of equipment and premises (e.g.
cleanliness of site and equipment)
·
the apparent skill and laboratory
practice of the operator
·
the procedures (i.e. recipe) followed
by the operator
IIIC.5.5
In
addition to observations about the clandestine laboratory site itself, other
pieces of evidence can lead to an understanding of yields and capacities,
including, but not limited to:
·
length of time the laboratory has been
in operation
·
intercepted conversations
·
statements made by the clandestine
laboratory operator during an interview/interrogation
·
documents describing purchases of
equipment, precursors, or reagents
·
photographs of the clandestine
laboratory site and other related areas.
· records kept by the clandestine laboratory operator (e.g. seized recipes or records of previously manufactured quantities)
IIIC.5.6
When
calculating capacity, ensure that the values were not obtained from the same
source (e.g. empty blister packs and tablet waste).
IIIC.6
Reports
and conclusions
IIIC.6.1
Communications
and reports, either written or verbal, shall be based upon all of the available
and relevant information and with clearly stated assumptions and conditions.
IIIC.6.2
There
are many facets to a clandestine laboratory investigation, such as:
·
the illicit drug being made
·
the synthetic route being utilized
·
the type of equipment found at the
site
·
the past/potential production at the
site
·
the final form of the illicit drug
·
the batch size at the site
·
whether a tableting
/ encapsulating operation was present
IIIC.6.3
Factors
to consider in determining what to report include, but are not limited to:
·
jurisdictional requirements
·
governing body (agency) requirements
·
customer requests
·
potential exculpatory information
·
samples / analytes which represent the
multiple stages in a reaction process
IIIC.6.4
Laboratories
should have documented policies establishing protocols for reviewing verbal
information and conclusions should be subject to technical review whenever
possible. It is acknowledged that
responding to queries in court or investigative needs may present an
exception.
IIIC.6.5
When
technical reviews are conducted, the individual reviewing the conclusions must
be knowledgeable in the processing, analysis, and reporting of clandestine
laboratory seizures.
IIIC.7.1
Analysis
and interpretation of a clandestine laboratory case requires specialized
skills. The main objective of
clandestine laboratory training programs should be to provide new analysts with
a sound education in the fundamental areas of clandestine laboratory evidence
analysis. These guidelines assume the
student is qualified as a seized drug analyst.
IIIC.7.2
Analysts
shall receive training which will enable them to safely perform the analysis of
clandestine drug laboratory samples.
IIIC.7.3
Analysts
shall receive training which will enable them to assist in investigation of
clandestine drug syntheses. Aspects of
this training may include:
·
chemical separation techniques (e.g.
acid/base extractions, ion pair extractions, precipitation)
·
production estimates
·
study of pertinent drug syntheses by
various routes
·
training on intermediates and route
specific by-products
·
knowledge of common and alternative
sources of chemicals
·
training in inorganic chemistry,
analysis techniques, and interpretation
·
common terminology used in organic
chemistry and synthesis
·
application of critical thinking and
problem solving skills to the evaluation of all case information (e.g. officer
and scene reports, recipes, chemical data)
·
the ability to recognize when
additional information is required, identify sources for that information
(journals, monographs, underground references), critically evaluate the
reference and apply that knowledge to case information
·
legal issues and courtroom testimony
IIIC.7.4
Analysts
should stay current in the field of clandestine drug manufacturing and
clandestine laboratory investigations.
Examples of this element include:
·
joining regional, national, and
international scientific organizations
·
attending conferences specializing in
clandestine drug manufacture
·
receiving training by qualified
instructors covering current trends and reviews
·
reading pertinent scientific literature
·
monitoring relevant illicit literature
and sites
PART
IIID
METHODS
OF ANALYSIS/ANALOGUES AND STRUCTURAL CLASS DETERMINATIONS
IIID.1.1
This
section provides general recommendations regarding analogues and structural
class determinations.
IIID.1.2
Jurisdictional
requirements for such determinations may include structural or pharmacological
(real or purported) similarity to known controlled substances or structural
class definitions.
IIID.1.3
SWGDRUG
considers it fundamental for analysts to fully understand how analogues and
structural classes are legally defined in a particular jurisdiction and the
applicable elements of their local legislative requirements prior to developing
or reporting opinions.
IIID.1.4
Such
opinions should only be rendered by those with proper training and experience,
as defined by laboratory procedures.
IIID.2.1
The
requirements for legal consideration as a controlled substance analogue are
defined in jurisdictional legislation.
IIID.2.2
Classification
as a controlled substance analogue generally involves the evaluation of the
similarity of structure or pharmacological properties of a chemical compound to
a known controlled substance.
IIID.2.3
The
scientific evaluation of similarity may be made using a variety of techniques
and approaches depending on the specific question being addressed. These specific comparisons can be broadly
classified by structure, chemical properties, biochemical or pharmacological
activity.
IIID.2.4
The
laboratory shall have a written procedure regarding structural similarity
determinations, which shall include a description of the factors to be
considered during the comparison and how each shall be documented in the case
file.
IIID.2.5
The
documentation of the evaluation of similarities between chemical compounds
shall include a discussion of how the compounds are similar and how they are
different.
IIID.2.5.1
Evaluation
of similarity is a subjective matter and opinions may differ.
IIID.2.5.2
Structural
comparisons in a forensic laboratory may be limited to the structural class and
functional group, ring or chain substitutions.
As examples, isomers, homologues, salt forms, atomic substitutions,
esters, and ethers may be considered. The scope of comparison conducted should
be made clear in the report.
IIID.2.6
Structural
similarity between two chemical compounds is not an adequate basis to infer
similar pharmacological activity, e.g. naloxone and hydromorphone.
IIID.2.7
Likewise
a lack of structural similarity is not an adequate basis to infer a lack of
analogous pharmacological activity, e.g. fentanyl and morphine.
IIID.2.8
If
pharmacological activity is a requirement of particular legislation and drug
analysts are asked for such information by the judge or presiding authority,
they should not provide such testimony in the absence of specific training and
experience in pharmacology (or related fields).
Should the drug analyst cite peer-reviewed literature, they shall
qualify the limitations of their expertise.
IIID.3 Structural
Class Determinations
IIID.3.1
In
many jurisdictions, chemical compounds are controlled based upon structural
class definitions (e.g., 3-(1-naphthoyl)indole
with substitution at the nitrogen atom of the indole ring, whether or not
further substituted on the indole ring to any extent, whether or not
substituted on the naphthoyl ring to any extent).
IIID.3.2
A
structural class determination may be made by identifying a specific compound
and assigning the compound as a member of a legally defined structural class.
IIID.3.3
The
laboratory shall have a written procedure for structural class determinations,
which should include the documentation requirements for the assignment of the
unknown to a structural class.
IIID.3.4
The
analytical scheme employed must satisfy all structural requirements of the
structural class definition, e.g. where substitutions are, types of
substitutions.
IIID.3.5
A
structural class determination may also be made using an analytical scheme
designed to identify sufficient features of a compound to assign it as a member
of a legally defined structural class without making a conclusive
identification of that compound (e.g., ortho, meta, or para position of a
halogen on an aromatic ring).
IIID.3.6
Relevant
limitations of the analytical scheme and resulting classification shall be
clear in reporting, e.g. The powder was analyzed and found to contain a
chemical in the legally defined chemical class Amphetamine, specifically (2, 3,
or 4)-fluoroamphetamine.
IIID.4.1
All
conclusions and opinions expressed in written or oral form shall be based on
sufficient supporting evidence, data, or information, as defined by laboratory
procedures.
IIID.4.2
The
basis of any conclusion should be completely documented in the case notes and
summarized in the written report and subject to the laboratory’s review
policy. It is acknowledged that
responding to queries in court or investigative needs may present an exception.
IIID.4.3
Conclusions and opinions reported shall be accurate,
clear, and meet the jurisdictional requirements. The report must also include any relevant
assumptions or limitations (e.g. potentially exculpatory information), to allow
the court to make the
final decision.
IIID.4.4
The
report should clearly indicate what elements of the legal requirements were
evaluated and what elements were not evaluated.
IIID.4.5
The
scope of opinions and conclusions reported, in either written or oral form,
shall not go beyond the knowledge, training and experience of the analyst.
