SWGDRUG Meeting Minutes
January 26-28, 2010
Core
Committee Members (present):
Nelson
A. Santos, Drug Enforcement Administration, Chair
Scott R.
Oulton, Drug Enforcement Administration, Secretariat
Susan Ballou, National Institute of Standards and
Technology (NIST)
Suzanne Bell, West Virginia
University
Michael Bovens, European Network of Forensic Science
Institutes (ENFSI)
Sylvia
Burns, Forensic Science
Garth Glassburg, American Society of Crime Laboratory
Directors (ASCLD)
Linda
Jackson, Mid-Atlantic Association of Forensic Scientists
Richard
Laing, Health
Jack
Mario, Northeastern Association of Forensic Scientists and
American Society for Testing Materials (
Jerry Massetti, Northwestern Association of Forensic
Scientists and
Christian
Matchett, Southern
Association of Forensic Scientists
Osama Ohtsuru, National Research Institute of Police
Richard Paulas, Midwestern Association of Forensic
Scientists
Sandra E. Rodriguez-Cruz, Drug Enforcement Administration
Scott Vajdos, Southwestern Association of Forensic
Scientists
Eileen Waninger, Federal Bureau of Investigation
Udo Zerell, Bundeskriminalamt, Germany
Core
Committee Members (not present):
Iphigenia
Naidis, United Nations
Office on Drugs and Crime (UNODC)
Robert
Powers, Connecticut Department of Public Safety
Catherine
Quinn,
Invited
Guests:
Mark Ruefenacht, Heusser Neweigh
Bradley Venner, Environmental Protection Agency,
Denver, CO
January
26, 2010 (Tuesday):
8:30 am SWGDRUG chair Nelson A. Santos opened the meeting by
thanking core members for their attendance, and introducing meeting guests
Bradley Venner (Statistician from EPA) and Mark Ruefenacht (Metrologist from Heusser Neweigh).
Mr.
Santos also thanked and acknowledged current support of SWGDRUG by
the Office of Forensic Sciences of the Drug Enforcement Administration (DEA).
Mr. Santos also briefly discussed the recent
scientific working groups (SWGs) meeting at the FBI. He commented on future proposals and changes
to other SWGs and how SWGDRUG is regarded as an example of how SWGs should operate.
SWGDRUG secretariat Scott R. Oulton provided
guidelines to core committee members regarding travel vouchers. Mr. Oulton also introduced guest Sandra E.
Rodriguez-Cruz, invited to assist during the meeting as notetaker.
8:45 am Suzanne Bell presented an update
of the Supplemental Uncertainty Document.
She discussed comments and revisions received from scientists at NIST
and summarized significant changes to the current version of the document. Among other subjects, a discussion ensued
regarding buoyancy effects and the consideration of correlated events during
the weighing of multiple units.
9:10 am Mr. Mark Ruefenacht
delivered a presentation on Metrology and Uncertainty. His presentation included a general
introduction to the subjects as well as discussions regarding upcoming ASCLD
recommendations, traceability, GUM requirements, static vs. dynamic weighing, and
measurement assurance procedures that he believes should be considered when
estimating uncertainty of weights in the forensic chemistry laboratory. Mr. Ruefenacht
emphasized the need to evaluate the significance of all sources of uncertainty. He recommended that crime laboratories
attempt eliminating or decreasing large sources of uncertainty (beach vs. ping-pong
balls analogy).
Mr. Ruefenacht
presented to the committee examples of measurement assurance procedures and
discussed their appropriateness for estimating the uncertainty of net weight
measurements in the forensic chemistry laboratory. Comparisons between the weighing of traceable
standard weights and bags of powder were presented. Mr. Ruefenacht
emphasized that laboratories should attempt to simulate routine weighing
procedures while estimating uncertainty.
Mr. Ruefenacht also discussed weighing
verification and validation procedures, and recommended the establishment of a
strong proficiency testing program in forensic laboratories, emphasizing not
only measurements but also traceability in the process.
