The following definitions were developed and adopted by the Scientific
Working Group for the Analysis of Seized Drugs core committee from
a variety of sources including the United Nations International
Drug Control Programme's Glossary of Terms for Quality Assurance
and Good Laboratory Practices, United Nations, 1995.
Accreditation is the procedure by which an accreditation
body formally recognizes that a laboratory or person is competent
to carry out specific tasks.
Accreditation body is an independent science-based organization
that has the authority to grant accreditation.
Accuracy is composed of trueness and precision.
Analysis is the technical operation
to determine one or more characteristics of, or to evaluate the
performance of, a given product, material, equipment, physical phenomenon,
process, or service according to a specified procedure.
Analyst is a designated person who
- Independently has access to unsealed evidence in order to remove
samples from the evidence for examination.
- Examines and analyses seized drugs or related materials or directs
such examinations to be done.
- As a consequence of such examinations, signs reports for court
or other purposes.
Audit is a review conducted to compare the various aspects
of the laboratory's performance with a standard for that performance.
Blank is a specimen or sample not containing the analyte.
Calibration is a set of operations that establishes under
specified conditions the relationship between values indicated by
a measuring instrument or measuring system or values represented
by a material measure and the corresponding known values of a measurand.
Certified reference material is reference material, one
or more of whose property values have been certified by a technical
procedure, accompanied by or traceable to a certificate or other
documentation that has been issued by a certifying body.
Certifying body is an independent science-based organization
that has the competence to grant certification.
Chain of custody are procedures and
documents that account for the integrity of a sample by tracking
its handling and storage from the point of collection to final disposition.
Control sample is a standard of comparison for verifying
or checking the findings of an experiment.
Controls are samples used to determine the validity of the
calibration, that is, the linearity and stability of a quantitative
test or determination over time. Controls are either prepared from
the reference material (separately from the calibrators, that is,
weighed or measured separately), purchased, or obtained from a pool
of previously analyzed samples. When possible, controls should be
matrix-matched to samples and calibrators.
Correlated techniques are those that have the same fundamental
mechanism of characterization. For example, this would prevent the
choice of two gas chromatographic tests both based on a partition
mechanism (e.g., methylsiloxane and phenylmethylsiloxane) or two
thin layer chromatographic systems both based on an adsorption mechanism.
Deficiency of analysis is any erroneous analytical result
or interpretation or any unapproved deviation from an established
policy or procedure in an analysis.
False positive is a test result that states a drug is present
when, in fact, such a drug is not present in an amount less than
a threshold or designated cut-off concentration.
Health and safety manager is a designated person who is
responsible for maintaining the laboratory's health and safety
program (including an annual review of the program) and who monitors
compliance with the program.
Independent test result is a result obtained in a manner
not influenced by any previous results on the same or similar material.
Laboratory is a facility where analyses are performed by
qualified personnel using adequate equipment.
Limit of detection is the smallest measured content from
which it is possible to deduce the presence of the analyte with
reasonable statistical certainty.
Limit of quantitation is the lowest concentration of analyte
that can be determined with an acceptable level of precision and
Linearity defines the ability of the method to obtain test
results proportional to the concentration of the analyte.
Method is a detailed, defined procedure for performing an
analysis. See Procedure
Procedure is a specified, documented
way to perform an activity.
Proficiency testing is the 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.
Qualitative analysis is a test that determines the presence
or absence of specific drugs in the sample.
Qualitative test See Qualitative
Quality assurance is a system of activities whose purpose
is to provide, to the producer or user of a product or a service,
the assurance that it meets defined standards of quality with a
stated level of confidence.
Quality assurance manager is a designated person who is
responsible for maintaining the quality management system and who
monitors compliance with the program.
Quality management is that aspect of the overall management
function that determines and implements the quality policy.
Quality manual is a document stating the general quality
policies, procedures, and practices of an organization.
Quantitative analysis is a procedure to determine the quantity
of drug present in a sample.
Quantitative test See Quantitative
Range is a set of concentrations of the analyte in which
the error of a method is intended to lie within specified limits.
Reference material is a material or substance, one or more
properties of which are sufficiently well established to be used
for calibrating an apparatus, assessing a measurement method, or
assigning values to materials.
Repeatability is the closeness of the agreement between
the results of successive measurements of the same measurand carried
out under the same conditions of measurement.
Report is a document containing a formal statement of results
of tests carried out by a laboratory.
Representative sample is statistically, a sample that is
similar to the population from which it was drawn. When a sample
is representative, it can be used to make inferences about the population.
The most effective way to get a representative sample is to use
random methods to draw it. Analytically, it is a sample that is
a portion of the original material selected in such a way that is
possible to relate the analytical results obtained from it to the
properties of the original material.
Reproducibility is the closeness of agreement between the
results of successive measurements of the same analyte in identical
material made by the same method under different conditions (e.g.,
different operators and different laboratories and considerably
separated in time).
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.
Sample is a portion of the whole material to be tested.
Statistically, it is a set of data obtained from a population.
Sampling is analytically the whole set of operations needed
to obtain a sample, including planning, collecting, recording, labeling,
sealing, and shipping. Statistically, it is the process of determining
properties of the whole population by collecting and analyzing data
from a representative segment of it.
Selectivity is the extent to which a method can determine
particular analyte(s) in a mixture without interference from the
other components in the mixture. A method that is perfectly selective
for an analyte or group of analytes is said to be specific.
Specificity See Selectivity
Standard operating procedures are written documents that
detail the methods of an operation, analysis, or action whose techniques
and procedures are thoroughly prescribed and that is accepted as
the method for performing certain routine or repetitive tasks.
Supervisory chemist is a designated person who has the overall
responsibility and authority for the technical operations of the
drug analysis section.
Technician or assistant analyst is a person who analyses
evidence but does not issue reports for court purposes.
Technical support personnel are people who perform basic
laboratory duties but do not analyze evidence.
Test See Analysis
Traceability is the property of a result of a measurement
whereby it can be related to appropriate standards, generally international
or national standards, through an unbroken chain of comparisons.
Traceable is the ability to trace the history, application,
or location of an entity by means of recorded identification. See
also Chain of custody
Trueness is the closeness of agreement between the average
value obtained from a large set of test results and an accepted
Uncertainty is a parameter associated with the result of
a measurement that characterizes the dispersion of the values that
could reasonably be attributed to the measurand.
Validation is confirmation by examination and provision
of objective evidence that the particular requirements for a specific
intended use are fulfilled.
Verification is confirmation by examination and provision
of objective evidence that specified requirements have been fulfilled.
(A method works in any laboratory as well as in the laboratory where
it was validated.)