PART
IV A
QUALITY
ASSURANCE/GENERAL PRACTICES
It is the goal of a laboratory's drug analysis program to provide the customers
of the laboratory's services access to quality drug analysis. It is the goal of these recommendations in
PART IV A to provide a quality framework for management of the processing of
drug casework, including handling of evidentiary material, management
practices, qualitative and quantitative analysis
and reporting. These are minimum
recommendations for practice.
The term
“evidence” has many meanings throughout the international community. In this document it is used to describe drug
exhibits that enter a laboratory system.
IVA.2 Quality
management system
A documented quality
management system shall be established and maintained.
IVA.2.1 Personnel responsible
for this shall be clearly designated and shall have direct access to the
highest level of management concerning laboratory policy.
IVA.2.2
The
quality management system shall cover all procedures and reports associated
with drug analysis.
The
Job descriptions for all personnel should include responsibilities, duties and
required skills.
IVA.3.2 Designated
personnel and responsibilities
An
individual (however titled) may be responsible for one or more of the following
duties:
IVA.3.2.1
Quality Assurance Manager: A designated person who is
responsible for maintaining the quality management system (including an annual
review of the program) and who monitors compliance with the program.
IVA.3.2.2
Health & Safety Manager: A designated person who is
responsible for maintaining the Laboratory Health and Safety program (including
an annual review of the program) and monitors compliance with the program.
IVA.3.2.3
Technical Support Personnel: Individuals who perform basic
laboratory duties, but do not analyze evidence.
IVA.3.2.4
Technician/Assistant Analyst: A person who analyzes
evidence, but does not issue reports for court purposes.
IVA.3.2.5
Analyst: A designated person who:
a) examines and analyzes seized drugs or
related materials, or directs such examinations to be done
b) independently
has access to unsealed evidence in order to remove samples from the evidentiary
material for examination AND
c) as
a consequence of such examinations, signs reports for court or other purposes.
IVA.3.2.6
Supervisor: A designated person who has the overall
responsibility and authority for the technical operations of the drug analysis
section. Technical operations include,
but are not limited to protocols, analytical methodology, and technical review
of reports.
IVA.3.3 Qualifications/Education
IVA.3.3.1
Technical
Support Personnel shall
a) have
education, skills and abilities commensurate with their responsibilities AND
b) have
on-the-job training specific to their position.
IVA.3.3.2
Technicians/Assistant
Analysts shall
a) have
education, skills and abilities commensurate with their responsibilities AND
b) have
on-the-job training specific to their position.
IVA.3.3.3 Analysts shall meet educational
requirements stated in PART
II – Education and Training (Section 2).
IVA.3.3.4
Supervisors
shall
a) meet
all the requirements of an analyst (3.3.3),
b) have
a minimum of two (2) years of experience as an analyst in the forensic analysis
of drugs and
c) demonstrate
knowledge necessary to evaluate analytical results and conclusions.
IVA.3.4 Initial
training requirements
Initial training requirements for
analysts are defined in PART II – Education and Training
(Section 4).
IVA.3.5
Maintaining
competence
Continuing
professional development for analysts is defined in PART
II – Education and Training (Section 3).
IVA.4.1
Laboratories
shall provide a healthy, safe and secure environment for its personnel and
operations.
IVA.4.2
Laboratories
shall contain adequate space to perform required analytical functions and
prevent contamination.
IVA.4.3
Chemical
fume hoods shall be provided. They shall
be properly maintained and monitored according to an established schedule.
IVA.4.4
A
laboratory cleaning schedule should be established and implemented.
IVA.4.5
Adequate
facilities shall be provided to ensure the proper safekeeping of evidence,
standards and records.
IVA.4.6
Appropriately
secured storage shall be provided to prevent contamination of chemicals and
reagents.
Laboratories
shall have and follow a documented evidence control system to ensure the
integrity of physical evidence.
IVA.5.1 Receiving
and identifying evidence
Laboratories shall maintain records of
requests for analysis and of the respective items of evidence. For
chain-of-custody purposes, the evidence shall be compared to the submission
documentation, any significant observations of irregularity shall be documented
in the case file or record, and the submitter informed promptly. This file or record shall include, at least,
the following:
·
submission
documents or copies
·
identity
of party requesting analysis and the date of request
·
description
of items of evidence submitted for analysis
·
identity
of the person who delivers the evidence, along with date of submission
·
for
evidence not delivered in person, descriptive information regarding mode of
delivery and tracking information
·
chain
of custody record
·
unique
case identifier.
Evidence shall be properly secured
(e.g., sealed). Appropriate storage
conditions shall ensure that, insofar as possible, the composition of the
seized material is not altered. All
items shall be safeguarded against loss or contamination. Any alteration of the evidence (e.g.
repackaging) shall be documented.
Procedures shall be implemented to assure that samples are and remain
properly labeled throughout the analytical process.
Access to the evidence storage area
shall be granted only to persons with authorization and access shall be
controlled. A system shall be
established to document a chain of custody for evidence in the laboratory.
IVA.5.4 Disposition
of evidence
Records shall be kept regarding the
disposition (e.g., return, destruction, conversion to another use) of all items
of evidence.
IVA.5.5 Documentation
retention procedures
All laboratory records such as
analytical results, measurements, notes, calibrations, chromatograms, spectra
and reports shall be retained in a secure fashion in accordance with
jurisdictional requirements.
IVA.6.1 Analytical
procedures for drug analysis
IVA.6.1.1
Laboratories
shall have and follow documented analytical procedures.
IVA.6.1.2
Laboratories
shall have in place protocols for the sampling of evidence (see PART
III A – Sampling).
IVA.6.1.3
Work
practices shall be established to prevent contamination of evidence during
analysis.
IVA.6.1.4
Laboratories
shall have and follow documented guidelines for the acceptance and
interpretation of data.
IVA.6.1.5
Laboratories
shall monitor the analytical processes using appropriate blanks, controls and reference materials.
IVA.6.1.6
Reference materials and reference data are critical to
demonstrating the validity of quantitative and qualitative test results. A positive test result shall meet the
acceptance criteria defined in the method validation and operating
protocol. In descending order of
preference SWGDRUG recommends that the acceptance criteria should be based on:
IVA.6.1.6.1 Comparison to data obtained from a
suitable drug reference material analyzed under the same analytical conditions
as the test/case sample.
The
reference material may be analyzed:
·
contemporaneously
with test/case sample
·
as
part of routine quality control e.g.
daily check solutions
·
at
a previous date (e.g. method validation, in-house library)
IVA.6.1.6.2 Comparisons to external reference data
may be used where a reference material is unavailable. External reference data shall be shown to be
fit for purpose. The veracity of the data shall be considered and
assessed. Factors to consider include
·
Origin
of the data
·
Validation
of the data
·
Peer
review of the data
·
Comparability
of analytical conditions
The
use of external reference data rather than a reference material should be
documented and where applicable the limitation expressed within the
report.
IVA.6.1.6.3 When neither reference materials nor
external reference data are available, structural elucidation techniques may be
employed providing the analyst has the appropriate skills for their
interpretation. Such interpretations shall be made only by analysts competent
in structural elucidation interpretation. The absence of a reference material
and external data shall be documented and the impact on the interpretation of
reported results assessed.
IVA.6.1.7
Analytical
procedures shall be validated in compliance with PART IV B - Validation.
IVA.6.1.8
When
analysts determine the identity of a drug in a sample, they shall employ
quality assurance measures to ensure the results correspond to the
exhibit. (see Part III B – Drug
Identification)
IVA.6.2 Assessment
of drug reference materials
ISO/IEC 17025 specifies that
reference materials shall, where possible, be traceable to SI units of
measurement, or to certified reference materials (CRM). For seized drugs this
requirement is difficult to fulfil because the concept of traceability for drug
standards is not internationally established and CRM’s for drug analysis are
not readily available or affordable.
Note: A
certificate does not necessarily define a material as a CRM.
IVA.6.2.1
SWGDRUG recommends laboratories have a process for assessing
that reference materials are fit for purpose.
IVA.6.2.1.1 The assessment and purpose of a reference material shall be documented.
The documentation shall include the name of the individual who performed the
assessment, the date of assessment, verification test data, and details of all
reference materials and reference data used.
IVA.6.2.2
To be fit for purpose, the reference material must
meet the minimum specification defined in the validation (see Part IV B - Reference Materials).
IVA.6.2.2.1 The
assessment shall be done on each lot of reference material.
IVA.6.2.2.2 This
assessment shall be completed prior to or alongside casework analysis as
appropriate.