10:15 BREAK
10:30 am Invited guest Dr. Bradley Venner delivered a presentation on Uncertainty. He discussed the philosophical nature of uncertainty
and its dependence on random and systematic effects. Dr. Venner echoed
the recommendations by Mr. Ruefenacht in regards to
validation and proficiency testing studies and how they could be of great use
to forensic chemistry laboratories attempting to estimate the uncertainty of
their measurements. Dr. Venner also discussed the use of control charts in the
laboratory. It was his opinion that
control charts are not as valuable for providing uncertainty estimates as they
are for providing a check or verification of uncertainty estimates established
through other means.
Dr. Venner also
provided comments resulting from his review of the supplemental uncertainty
document. He emphasized on the subjects
of readability, repeatability, linearity, and temperature sensitivity. A discussion ensued regarding the inclusion
of the temperature sensitivity factor as part of the uncertainty budget for net
weights.
12:00 pm LUNCH BREAK
3:10 pm BREAK
3:30 pm Review of
Supplemental Uncertainty Document continued.
January 27, 2010 (Wednesday):
8:30 am Review of Supplemental Uncertainty
Document continued.
Mark Ruefenacht discussed
comments received from Val Miller and William Guthrie from NIST. They recommend use of the ‘hybrid’ equation
for estimation of net weight uncertainty.
The ‘hybrid’ model treats individual weighing events as correlated
quantities (linear addition), while assuming independence (uncorrelated; RSS
model) between factors like balance calibration, repeatability, linearity, etc.,
to be considered within the uncertainty budget.
Dr. Venner
presented results from calculations he performed the previous night. He discussed that the ‘hybrid’ and the
‘completely-correlated’ models converge at high number of measurements, with
the dominant difference being the use of a factor of 30 versus √30, as
being considered for ‘Example 3’ of the document.
The committee discussed advantages,
disadvantages and implications of using the different models. The committee decided to recommend the
‘hybrid’ approach for the examples illustrated in the document.
Suzanne Bell will make changes/revisions to
the current document, pending further review by uncertainty Sub-committee and
final approval by core committee.
10:00 am BREAK
10:30 am Linda Jackson
- Editorial/Communications Subcommittee Update
Ms. Jackson presented comments received from
general forensic community regarding current SWGDRUG ‘Recommendations’.
Mr. Jack Mario communicated concerns regarding
the use of the terms ‘statistically-based’ or ‘probabilistic-based’ and the use
of the terms ‘frequentist’ vs
‘Bayesian’ approaches.
Ms. Jackson proceeded to present revisions
to “Recommendations” based on comments received. The following sections were revised:
·
Introduction
– minor administrative revisions
·
Education
and Training:
o
Clarification
regarding classes vs. laboratory requirements
o
Use of
‘degree program’ revised to read ‘coursework’
o
Recommendation
for 20 hours of training – revised language regarding training pertaining to
ancillary duties.
·
Sampling:
o
Editorial
revisions (numbering, lettering, etc.)
·
Methods:
o
Revised
to clarify classification of Categories A through C techniques based on
discriminating power.
·
Quality
Assurance:
o
Revision
to clarify that ‘Recommendations’ address both qualitative and quantitative
analysis
o
Minor
editorial revisions regarding documentation for reagent preparation, competency,
and proficiency testing.
·
Quality
Assurance / Uncertainty:
o
Application
of uncertainty – text revised to read “Standards Developing Organizations
(SDO)”
o
Qualitative
Measurements: text revised to include
“see examples in section 5.2)” so that qualitative examples are not missed.
o
Minor
editorial revisions in accordance to recent changes to Supplemental Uncertainty
Document.
o
Definitions: text revised for definition of false
negative.
o
Bibliography:
revised to include latest versions of GUM and VIM.
·
Reporting: Committee discussed possible future
directions as result of 2009 NAS Report.
12:30 pm LUNCH BREAK
1:30 pm Mr. Ruefenacht presented to
the committee that NIST offered to review the current version of the Supplemental
Uncertainty Document. Committee members
discussed the offer and agreed to review by NIST. Mr. Ruefenacht
volunteered to forward the latest version of document to NIST.
The core committee discussed
the future direction and final approval (voting) of the Supplemental
Uncertainty Document.
Review
of the Supplemental Uncertainty Document continued.
2:10
pm Christian Matchett – Presented a status update on current
The
Mr. Laing
presented the current training outline and example template illustrating future
contents, links, pictures, resources, etc.
