Evaluation of quality of diagnostic kit for hepatitis B virus surface antigen by trend analysis

Objective To evaluate the quality of domestic diagnostic kit for hepatitis B virus surface antigen(HBsAg)by trend analysis. Methods The lot release data of diagnostic kit for HBsAg,collected from four manufacturers using the same batch of national standard,were analyzed retrospectively. Trend analysis was performed on the determination results of test samples of various serotypes at various concentrations. The value of mean ± 2 SD was used as the warning threshold,while the value of mean ± 3 SD as the action threshold. The change trends of quality indexes of the kits were observed. The data were defined as deviation from the data set if the determination result was beyond the action threshold,the determination results of three consecutive batches of samples were beyond the warning threshold or the determination result showed a trend of severe drift(the determination results of six consecutive batches of samples increase or decrease,or those of eight consecutive batches are on the same side of mean). Results During an observation period from March 2011 to May 2013,the determination results of 8 ~ 10 batches of kits A,B and C were on the same side of mean,indicating deviation of data. However,no severe data drift was observed in any batch of kit D. Conclusion Trend analysis reflected the change of quality of diagnostic kit for HBsAg,which provided a tool for ensuring the stability of quality of the kit.