IVA.6.2.2.3
Reference materials shall only be used for
the purpose defined by the laboratory. For example a reference material may be
deemed suitable for qualitative but not quantitative determinations.
IVA.6.2.3
Fit for purpose for qualitative work requires an
assessment of chemical identity.
IVA.6.2.4
Fit for purpose for quantitative work requires an assessment
of purity and/or concentration, as appropriate to the
application and its associated uncertainty of measurement in addition to
the parameters in 6.2.3.
IVA.6.2.4.1
For quantitative determinations, different
sources of reference material should be used for calibration and quality
control. Where this is not feasible, two different lots of the same source may
be used or lastly a single source of reference material can be sub-divided and
each part assigned a specific purpose.
IVA.6.2.5
These parameters in Sections 6.2.3 and 6.2.4 may be
described in a certificate, statement of analysis, data sheet or label supplied
with the material or may be determined by in-house analysis or reference to
published literature.
IVA.6.2.6
The laboratory shall assess the reliability of the
information supplied with a reference material even if the material meets the
definition of a CRM.
IVA.6.2.6.1 For
reference materials obtained from a provider accredited under ISO Guide 34, the
information contained in the accompanying certificate is considered reliable and
can be accepted as correct if the material is stored and
used in accordance with the manufacturer’s instructions. In these
circumstances the assessment need not include analysis.
IVA.6.2.6.1.1
For reference materials obtained from a provider not
accredited under ISO Guide 34 the identity and purity information supplied by
the provider shall be verified by analysis. When
verification by analysis is not possible, this shall be documented and where
applicable the limitation expressed within the report. Other information may be evaluated as needed.
IVA.6.2.6.1.2
Examples of verification of chemical identity by
analysis:
·
Analysis and comparison of the results to
peer-reviewed published data, data produced by a laboratory accredited under
ISO/IEC 17025, or to data produced from a previously verified reference
material.
·
Evaluation of data from in-house structural elucidation
analysis of the material.
IVA.6.2.6.1.3
Examples of verification of purity by analysis
utilizing validated methods:
·
Quantitative NMR Spectroscopy
·
Quantitative UV- Visible Spectroscopy
·
Comparison to previously verified material
IVA.6.2.6.2
Where a reference material has no or limited
supporting documentation or is produced in-house (by synthesis or from a case
sample), then the chemical identity shall be determined in sufficient detail to
demonstrate that it is fit for purpose. In addition, for quantitative work the
purity and associated uncertainty of measurement shall also be determined.
IVA.6.2.7 Reference
materials should have an expiration date.
IVA.6.2.7.1
If the material is not supplied with an expiration date, one should be assigned at the first
assessment (section 6.2.3, 6.2.4). If the expiration
date passes before the material is fully used, then the material can be
re-assessed and the expiration date extended. The laboratory protocol for extending expiration dates shall be documented and should
include analysis of the material.
IVA.6.2.7.2
If expiration dates are
not assigned to reference materials, the laboratory must have a documented
protocol for assessing the validity of the reference material each time it is
used.
IVA.7 Instrument/Equipment
performance
IVA.7.1 Instrument
performance
Instruments shall be routinely
monitored to ensure that proper performance is maintained.
IVA.7.1.1
Monitoring
shall include, at least,
the use of blanks and reference materials, test
mixtures, or calibration standards.
IVA.7.1.2
Instrument
performance monitoring shall be documented.
IVA.7.1.3
The
manufacturer's operation manual and other relevant documentation for
instrumentation should be readily available.
IVA.7.2.1
Only
suitable and properly operating equipment shall be employed.
IVA.7.2.2
Equipment
performance parameters should be routinely monitored and documented.
IVA.7.2.3
The
manufacturer's operation manual and other relevant documentation for each piece
of equipment should be readily available.
IVA.8.1
Chemicals
and reagents used in drug testing shall be of appropriate grade for the tests
performed.
IVA.8.2
There
shall be documented formulations for all chemical reagents produced within the
laboratory.
IVA.8.3
Documentation
for reagents prepared within the laboratory shall include identity,
concentration (when appropriate), date of preparation, identity of the
individual preparing the reagents, storage conditions (if appropriate) and the
expiration date (if appropriate).
IVA.8.4
The
efficacy of all test reagents shall be checked prior to their use in casework.
Results of these tests shall be documented.
IVA.8.5
Chemical
and reagent containers shall be dated and
initialed when received and also when first opened.
IVA.8.6
Chemical
and reagent containers shall be labeled as to their contents.
IVA.9 Casework
documentation, report writing and review
IVA.9.1 Casework
documentation
IVA.9.1.1
Documentation
shall contain sufficient information to allow a peer to evaluate case notes and
interpret the data.
IVA.9.1.2
Evidence
handling documentation shall include chain of custody, information regarding
packaging of the evidence upon receipt, the initial weight/count of evidence to
be examined (upon opening), a description of the evidence and communications
regarding the case.
IVA.9.1.3
Analytical
documentation should include procedures, standards, blanks, observations, test
results and supporting documentation including charts, graphs and spectra
generated during an analysis.
IVA.9.1.4
Casework
documentation shall be preserved according to documented laboratory policy.
Reports issued by laboratories shall be accurate,
clear, objective, and meet the requirements of the jurisdictions served.
These reports shall include the following
information:
• title
of report
• identity
and location of the testing laboratory
• unique
case identifier (on each page)
• clear
identification of the end of the report (e.g., Page 3 of 3)
• submitting
agency
• date
of receipt of evidence
• date
of report
• descriptive
list of submitted evidence
• identity
and signature (or electronic equivalent) of analyst
• results
/ conclusions
• a
list of analytical techniques employed
• sampling (see Part III A - Reporting)
• uncertainty
(see Part IV C - Uncertainty).
If elements listed above are not included on the
report, the laboratory shall have documented reasons (i.e. specific
accreditation, customer or jurisdictional considerations), for not doing so.
9.1.1
Laboratories
shall have documented policies establishing protocols for technical and
administrative case review.
9.1.2
Laboratories
shall have a documented policy for resolving case review disagreements between
analysts and reviewers.
IVA.10Proficiency
and competency testing
Each
laboratory shall establish a documented competency testing and proficiency
testing program. Each laboratory shall
have documented protocols for monitoring the competency and proficiency of its
analysts.
NOTE It is recognized that different jurisdictions
may define competency and proficiency testing in a manner other than how they
are used here. In this context,
competency tests measure the ability of the analyst to produce accurate
results. Proficiency tests are an
ongoing process in which a series of proficiency samples, the characteristics
of which are not known to the participants, are sent to laboratories on a
regular basis. Each laboratory is tested
for its accuracy in identifying the presence (or concentration) of the drug
using its usual procedures.
IVA.10.1.1
Laboratories
shall perform proficiency testing in order to verify the laboratory's
performance. The frequency of the
proficiency testing shall be, at least, annually. Where possible, at least one of these
proficiency tests should be from a recognized external proficiency test
provider.
IVA.10.1.2
Proficiency
test samples should be representative of the laboratory's normal casework.
IVA.10.1.3
The
analytical scheme applied to the proficiency test should be in concert with
normal laboratory analysis procedures.
IVA.10.2.1
Laboratories
shall monitor the competency of their analysts annually.
IVA.10.2.2
If
competency test samples are utilized, they should be representative of the
laboratory's normal casework.
IVA.10.2.3
The
analytical scheme applied to the competency test should be in concert with
normal laboratory analysis procedures.
IVA.11Analytical
method validation and verification
IVA.11.1
Method
validation is required to demonstrate that methods are suitable for their
intended purpose (see PART IV B – Validation).
IVA.12.1 Internal audits of laboratory operations shall be conducted at least once a year.
IVA.12.2 Records of each audit shall be
maintained and include the scope, date of the
audit, name of auditor(s), findings and any necessary corrective actions.
In the course of examining seized drug
samples and related materials, laboratories may encounter some operations or
results that are deficient in some manner.
Each laboratory shall have a documented policy to address such
deficiencies.
IVA.13.1
This
policy shall include the following:
a) a
definition of a deficiency as any erroneous analytical result or
interpretation, or any unapproved deviation from an established policy or
procedure in an analysis;
NOTE Deviations from
established policy shall have documented management approval.
b) a
requirement for immediate cessation of the activity or work of the individual
involved, if warranted by the seriousness of the deficiency, as defined in the
documented policy;
c) a
requirement for administrative review of the activity or work of the individual
involved;
d) a
requirement for evaluation of the impact the deficiency might have had on other operations,
equipment, materials, or laboratory personnel;
e) a
requirement for documentation of the follow-up action taken as a result of the
review;
f) a
requirement for communication to appropriate employees of any confirmed
deficiency which may have implications for their work.