Mr. Laing
commented on the project difficulties encountered in the last six months. A discussion ensued regarding the use of the
DEA’s current training program as a template or starting point for the SWGDRUG
training program.
Mr.
Santos and Ms. Rodriguez-Cruz presented an overview of the DEA Training
Program.
A
copy of DEA’s Training Program was provided to Mr. Laing.
3:00 pm BREAK
3:20
pm Mr. Ruefenacht
discussed his review of SWGDRUG’s main document (Recommendations) and presented
his comments.
3:40
pm Mr. Jack Mario presented
and discussed comments received from
Mr. Mario also
provided copies of recently published
Mr. Bovens presented a final list of projects being submitted
to ENFSI from countries within the European Union. Projects include a ’European Forensic
Education & Training Network’ through which training will be performed.
Mr. Bovens also briefly discussed
a current ENFSI project involving estimation of uncertainty arising from
sampling for quantitative analysis of drugs.
January 28, 2010 (Thursday):
10:15 am Core
committee members meet back in conference room.
Review of latest version of Supplemental
Uncertainty Document.
Linda Jackson presented a motion to accept
the current Supplemental Uncertainty Document, pending editorial review.
Motion was seconded by Mr. Garth Glassburg.
Vote:
All present SWGDRUG members unanimously approved the current version of
the document, pending editorial review.
It is to be noted that the editorial review
will include review of the document by subject-matter experts. The Editorial Sub-committee will evaluate
results from the editorial review and will make a final decision regarding
incorporation of any suggested changes.
11:45 am LUNCH BREAK
Revisions to the glossary are needed in
order to incorporate the most recent revisions to the GUM, VIM, ISO GUIDE 30:2008,
ISO 3534-1:1993, ISO 3534-2:2006, and other internationally accepted documents.
The following definitions were revised: accuracy,
bias, calibration, chain of custody, population (new
definition), precision, reference material, repeatability, reproducibility, sample,
sampling, selectivity, trueness, and validation.
The committee decided to keep using the
current definitions for sampling plan, procedure and scheme, as the core
committee believed them to be more appropriate for their intended use.
Some glossary definitions remained the same
and only the source reference was updated.
1:50 pm Mr. Laing presented a motion to accept current revisions
to the SWGDRUG Recommendations to include changes in the glossary.
Mr.
Paulas seconded the motion.
All
present members unanimously approved the motion to accept current revisions.
Sub-committee members will evaluate
current references included in DEA’s Training Program to determine which ones
are to be incorporated in SWGDRUG’s program.
The Sub-committee will also prepare a list of references that need to be
purchased.
Ms. Sue Ballou
suggested a future project to include recommendations to the drug analysis
community regarding laboratory reports.
Scott R. Oulton discussed
on-going efforts (from ASLCLD/
It was suggested
to the members of the Editorial Sub-committee to start exploring the issue of
reporting.
3:00 pm BREAK
3:15 pm Scott R. Oulton provided update
on SWGDRUG website. Recent revisions
include addition of uncertainty references provided by Mr. Ruefenacht
earlier in the week.
Michael Bovens
commented on recent cases of anthrax-contaminated heroin in Europe. Causes for the contamination have not been determined
yet.
3:30 pm Nelson Santos commented on possible replacements for
Dr. Tindall (retired) and requested suggestions from
committee members for possible replacements.
The members will send proposed names to the SWGDRUG chair.
Mr. Santos will also continue efforts
to invite SWGDRUG representative from Central and/or South America.
Mr. Santos requested suggestions for
possible locations for next SWGDRUG meeting.
The meeting is scheduled to be held during the week of July 5-9, 2010.
Mr. Santos officially welcomed
Mr. Scott Vajdos as a member of the SWGDRUG core
committee, representing the Southwestern Association of Forensic Scientists and
Harris County Medical Examiner’s Office.
Mr. Santos thanked guest Ms. Rodriguez-Cruz
for her contributions during the three-day meeting and welcomed her as a new
member of the SWGDRUG core committee.
4:00 pm Nelson
Santos thanked the committee for their hard-work and dedication to achieving
the goals of the meeting.
Meeting
adjourned.
Minutes respectfully submitted by Sandra E.
Rodriguez-Cruz on February 10, 2010.