EVALUATING ASSAY PRECISION FOR IMMUNO-CHEMILUMINESCENT METHOD FOR FOLLICLE-STIMULATINGHORMONE (FSH)

Abstract

Verification process of the methods according to the needs of ISO 17025 Standard includes evaluating the imprecision of theassay(S). For this purpose it is necessary to assess the repeatability (within-run) and total within-run laboratory precision.According to the CLSI EP15-A2 document the user of the test(s) should undertake the measurements of the analyte(s) at at-least two levels, by running of three replicates over five days. The purpose of our work was to estimate the assay precision ofthe immune-chemiluminiscent method for FSH quantification by estimating of repeatability and within-laboratory precisionas well as, to evaluate the obtained results.Material of our study were control samples, different from those used to ensure that the instrument is in control at the timeof the assessment, with two levels (low and high), which were run in duplicate as three replicates for 5 consecutive daysusing Immulite/Immulite 1000 Simens kits. The repeatability value for the low replicates was 0.30 miU/ml and for the highreplicates 2.1 miU/ml. Estimated repeatability value for the high level was less than the manufacturer’s verification valueclaims (2.1 and 2.5 respectively). Estimated repeatability verification value for the low level of replicates is similar to theverification value of the manufacturer’s claim (0.3 and 0.27 respectively). Estimated within-laboratory precision for the lowreplicates was 0.6 miU/ml and for the high 3.32 miU/ml.Evaluated within-laboratory precision verification value for the low replicates was 0.42 that is less than the manufacturer’sclaimed verification value of 2.68. For the high level replicates evaluated verification value was 2.67 less than themanufacturer’s claim (13.88).Our data have confirmed that the method is suitable for the purposes of the Standard and that repeatability and within-laboratory precision verification values are consistent with the manufacturer’s claims.