NOTE It should be
recognized that to be effective, the definition for "deficiency of
analysis" shall be relatively broad.
As such, deficiencies may have markedly different degrees of
seriousness. For example, a
misidentification of a controlled substance would be very serious and perhaps
require that either the methodology or the analyst be suspended pending
appropriate remedial action, as determined by management. However, other deficiencies might be more
clerical in nature, requiring a simple correction at the first line supervisory
level, without any suspension of methodology or personnel. Thus, it may well be advantageous to identify
the differing levels of seriousness for deficiencies and make the action
required be commensurate with the seriousness.
Laboratories
shall have a documented health and safety program in place.
IVA.14.1 Health
and safety requirements
IVA.14.1.1
All
personnel should receive appropriate health and safety training.
IVA.14.1.2
Laboratories
shall operate in accordance with laboratory policy and comply with any relevant
regulations.
IVA.14.1.3
Laboratory
health and safety manual(s) shall be readily available to all laboratory
personnel.
IVA.14.1.4
Safety Data
Sheets shall be readily available to all laboratory personnel.
IVA.14.1.5 All chemicals, biohazards and supplies
shall be stored and disposed of according to applicable government regulations
and laboratory policy.
IVA.14.1.6 Safety hazards such as syringes, items
with sharp edges or noxious substances should be so labeled.
IVA.15Additional
documentation
In
addition to casework documentation, laboratories shall maintain documentation
on the following topics:
·
test
methods/procedures for drug analysis
·
reference
materials (including source and verification)
·
preparation
and testing of reagents
·
evidence
handling protocols
·
instrument
and equipment calibration and maintenance
·
instrument
and equipment inventory (e.g., manufacturer, model, serial number, acquisition
date)
·
proficiency
testing
·
personnel
training and qualifications
·
quality
assurance protocols and audits
·
health,
safety and security protocols
·
validation
data and results
·
uncertainty
data.
PART IV B
QUALITY ASSURANCE/VALIDATION OF ANALYTICAL
METHODS
IVB.1.1 Definition
and purpose of validation
Validation is the confirmation by examination and
the provision of objective evidence that the particular requirements for a
specific intended use are fulfilled.
There are numerous documents that address the topic of validation but
there are few validation protocols for methods specific to seized drug
analysis.
An
analytical scheme shall be comprised of validated methods that are appropriate
for the analyte.
IVB.1.2.1 The
combinations of methods chosen for a particular analytical scheme shall
identify the specific drug of interest, preclude a false positive and minimize
false negatives.
IVB.1.2.2 For
quantification the method should reliably determine the amount of analyte
present.
IVB.1.2.3
If
validated methods are used from published literature or another laboratory’s
protocols, then the methods shall be verified within each laboratory.
IVB.1.2.4 If
non-routine validated methods are used, then the method shall be verified prior
to use.
IVB.1.2.5 Verification
should, at a minimum, demonstrate that a representative set of reference
materials has been carried through the process and yielded the expected
results.
IVB.1.3 Individual
laboratory responsibility
Each laboratory should determine whether their
current standard operating procedures have been validated, verified or require
further validation/verification.
IVB.1.4 Operational
environment
All methods shall be validated or
verified to demonstrate that they will perform in the normal operational
environment when used by individuals expected to utilize the methods on
casework.
The entire validation/verification process shall be
documented and the documentation shall be retained. Documentation shall include, but is not limited
to the following:
·
personnel involved
·
dates
·
observations from the process
·
analytical data
·
a statement of conclusions and/or recommendations
·
authorization approval signature.
To meet the above requirements, SWGDRUG recommends
that laboratories follow the applicable provisions of Section 2 [General
Validation Plan] when validating seized drug analytical methods.
For further information, see Supplemental Document SD-2
(Preparing Validation Plans, Section I: Analytical Techniques – Elements to
Consider and Section II: Example Validation Plan for GC/MS Identification and
Quantitation of Heroin).
This is an introductory statement that
will specify what is being tested, the purpose of the testing and the result(s)
required for acceptance.
IVB.2.1.1 Performance
specification
A list of specific objectives (e.g.,
trueness and precision) should be determined prior to the validation process.
After completion of the validation
process the objectives should be revisited to ensure that they have been
satisfactorily met.
State exactly the method to be
validated. It is essential that each
step in the method be demonstrated to perform satisfactorily. Steps that constitute a method for the
identification and/or quantification of seized drugs may include:
·
visual characterization (e.g., macroscopic
examination)
·
determination of quantity of sample, which may
include:
o
weight
o
volume
o
item count
·
sampling (representative or random, dry,
homogenized, etc.)
·
stability of analyte
·
sample preparation
o
extraction method
o
dissolution
o
derivatization
o
crystallization
o
techniques for introducing sample into
instrumentation
o
list the instruments and equipment (e.g., balance
and glassware) utilized
o
instrument conditions
·
software applications (e.g., software
version, macros)
·
calculations
o
equation(s) to be used
o
unit specification
o
number of measurements required
o
reference values
o
significant figure conventions
o
conditions for data rejection
o
uncertainty determination.
Appropriate
reference materials (see Part
IV A – Assessment of Reference Materials) shall be used to develop and validate analytical
procedures. The validation documentation
and operating protocol should define the frequency of usage of the relevant
reference materials and their minimum specification (e.g. salt form, minimum
purity, isomeric form).
IVB.2.4
Performance
characteristics
Assess the capability of the method to
identify/quantify the analyte(s) of interest, whether pure or in a mixture.
Assess the
impact of any interfering components and demonstrate that the method works in
the presence of substances that are commonly encountered in seized drug samples
(e.g. cutting agents, impurities, by-products, precursors).
May
be determined for quantitative analysis.
IVB.2.4.4.1
Precision
(Repeatability/Reproducibility)
Determine
the repeatability and reproducibility of all routine methods. Conditions under which these determinations
are made shall be specified.
NOTE Reproducibility
determination may be limited to studies within the same laboratory.
IVB.2.4.4.1.1
Within
the scope of the validation, determine acceptable limits for repeatability and
reproducibility.
IVB.2.4.4.1.2
For
qualitative analysis, run the qualitative method a minimum of ten times.
IVB.2.4.4.1.3
For
quantitative analysis run the quantitative method a minimum of ten times.
IVB.2.4.4.1.4
Validation
criteria for non-routine methods may differ from what is stated above.
Trueness shall be determined for
quantitative methods to assess systematic error. Trueness can be assessed through various
methods such as:
·
comparison of a method-generated value for the
reference material with its known value using replicate measurements at
different concentrations
·
performance of a standard addition method
·
comparison to proficiency test results
·
comparison with a different validated analytical
method.
Determine
the concentration or sample amount limits for which the method is applicable.
IVB.2.4.5.1
Limit
of detection (LOD)
Limit of detection shall be determined
for all qualitative methods.
IVB.2.4.5.1.1
Determine the lowest amount of analyte that will be
detected and can be identified.
IVB.2.4.5.1.2
The results obtained at the LOD are not necessarily
quantitatively accurate.
IVB.2.4.5.2
Limit
of quantitation (LOQ)
Limit of Quantitation shall be
determined for all quantitative methods.
Determine the lowest concentration that has an acceptable level of
uncertainty.
Linearity
shall be determined for all quantitative methods.
IVB.2.4.5.3.1 Determine
the mathematical relationship (calibration curve) that exists between
concentration and response over a selected range of concentrations.
IVB.2.4.5.3.2 The LOQ
effectively forms the lower end of the working range.
IVB.2.4.5.3.3
Determine
the level of acceptable variation from the calibration curve at various
concentrations.
IVB.2.4.5.3.4 Determine
the upper limits of the working range.
Robustness shall be determined for
either qualitative or quantitative methods.
Alter method parameters individually and determine any changes to
accuracy.
Ruggedness may be determined for either qualitative
or quantitative methods. Ruggedness
should assess the factors external to the method.
The contribution of random and systematic errors to
method result uncertainty shall be assessed and the expanded uncertainty
derived for quantitative methods (see PART IV C –
Uncertainty).
