All test kits were approved and licensed by the Chinese State Food and Drug Administration (or Food and Drug Administration, FDA). The reagents used for donor screening tests are listed in Table 1, and the assays were performed following the manufacturer’s instructions.Table 1Screening Test Kits for HBsAg Used at Each Blood CenterBlood CenterFirst AssaySecond AssayTest KitSensitivity (%) / Specificity (%) / Limit (ng/ml)Test KitSensitivity (%) /Specificity (%) / Limit (ng/ml)AnhuiWANTAI (Beijing)99.5 / 98.5 / 0.03BIO-RAD (United States)100 / 97.55 / NDFujianBIO-RAD (United States)100 / 97.55 / NDWANTAI (Beijing)99.5 / 98.5 / 0.03DalianInTec (Xiamen, China)100 / 98.6 / NDBIO-RAD (United States)100 / 97.55 / NDChangzhiBIO-RAD (United States)100 / 97.55 / NDInTec (Xiamen, China)100 / 98.6 / NDKaifengBIO-RAD (United States)100 / 97.55 / NDWANTAI (Beijing)99.5 / 98.5 / 0.03MianyangWANTAI (Beijing)99.5 / 98.5 / 0.03BIO-RAD (United States)100 / 97.55 / ND ND no data WANTAI Beijing WANTAI Biological Pharmacy Enterprise Co., Ltd. BIO-RAD BIO-RAD Clinical Diagnostics InTec Xiamen InTec Biological Pharmacy Enterprise Co., Ltd.