522 – Contributed Oral Poster Presentations: Biopharmaceutical Section
Precision Study for a Qualitative Assay
Paul Hshieh
FDA/CBER
Tie-Hua Ng
FDA/CBER
CLSI (Clinical Laboratory Standards Institute) guideline EP5-A2 defines precision as closeness of agreement between independent test/measurement results obtained under stipulated conditions. Although the statistical analysis of the precision study for a quantitative assay is well-developed, it is not clear how the precision study for a qualitative assay be analyzed. One approach commonly used for a qualitative assay is based on percent agreement of the test results as compared with the known result. A 100% agreement is the best possible outcome one could hope for and would imply 100% agreement between all the test results. However, the interpretation of the results becomes difficult when less than perfect agreement is observed because percent agreement with the known results does not provide individual precision components.