Acceptance criteria for quality
control parameters should be adopted prior to implementation of the method.
a)
The Fitness for Purpose of
Analytical Methods, A Laboratory Guide to Method Validation and Related Topics, EURACHEM
Guide, 1998.
b)
Federal
Register, Part VIII, Department of Health and Human Services, March
1995, pages 11259-62.
c) “Validating
Analytical Chemistry Methods”, Enigma Analytical Training Course (Version
2000-1), Breckenridge, CO, 2000, pages 8-4, 8-5.
d) “Guidelines
for Forensic Science Laboratories”, ILAC-G19:2002, page 10.
PART IV C
This
recommendation provides guidance on the concept of uncertainty and its
application to the qualitative and quantitative analysis of seized drugs. In this context, uncertainty encompasses
limitations of qualitative methods as well as numerical ranges as applied to
quantitative analyses.
IVC.1.1
SWGDRUG
considers an understanding of uncertainty to be fundamental to the
interpretation and reporting of results.
IVC.1.2
The
term “uncertainty” does not imply doubt; rather, its consideration provides
assurance that results and conclusions from methods and analytical schemes are
fit for purpose.
IVC.1.3
SWGDRUG
recommends the concept of uncertainty be considered for all analytical
results.
IVC.1.4
Laboratory
management shall ensure that uncertainty be addressed through the provision of
training, procedures and documentation.
IVC.1.5
Laboratory
management should consider customer requirements which influence the
application of uncertainty.
IVC.1.6
Benefits
The
benefits of determining and understanding uncertainty include:
·
Enhancing
confidence through increased understanding of results
·
Providing
a mechanism to express the reliability of results
·
Enabling
the laboratory and customer to evaluate the fitness for purpose of results
·
Facilitating
the identification of procedural limitations and providing a basis for
improvement
·
Complying
with accreditation requirements.
IVC.1.7
Application of uncertainty
Qualitative and quantitative analyses
require different approaches. Analysts shall understand the limitations of
qualitative and quantitative determinations and have tools to estimate a value
for measurement uncertainty of relevant, but not necessarily all, numerical
results. In this regard, efforts should
be made to use the vocabulary, symbols, and formatting expressed in documents
published by a Standards Developing Organization (SDO) such as ISO and ASTM International.
The
identification of seized drugs requires the combination of methods to form an
analytical scheme (see PART III B - Drug Identification).
IVC.2.1
Individual
methods have limitations and, consequently, uncertainty. Uncertainty of qualitative methods is not
typically expressed in numerical terms.
IVC.2.2
Understanding
these limitations enables the laboratory or analyst to build an appropriate
analytical scheme to correctly identify a drug or chemical.
IVC.2.2.1
It
is expected that, in the absence of unforeseen circumstances, an appropriate
analytical scheme effectively results in no uncertainty in reported
identifications.
IVC.2.2.2
Relevant
limitations of an analytical scheme (e.g., inability to differentiate isomers,
unavailability of reference material) should be documented and may need to be
included in the report (see Part IV C - Reporting Examples).
IVC.3 Quantitative
Measurements
IVC.3.1
Quantitative
measurements have an associated uncertainty, which is defined as a parameter
that “characterizes the dispersion of the values that could
reasonably be attributed to the particular quantity subject to measurement
or characteristic subject to test”
(see Glossary).
IVC.3.2
A
rigorous calculation of measurement uncertainty is not always required.
IVC.3.2.1
A
laboratory shall understand the contributing factors of measurement uncertainty
for each analytical procedure and evaluate them with respect to customer,
accreditation or jurisdictional requirements.
IVC.3.2.2
Where
a value is critical, such as a weight or purity level close to a statutory
threshold, an appropriate measurement uncertainty estimation shall be
applied.
IVC.3.3
Primary
numerical values reported in the analysis of seized drugs are weight and
purity. Where other values are measured
(e.g., size, volume, estimated tablet numbers), the same principles stated
herein apply.
IVC.4 Estimation
of measurement uncertainty for quantitative determinations
IVC.4.1 Sources
of uncertainty for weight determination
IVC.4.1.1
The
uncertainty of a reported value is dependant on the
weighing process. Factors for
consideration include:
·
Single
versus multiple items (number of weighing operations)
·
Taring
of a weighing vessel as a separate weighing operation
·
Extrapolation
of population weight from limited sampling of multiple items
·
Aggregate
weighings
·
Incomplete
recovery of material from the packaging
·
Balance
selection (e.g., readability, capacity, calibration uncertainty)
·
Balance
operation (e.g., sample placement on pan, environmental conditions).
IVC.4.1.2
For
further information and examples of estimation of measurement uncertainty for
weight determinations, see Supplemental Document SD-3 (Measurement Uncertainty for Weight
Determinations in Seized Drug Analysis).
IVC.4.2 Sources
of uncertainty for purity determination
The
uncertainty of a reported purity value is dependant
upon the entire quantitation process.
Factors for consideration include:
·
Sampling
plan (e.g., handling of multiple exhibits)
o Sample homogeneity
·
Analytical
method
o Sample preparation (e.g., sample size,
matrix effects, solubility)
o Analytical technique
o Reference material (e.g., purity of
standard)
o Equipment and instrument properties
(e.g., glassware, pipettors,
balances, chromatographs)
o Concentration of analyte
o Environmental conditions.
IVC.4.3 Factors
relevant to estimation of measurement uncertainty
IVC.4.3.1
When
estimating measurement uncertainty, the following sources of error shall be
considered:
IVC.4.3.1.1 Analytical Error: Systematic and random error both contribute
to measurement uncertainty and shall be addressed through method validation and
quality assurance practices (Part IV B).
SWGDRUG recommends that for all validated procedures, systematic error
is characterized and minimized.
IVC.4.3.1.2 Sampling Error: The sample and sampling procedure are often
the greatest contributors to measurement uncertainty.
IVC.4.3.2
Where
appropriate, confidence levels (e.g., 95% or 99.7%) shall be selected based on
considerations relevant to the analytical context.
IVC.4.3.3
Uncertainty
information shall be recorded in validation documents and/or case records.
IVC.4.4 Approaches for estimating measurement
uncertainty
IVC.4.4.1
Uncertainty
budget approach
IVC.4.4.1.1 In
this approach all sources of error are separately identified and
tabulated.
IVC.4.4.1.2 A
value is assigned to each source of error (collectively or individually) using
either:
·
empirical data (e.g., from validation
process, historical performance data, control chart data, proficiency tests)
·
published data (e.g., volumetric
glassware tolerances)
·
combination of empirical and published
data.
NOTE:
Control chart data, including measurement quality assurance, should be derived
from multiple data points over time and is expected to capture the typical
variations of realistic laboratory processes.
IVC.4.4.1.3 Where
a source has an uncertainty which is insignificant compared to other sources,
it can be excluded.
IVC.4.4.1.4 The
remaining significant values are used to calculate the combined standard
uncertainty and expanded uncertainty.
IVC.4.4.2
Non-budget
approaches
IVC.4.4.2.1 The
sources of uncertainty that are separately assessed in the budget method are
collectively assessed by experimental measurement. In this approach data obtained from a statistically
significant number of replicate analyses utilizing a validated method with an
appropriate sampling plan may be utilized to calculate the
standard or expanded uncertainty.
IVC.4.4.2.2 An
alternate approach involves the use of two standard deviations (2s) of the test method results from
reproducibility data from the validation studies. This provides an approximation of the
measurement uncertainty for non-critical values.
IVC.5
Reporting
of uncertainty
Uncertainty shall be reported when it
may impact the use of a result by the customer, unless the laboratory has
documented reasons (i.e. specific accreditation, customer or jurisdictional
considerations), for not doing so.
Factors which influence the decision to report uncertainty include:
IVC.5.1.1
Jurisdictional
·
Prevailing statutory requirement
·
Relevant governing body (agency)
requirements
·
Customer requests
·
Potential exculpatory value
IVC.5.1.2
Types
of Analysis
·
Qualitative: Qualitative results where limitations of
analytical scheme are known and relevant (e.g., inability to differentiate isomers, unavailability of
reference material)
·
Quantitative: Quantitative measurements where a value is critical
(e.g., weight or purity
level close to a statutory threshold)
IVC.5.1.3
Laboratory
accreditation requirements
Reporting requirements and styles
differ among agencies. The examples
listed below are drawn from laboratories with varied requirements.
