Optimization of HBsAg retesting process: an improvement in laboratory management system based on health economics.

OBJECTIVE: To optimize the retesting process for hepatitis B screening, reduce false positives in samples with weak positive signals, and improve the laboratory management system, ensuring no missed cases and eliminating resource waste. METHODS: 131 HBsAg-positive samples with initial signal to cut-off (S/CO) values ranging from 0.05 to 10 were divided into 5 intervals. After high-speed centrifugation, the samples were retested for HBsAg, and the initial and retest results were compared. By evaluating the repeatability and accuracy of the HBsAg results in different intervals, the "gray zone" of the HBsAg screening test was identified, and a laboratory optimization process plan was established. The new plan was piloted in parallel with the old plan to assess the reliability of the new plan. RESULTS: In the interval of initial cutoff (S/CO) values [0.05∼0.2], the difference rate between the initial test group and retest group was the highest (40%), and there was a significant difference in the qualitative results (p<0.01). In the interval (1,2], although there was no significant difference in the qualitative results before and after the retest (p=0.47), there were two samples with qualitative differences in the two groups. Under the new plan, the missed detection rate was reduced to 0, and it had excellent clinical application effects. CONCLUSION: On the premise of ensuring 0 missed detection, fully considering the economic benefits and the rational allocation of resources, the hepatitis B screening "gray zone" is set to [0.05,2]. For "gray zone" specimens, the retesting process must be implemented.