Foreword
Introduction
1 Scope
2 Normative references
3 Concepts
4 Symbols
5 Designation
6 Requirements relating to proficiency testing scheme
6.1 Coordinating body
6.2 Testing laboratory
6.3 Coordinator
6.4 Other staff
6.5 Confidentiality
6.6 Equipment
6.7 Documentation of quality system
6.8 Advisory group
7 Requirements relating to test participants
8 Design of proficiency test
8.1 Test specification
8.2 Sample selection
8.3 Parameter selection
8.4 Spiking
8.5 Number of participants
8.6 Number of samples
8.7 Replicate measurements and sample size
9 Procedure
9.1 General
9.2 Sample preparation
9.3 Stability and homogeneity testing
9.4 Prevention of collusion between participants
9.5 Analytical methods
9.6 Specification of conventional true value
9.7 Sample distribution
9.8 Communication with participants
10 Evaluation of interlaboratory tests
10.1 General requirements
10.2 General statistical evaluation procedure
10.3 Robust analysis
10.4 Variance function
10.5 z-scores
11 Expression of results
12 Archiving and managing the results
Annex A Example elucidating the principle behind the
Q-method of estimation
Annex B Example of evaluation in accordance with clause 10
Annex C Example of calculating the variance function
Explanatory notes
Bibliography