IVC.5.2.1
Qualitative
Results
IVC.5.2.1.1 Contains
ephedrine or pseudoephedrine. Item
tested: 5.2 grams net.
IVC.5.2.1.2 Visual examination determined that the
physical characteristics are consistent with a Schedule IV pharmaceutical
preparation containing Diazepam. There
was no apparent tampering of the dosage units and no further tests are being
conducted.
IVC.5.2.1.3 Contains cocaine (salt form not
determined)
IVC.5.2.2
Quantitative
Results
Factors to be considered when reporting
measurement uncertainty include use of significant figures, confidence
intervals and rounding/truncating of results.
IVC.5.2.2.1 Active
drug ingredient (established or common name) methamphetamine hydrochloride
Gross
weight: 25.6 grams
Net
weight: 5.2 grams
Conc.
or purity: 54.7% (±
2.8%)*
Amount
of actual drug: 2.8 grams
Reserve
weight: 5.1 grams
* This value represents the
quantitative uncertainty measurement estimate for the laboratory system.
IVC.5.2.2.2 Positive
for cocaine in the sample tested
Net
weight of total sample: 5.23 grams ±
0.03 grams
Quantitation:
54.7% ±
2.8%
IVC.5.2.2.3 Sample
tested positive for cocaine
Net
weight: 5.23 grams
Purity:
54.7%
Confidence
Range: ±
2.8%*
Calculated
net weight of drug: 2.8 grams of cocaine
*Confidence
range refers to a 95% confidence level.
IVC.5.2.2.4 Cocaine
was identified in the Item 1 powder at a purity of 65 ± 9% (99.7% confidence level). The Item 1 powder weighed 800 ± 4 mg (99.7% confidence level).
IVC.5.2.2.5 White
powder: 5.6 grams
The
range of heroin concentration identified in the sample was not less than 53.2%
and not more than 56.2%.
IVC.6.1
Individuals responsible for
determining, evaluating and documenting uncertainty in the context of
seized-drug analysis shall be capable of competently demonstrating familiarity
with foundational concepts and principles of estimating uncertainty.
IVC.6.1.1
Useful topics to review include:
·
General metrology to include:
terminology, symbols, formulae, publications, international organizations, and
global application as related to seized-drug analysis
·
The concepts of random and systematic
error, accuracy, precision (repeatability, reproducibility, and their
conditions), statistical control, standard and expanded uncertainty, correlation
and propagation of error
·
Reporting conventions including use of
significant figures, truncation and rounding
·
Basic statistics (descriptive and
inferential) to include: measures of central tendency (e.g., median), measures
of variation, statistical modeling, sampling, probability, confidence interval,
and significance level
IVC.6.2
All analysts shall be capable of
explaining their laboratory’s procedures for evaluating uncertainty of
qualitative and quantitative analyses.
IVC.7.1
Eurachem/CITAC
Guide: The Expression of Uncertainty in
Qualitative Testing, Committee Draft September 2003.
IVC.7.2
GUM,
Evaluation of measurement data — Guide
to the expression of uncertainty in measurement Published by the Joint
Committee for Guides in Metrology (JCGM), JCGM 100:2008.
IVC.7.3
Guidelines for Evaluation and Expressing the Uncertainty of NIST
Measurement Results, National Institute of Standards and
Technology, NIST Technical Note 1297, 1994 Edition.
IVC.7.4
General requirements for the competence of testing and calibration
laboratories
International
Organization for Standardization, ISO/IEC 17025: 2005.
IVC.7.5
Guide for the use
of the International System of Units (SI), Taylor, B.N.,
National Institute of Standards and Technology, April 1995.
IVC.7.6
Standard
Practice of Using Significant Digits in Test Data to Determine Conformance with
Specifications, ASTM E29, West Conshohosken, PA.
IVC.7.7
Quantifying
Uncertainty in Analytical Measurements, Eurachem, 2000, 2nd
ED.
IVC.7.8
Experimental
Statistics, M. Natrella, National Bureau of Standards (NBS), USA 1966.
IVC.7.9
ISO 3534-1
Statistics — Vocabulary and symbols Part
1: General statistical terms and terms used in probability, ISO 3534-2 Statistics — Vocabulary and symbols Part 2:
Applied statistics International
Organization for Standardization, Switzerland, 2006.
IVC.7.10
ISO Guide 99:2007
The International Vocabulary of Basic and
General Terms in Metrology, International Organization for Standardization,
Switzerland, 2007.
IVC.7.11
ISO 5725-1
Accuracy (Trueness and Precision) of
Measurement Methods and Results Part 1: General Principles and Definitions International Organization for
Standardization, Switzerland,1994.
IVC.7.12
The Uncertainty of Measurements.
Physical and Chemical Metrology Impact and Analysis. Kimothi, S.K., Milwaukee: American Society for Quality,
2002.
IVC.7.13
Fundamentals of Analytical Chemistry, 8th Edition, Skoog, D.A., et al.
Brooks Cole, 2003.
IVC.7.14
Measurement Uncertainty Arising from Sampling: A Guide to
Methods and Approaches.
Eurachem/CITAC Guide, 1st edition, 2007.
IVC.7.15
ASTM E2655 Standard Guide for Reporting Uncertainty of Test Results and Use of the
Term Measurement Uncertainty in ASTM Test Methods.
SWGDRUG GLOSSARY OF TERMS AND DEFINITIONS
A.1
Introduction
This
glossary of terms and definitions has been developed and adopted by the SWGDRUG
core committee from a variety of sources that are listed in endnotes. In some instances, the core committee
modified existing definitions or created definitions where none could be found
in standard references.
A.2
Terms and definitions
A.2.1
accuracy
closeness of agreement between a test result or
measurement result and the true value
NOTE 1 In practice,
the accepted reference value is
substituted for the true value.
NOTE 2 The term
“accuracy”, when applied to a set of test or measurement results, involves a
combination of random components and a common systematic error or bias component.
NOTE 3 Accuracy
refers to a combination of trueness and
precision.
A.2.2
analyst
a designated person who:
·
examines
and analyzes seized drugs or related materials, or directs such examinations to
be done,
·
independently
has access to unsealed evidence in order to remove samples from the evidentiary
material for examination and,
·
as a consequence of such examinations, signs reports
for court or other purposes [SWGDRUG]
A.2.3
analyte
the component of a system to be
analyzed
A.2.4
audit
systematic,
independent and documented process for obtaining audit evidence and evaluating
it objectively to determine the extent to which audit criteria are fulfilled
A.2.5
bias
the
difference between the expectation of the test results and an accepted
reference value.
[ASTM E 177-06b, ASTM E456-06]
A.2.6
blank
specimen or sample not containing the
analyte or other interfering substances
A.2.7
byproduct
a secondary or incidental
product of a manufacturing process.
[Collins English Dictionary - Complete
& Unabridged 10th Edition]
A.2.8
calibration
operation that, under specified
conditions, in a first step, establishes a relation between the quantity values with measurement uncertainties provided by measurement standards and
corresponding indications with
associated measurement uncertainties
and, in a second step, uses this information
to establish a relation for obtaining
a measurement result from an
indication
NOTE 1 A calibration
may be expressed by a statement, calibration function, calibration diagram, calibration curve, or calibration table. In
some cases, it may consist of an additive or multiplicative correction of the indication with
associated measurement uncertainty.
NOTE 2 Calibration
should not be confused with adjustment
of a measuring system, often mistakenly called “self-calibration”, nor
with verification of
calibration.
[VIM 2008]
A.2.9
capacity
the amount of
finished product that could be produced, either in one batch or over a defined
period of time, and given a set list of variables.
A.2.10
catalyst
a substance whose presence
initiates or changes the rate of a chemical reaction, but does not itself enter
into the reaction.
A.2.11
certified
reference material (CRM)
reference material characterized by a metrologically valid procedure for one or more specified
properties, accompanied by a certificate that provides the value of the
specified property, its associated uncertainty, and a statement of metrological
traceability
NOTE 1 The concept of
value includes qualitative attributes such as identity or sequence.
Uncertainties for such attributes may be expressed as probabilities.
NOTE 2 Metrologically valid procedures for the production and
certification of reference materials are given in, among others, ISO Guides 34
and 35.
NOTE 3 ISO Guide 31
gives guidance on the contents of certificates.
NOTE 4 VIM has an
analogous definition (ISO/IEC Guide 99:2007, 5.14).
