| Objective To validate whether the performance of hepatitis C virus nucleic acid quantitative assay kit matches the analytical performance promised by the manufacturer at changed detection limits. Methods According to the performance validation program based on the WS/T420-2013 protocol of the Clinical Laboratory for Commercial Quantification Kit, the verification procedure was performed by using HCV RNA standards for reference and clinical specimens of different concentrations that were collected from Beijing Ditan Hospital affiliated to Capital Medical University. The performance of hepatitis C virus nucleic acid quantitative assay kit was methodologically verified and evaluated through detecting the accuracy, precision, linearity, detection limit and anti-interference ability of reagents. Results In the accuracy verification, the regression equation was y=0.9881x-0.0972, R=0.998＞0.95, and the detected value was highly correlated with the reference value. In the precision verification, the intra-assay precision %CV value (1.86%, 2.64%) and the inter-assay precision %CV value (1.44%, 2.36%) of both high-concentration and low-concentration specimens were all≤5%, which met the requirements. In the linearity verification, the linear range of 2.50E+2 to 5.00E+7 IU/ml was valid. In the detection limit verification, samples at a concentration of 50 IU/ml were repeatedly measured 30 times, and 27 of the test results were positive, with a positive rate of 90% (27/30), which met the clinical requirements. In the anti-interference ability verification, the test values of serum samples with or without interfering substances were compared, and the absolute deviation of tests was less than ±0.5 lg, which met the clinical requirements. Conclusions When detection limits of an assay kit are revised, the laboratory should focus on a comprehensive evaluation of the analytical performance of the revised items, to judge whether the results match the analytical performance claimed by the manufacturer. At the same time, all other performance indicators of the reagents are validated according to the health industry standards. |