Evaluation of the service quality and diagnostic performance of syphilis self-test kits purchased from E-commerce platforms in China

Syphilis self-testing (SST) facilitates screening accessibility among key populations (such as men who have sex with men, female sex workers, etc.). SST kits are readily available on several prominent e-commerce platforms in China. This study aims to compare the differences of diagnostic performance between kits obtained online or based on facilities, which provided evidence for the expanding application of SST in China. Utilizing the HONcode standard, we developed a quality assessment scale to evaluate the service quality of online SST kits. Furthermore, we assessed the diagnostic performance of them compared with facility-based kits, using TPPA as the gold standard. The online sales data showed that the after-sales reviews for SST kits accounted for only 5.5% of HIV self-testing kits and 17% of HIV/syphilis dual-testing kits. Quality assessment results indicated scale scores ranging from 31 to 44 for these SST kits, reflecting satisfactory service quality. The sensitivity and specificity of eight online kits were 94.85%-100% and 98.90%-100%, respectively, and the nine facility-based testing kits were 91.91%-100% and 97.81%-100%, respectively. The online SST kits demonstrated satisfactory quality and diagnostic performance, which provide evidence for promoting the utilization among key populations in China.