A.2.12
chain
of custody
procedures
and documents that account for the integrity of a specimen or sample by
tracking its handling and storage from its point of collection to its final
disposition
A.2.13
clandestine
secret and concealed, often for
illicit reasons.
[Collins English Dictionary - Complete &
Unabridged]
A.2.14
combined
standard uncertainty
standard uncertainty of the result of
a measurement when that result is obtained from the values of a number of other
quantities, equal to the positive square root of a sum of terms, the terms
being the variances or covariances of these other
quantities weighted according to how the measurement result varies with changes
in these quantities
[GUM 2008]
A.2.15
control
material of established origin that is
used to evaluate the performance of a test or comparison
A.2.16
deficiency
of analysis
any erroneous
analytical result or interpretation, or any unapproved deviation from an
established policy or procedure in an analysis
A.2.17
detection limit
the lowest concentration of analyte in
a sample that can be detected, but not necessarily quantitated under the stated
conditions of the test
A.2.18
expanded
uncertainty (U)
quantity defining an interval about a
result of a measurement that may be expected to encompass a large fraction of
the distribution of values that could reasonably be attributed to the measurand
NOTES
1. The fraction may
be regarded as the coverage probability or level of confidence of the interval.
2. To associate a
specific level of confidence with the interval defined by the expanded
uncertainty requires explicit or implicit assumptions regarding the probability
distribution characterized by the measurement result and its combined standard
uncertainty. The level of confidence that may be attributed to this interval
can be known only to the extent to which such assumptions can be justified.
3. An expanded
uncertainty U is calculated from a combined standard uncertainty uc and coverage factor k
using: U = k x uc
A.2.19
false negative
Test result that states that an
analyte is absent, when, in fact, it is present above the established limit of detection for the
analyte in question
A.2.20
false
positive
test result that states that an analyte is
present, when, in fact, it is not present or, is present in an amount less than
a threshold or designated cut-off concentration
A.2.21
finished product
a manufactured product ready
for use.
A.2.22
intermediate
substance that is manufactured
for and consumed in or used for chemical processing to be transformed into
another substance.
A.2.23
limit of detection
see
A.2.13 detection limit
A.2.24
limit of quantitation
the lowest
concentration of an analyte that can be determined with acceptable precision
(repeatability) and accuracy under the stated conditions of the test
A.2.25
linearity
defines the ability of the method to
obtain test results proportional to the concentration of analyte
NOTE The Linear Range is by inference the
range of analyte concentrations over which the method gives test results
proportional to the concentration of the analyte.
A.2.26
pharmaceutical
identifiers
physical characteristics of tablets,
capsules or packaging indicating the identity, manufacturer, or quantity of
substances present
A.2.27
population
the totality of items or units of
material under consideration
A.2.28
precision
closeness of agreement between independent test/measurement results obtained under stipulated conditions
NOTE 1 Precision
depends only on the distribution of random errors and does not relate to the true value or the specified
value.
NOTE 2 The measure of
precision is usually expressed in terms of imprecision and computed as a
standard deviation of the test results or
measurement results. Less precision is reflected by a
larger standard deviation.
NOTE 3 Quantitative
measures of precision depend critically on the stipulated conditions. Repeatability conditions and reproducibility conditions are particular sets
of extreme stipulated conditions.
A.2.29
precursor
a chemical that is transformed
into another compound, as in the course of a chemical reaction, and therefore
precedes that compound in the synthetic pathway.
[Webster’s
Unabridged Dictionary of the English Language]
A.2.30
procedure
specified way
to carry out an activity or process
1. Procedures can be documented or not.
2. When a procedure is documented, the term
“written procedure” or “documented procedure” is frequently used. The document that contains a procedure can be
called a “procedure document.”
A.2.31
proficiency
testing
ongoing process
in which a series of proficiency specimens or samples, the characteristics of
which are not known to the participants, are sent to laboratories on a regular
basis. Each laboratory is tested for its
accuracy in identifying the presence (or concentration) of the drug using its
usual procedures. An accreditation body
may specify participation in a particular proficiency testing scheme as a
requirement of accreditation.
A.2.32
qualitative
analysis
analysis in which substances are
identified or classified on the basis of their chemical or physical properties,
such as chemical reactivity, solubility, molecular weight, melting point,
radiative properties (emission, absorption), mass spectra, nuclear half-life,
etc. See also A.2.29 quantitative analysis
A.2.33
quality
assurance
part of
quality management focused on providing confidence that quality requirements
will be fulfilled.
A.2.34
quality
management
coordinated activities to direct and
control an organization with regard to quality
NOTE Direction and control with regard to quality
generally includes establishment of the quality policy and quality objectives,
quality planning, quality control, quality assurance and quality improvement.
NOTE Quality manuals can vary in detail and format
to suit the size and complexity of an individual organization.
A.2.36
quantitative
analysis
analyses in
which the amount or concentration of an analyte may be determined (estimated)
and expressed as a numerical value in appropriate units. Qualitative
analysis may take place without quantitative analysis, but quantitative
analysis requires the identification (qualification) of the analytes for which
numerical estimates are given
A.2.37
random
sample
the sample so selected that any
portion of the population has an equal (or known) chance of being chosen. Haphazard or arbitrary choice of units is
generally insufficient to guarantee randomness
A.2.38
reagent
a chemical used to react with
another chemical, often to confirm or deny the presence of the second chemical.
A.2.39
recovery
term used in
analytical and preparative chemistry to denote the fraction of the total
quantity of a substance recoverable following a chemical procedure
A.2.40
reference
material (RM)
material, sufficiently homogeneous and
stable with respect to one or more specified properties, which has been
established to be fit for its intended use in a measurement process
NOTE 1 RM is a
generic term.
NOTE 2 Properties can
be quantitative or qualitative, e.g. identity of substances or species.
NOTE 3 Uses may
include the calibration of a measurement system, assessment of a measurement
procedure, assigning values to other materials, and quality control.
NOTE 4 A single RM
cannot be used for both calibration and validation of results in the same
measurement procedure.
NOTE 5 VIM has an
analogous definition (ISO/IEC Guide 99:2007, 5.13), but restricts the term
“measurement” to apply to quantitative values and not to qualitative properties.
However, Note 3 of ISO/IEC Guide 99:2007, 5.13, specifically includes the
concept of qualitative attributes, called “nominal properties”.
A.2.41
repeatability (of results of measurements)
closeness of the agreement between the
results of successive measurements of the same measurand
carried out subject to all of the following conditions:
- the same measurement procedure;
- the same observer;
- the same measuring instrument, used
under the same conditions;
- the same location;
- repetition over a short period of
time.
A.2.42
reproducibility
(of results of measurements)
Closeness of the agreement between the
results of measurements of the same measurand, where
the measurements are carried out under changed conditions such as:
- principle or method of measurement;
- observer;
- measuring instrument;
- location;
- conditions of use;
- time.
A.2.43
robustness
the robustness of an analytical procedure is a measure of its capacity to remain unaffected by small, but deliberate variations in method parameters and provides an indication of its reliability during normal usage
A.2.44
ruggedness
The ruggedness
of an analytical method is the degree of reproducibility of test results
obtained by the analysis of the same samples under a variety of conditions,
such as different laboratories, analysts, instruments, lots of reagents,
elapsed assay times, assay temperatures, or days. Ruggedness is normally expressed as the lack
of influence on test results of operational and environmental variables of the
analytical method. Ruggedness is a
measure of reproducibility of test results under the variation in conditions
normally expected from laboratory to laboratory and from analyst to
analyst.
A.2.45
sample
subset of a population made up of one or more sampling units
NOTE 1 The sampling
units could be items, numerical values or even abstract entities depending on
the population of interest.
NOTE 2 The definition
of sample in ISO 3534-2 includes an example of a sampling frame which is
essential in drawing a random sample from a finite population.
A.2.46
sampling
act of drawing or constituting a sample
A.2.47
sampling
plan
a specific plan which states the
sample size(s) to be used and the associated criteria for accepting the lot
NOTES
1.
A criterion is, for example, that the
number of nonconforming items is less than or equal to the acceptance number.
2.
The sampling plan does not contain the
rules on how to take the sample.
[ISO 3534-2:1993 (E/F)]
A.2.48
sampling
procedure
operational requirements and/or
instructions relating to the use of a particular sampling plan; i.e., the
planned method of selection, withdrawal and preparation of sample(s) from a lot
to yield knowledge of the characteristic(s) of the lot
[ISO 3534-2:1993
(E/F)]
A.2.49
sampling scheme
a combination of sampling plans with
rules for changing from one plan to another
NOTE
Some schemes have switching rules for
automatic change to tightened inspection plans or reduced inspection plans or
change to 100 % inspection.
