Clinical laboratories around the world reporting determination results deeply depend on only once determining for each analyte for each specimen. This approach only occurs in clinical laboratories in the world, it is the main characteristic of clinical laboratory, however, there also are disadvantages. Relative determinations should be performed again when clinicians and patients have doubts about the reports. The re-determination results are consistent with previous reports, which is the best result. To ensure the quality of determination results and meet the requirements of clinic and patients, clinical laboratories must pay full attention to the precision performance of measurement system, as the primary analytical performance of quantitative analysis. Unfortunately, today's clinical laboratories and in vitro diagnostic manufacturers have not done well precision experiments. This paper calls for the careful study of the Clinical and Laboratory Standards Institute (CLSI) EP5 document, and establishes or verifies the precision performance of each analyte measurement system for determining patient specimen, and this is the key to ensure the quality of determination results for clinic and patients. This paper describes the use of chi-square test for standard deviation when verifying the precision performance from manufacturers as well.
