4.4 Design of proficiency testing schemes
4.4.1 Planning
4.4.1.1 The proficiency testing provider shall identify and plan those processes which directly affect the
quality of the proficiency testing scheme and shall ensure that they are carried out in accordance with
prescribed procedures.
NOTE Stakeholders' interests can be considered in developing a plan and relevant information.
4.4.1.2 The proficiency testing provider shall not subcontract the planning of the proficiency testing
scheme (see 5.5.2).
NOTE The proficiency testing provider can utilize advice or assistance from any advisors, experts or steering group
(see 4.4.1.4).
4.4.1.3 The proficiency testing provider shall document a plan before commencement of the proficiency
testing scheme that addresses the objectives, purpose and basic design of the proficiency testing scheme,
including the following information and, where appropriate, reasons for its selection or exclusion:
a) the name and address of the proficiency testing provider;
b) the name, address and affiliation of the coordinator and other personnel involved in the design and
operation of the proficiency testing scheme;
c) the activities to be subcontracted and the names and addresses of subcontractors involved in the
operation of the proficiency testing scheme;
d) criteria to be met for participation;
e) the number and type of expected participants in the proficiency testing scheme;
f) selection of the measurand(s) or characteristic(s) of interest, including information on what the
participants are to identify, measure, or test for in the specific proficiency testing round;
g) a description of the range of values or characteristics, or both, to be expected for the proficiency test
items;
h) the potential major sources of errors involved in the area of proficiency testing offered;
i) requirements for the production, quality control, storage and distribution of proficiency test items;
j) reasonable precautions to prevent collusion between participants or falsification of results, and
procedures to be employed if collusion or falsification of results is suspected;
k) a description of the information which is to be supplied to participants and the time schedule for the
various phases of the proficiency testing scheme;
l) for continuous proficiency testing schemes, the frequency or dates upon which proficiency test items are
to be distributed to participants, the deadlines for the return of results by participants and, where
appropriate, the dates on which testing or measurement is to be carried out by participants;
m) any information on methods or procedures which participants need to use to prepare the test material and
perform the tests or measurements;
n) procedures for the test or measurement methods to be used for the homogeneity and stability testing of
proficiency test items and, where applicable, to determine their biological viability;
o) preparation of any standardized reporting formats to be used by participants;
p) a detailed description of the statistical analysis to be used;
q) the origin, metrological traceability and measurement uncertainty of any assigned values;
r) criteria for the evaluation of performance of participants;
s) a description of the data, interim reports or information to be returned to participants;
t) a description of the extent to which participant results, and the conclusions that will be based on the
outcome of the proficiency testing scheme, are to be made public; and
u) actions to be taken in the case of lost or damaged proficiency test items.