[ISO 3534-2:1993 (E/F)]
A.2.50
selectivity
(in analysis)
1.
(Qualitative): The extent to which other substances interfere with the
determination of a substance according
to a given procedure.
2.
(Quantitative): A term used in conjunction with another substantive
(e.g.
constant, coefficient, index, factor,
number) for the quantitative characterization of interferences.
A.2.51
standard
uncertainty
uncertainty of the result of a
measurement expressed as a standard deviation
[GUM 2008]
A.2.52
traceability
ability to trace the history,
application or location of that which is under consideration
NOTES
1. When
considering product, traceability can relate to
·
the origin of materials and parts,
·
the processing history, and
·
the distribution and location of the
product after delivery.
2. In
the field of metrology the definition in VIM:1993, 6.10, is the accepted
definition.
A.2.53
trueness
closeness of agreement between the
expectation of a test result or a measurement result
and a true value
NOTE 1 The measure of
trueness is usually expressed in terms of bias.
NOTE 2 Trueness is
sometimes referred to as “accuracy of the mean”. This usage is not recommended.
NOTE 3 In practice,
the accepted
reference value
is substituted for the true value.
A.2.54
uncertainty
(measurement)
parameter, associated with the measurement result, or test result, that characterizes the dispersion
of the values that could reasonably be attributed to the particular quantity
subject to measurement or characteristic subject
to test
NOTE 1 This
definition is consistent with VIM but differs from it in phrasing to fit into
this part of ISO 3534 concepts and to include the testing of characteristics.
NOTE 2 “Parameter” is
defined in ISO 3534-1. The parameter can be, for example, a standard deviation
or a given multiple of it.
NOTE 3 Uncertainty of
measurement or test comprises, in general, many components. Some of these
components can be estimated on the basis of the statistical distribution of the
results of a series of measurements and can be characterized by standard
deviations. Other components, which can also be characterized by standard
deviations, are evaluated from assumed probability distributions based on
experience or other information.
NOTE 4 Components of
uncertainty include those arising from systematic effects associated with
corrections and reference standards which contribute to the dispersion.
NOTE 5 Uncertainty is
distinguished from an estimate attached to a test or measurement result that
characterizes the range of values within which the expectation is asserted to
lie. The latter estimate is a measure of precision rather than of accuracy and should be used only when the true value is not defined. When
the expectation is used instead of the true value, the expression “random
component of uncertainty” is used.
A.2.55
uncorrelated techniques
Uncorrelated
techniques are those that yield uncorrelated measurements. In practice this is often achieved by using
techniques that have a different fundamental mechanism for characterization. For example, a gas chromatographic test based
on a partition mechanism and a thin layer chromatographic system based on an
adsorption mechanism would be considered uncorrelated techniques, but two gas
chromatographic tests based on a partition mechanism would not.
A.2.56
validation
confirmation,
through the provision of objective evidence, that the requirements for a
specific intended use or application have been fulfilled
NOTES
1. The
term “validated” is used to designate the corresponding status.
2. The
use conditions for validation can be real or simulated.
A.2.57
verification
confirmation,
through the provision of objective evidence, that specified requirements have
been fulfilled
NOTES
1. The
term “verified” is used to designate the corresponding status.
2. Confirmation
can comprise activities such as
·
performing alternative calculations,
·
comparing a new design specification
with a similar proven design specification,
·
undertaking tests and demonstrations,
and
·
reviewing documents prior to issue.
A.2.58
yield,
expected
the quantity of material or the
percentage of theoretical yield anticipated at any appropriate phase of
production based on previous laboratory, pilot scale, or manufacturing
data.
A.2.59
yield,
theoretical
the quantity that would be
produced at any appropriate phase of production based upon the quantity of
material to be used, in the absence of any loss or error in actual
production.
A.3.1
ASTM
D6161-10 Standard Terminology Used for Microfiltration, Ultrafiltration,
Nanofiltration and Reverse Osmosis Membrane
Processes, © ASTM International (ASTM), 100 Barr Harbor Drive, West
Conshohocken, PA 19428.
A.3.2
ASTM E456-08 Standard Terminology Relating to Quality and
Statistics
Annual Book of ASTM Standards 2005, Section Fourteen, General Methods and
Instrumentation, Vol 14.02 Published by the American Society For Testing And
Materials International USA.
A.3.3
ASTM
E1605-04 Standard Terminology Relating to
Lead in Buildings, © ASTM International (ASTM), 100 Barr Harbor Drive, West
Conshohocken, PA 19428.
A.3.4
ASTM
E1732-09
Standard Terminology Relating to Forensic Science Annual Book of ASTM
Standards 2005, Section Fourteen, General Methods and Instrumentation, Vol
14.02 Published by the American Society For Testing And Materials International
USA.
A.3.5
ASTM
E2363-06A Standard Terminology Relating
to Process Analytical Technology in the Pharmaceutical Industry, © ASTM
International (ASTM), 100 Barr Harbor Drive, West Conshohocken, PA 19428.
A.3.6
ASTM
F2725-11 Standard Guide for European
Union's Registration, Evaluation, and Authorization of Chemicals (REACH) Supply
Chain Information Exchange, © ASTM International (ASTM), 100 Barr Harbor
Drive, West Conshohocken, PA 19428.
A.3.7
Collins
English Dictionary – Complete and Unabridged, 10th Ed., New York,
New York, HarperCollins Publishers, 2003.
A.3.8
EURACHEM, The Fitness for
Purpose of Analytical Methods English Edition, Developed by EURACHEM
Working Group. Supported in part under
contract with UK Department of Trade and Industry as part of the National
Measurement System Valid Analytical Measurement (VAM) Programme
1998.
A.3.9
ISO
3534-1:2006 (E/F), INTERNATIONAL STANDARD 2nd
ed. Statistics – Vocabulary and symbols Part 1: General
statistical terms and terms used in probability, Published by the International Organization for
Standardization, Switzerland 2006.
A.3.10
ISO 3534-2:2006 (E/F), INTERNATIONAL STANDARD 2nd ed.Statistics
— Vocabulary and symbols Part 2: Applied
statistics Published by the International
Organization for Standardization, Switzerland 2006.
A.3.11
ISO GUIDE 30:1992 (E/F), GUIDE 30 Terms and
definitions used in connection with reference materials 2nd Ed.,
Published by the International Organization for Standardization, Switzerland
1992. ISO GUIDE 30:1992(E)/Amd.1:2008, Amendment 1 Revision of definitions
for reference material and certified reference material.
A.3.12
GUM, Evaluation of measurement data — Guide to the
expression of uncertainty in measurement Published by the Joint
Committee for Guides in Metrology (JCGM), JCGM 100:2008.
A.3.13
ISO 9000:2005 (E), INTERNATIONAL
STANDARD Quality management systems—Fundamentals and vocabulary Published
by the International Organization for Standardization, Switzerland 2005.
A.3.14
IUPAC, Entries are from the
online version of the IUPAC Compendium of Chemical Terminology that mostly corresponds
to the second edition (1997), compiled by Alan D. McNaught
and Andrew Wilkinson (Royal Society of Chemistry, Cambridge, UK).
A.3.15
SWGDRUG, Definitions developed by the core committee of the
Scientific Working Group for the Analysis of Seized Drugs.
A.3.16
UNODC, GLOSSARY OF TERMS FOR
QUALITY ASSURANCE AND GOOD LABORATORY PRACTICES Published by The United
Nations International Drug Control Programme, Vienna
1995.
A.3.17
USP 28:2005, THE UNITED STATES PHARMACOPOEIA
28TH Rev. Published by the United States Pharmacopoeial
Convention Inc. USA 2005.
A.3.18
VIM, International Vocabulary of Basic and
General Terms in Metrology Published by the International Organization for
Standardization, Switzerland.
A.3.19
Webster’s
Unabridged Dictionary of the English Language, New York, New York, Random House
Reference Press, 2001.
A.3.20
General requirements
for the competence of testing and calibration laboratories,
International Organization for Standardization, ISO/IEC 17025: 2005.
A.3.21
General requirements
for the competence of reference material producers, International Organization for
Standardization, ISO Guide 34:2009.
End of
Document