Proficiency Testing
What is PT ?
Proficiency testing by inter-laboratory comparisons is used to determine the performance of individual laboratories for specific tests or measurements, and to monitor the continuing performance of laboratories. ISO/IEC 17043 should be consulted for a full exposition of the purposes of proficiency testing.
Terms:
Proficiency testing
Evaluation of participant performance against preestablished criteria by means of interlaboratory comparisons:
– Quantitative / qualitative
– Single item (sequential) / bulk interlaboratory
– Single occasion / continuous
– Sampling
– Data transformation and interpretation
Proficiency testing scheme
Proficiency testing designed and operated in one or more rounds for a specified area of testing, measurement, calibration or inspection.
Proficiency test item
Sample, product, artefact, reference material, piece of equipment, measurement standard, data set or other information used for proficiency testing.
Proficiency testing provider
Organization which takes responsibility for all tasks in the development and operation of a proficiency testing scheme.
Participant
Laboratory, organization or individual, that receives proficiency test items and submits results for review by the proficiency testing provider.
Assigned value
Value attributed to a particular quantity and accepted, sometimes by convention, as having an uncertainty appropriate for a given purpose.
Standard deviation for proficiency assessment
Measure of dispersion used in the assessment of proficiency, based on the available information.
Z-score
Standardized measure of laboratory bias, calculated using the assigned value and the standard deviation for proficiency assessment.
Outlier
Observation in a set of data that appears to be inconsistent with the remainder of that set.