Pre-exposure prophylaxis knowledge as a mediator between eligibility and intention to use among voluntary counselling and testing clients, Thailand.

Thailand has made notable progress in HIV prevention, yet challenges persist, particularly among high-risk groups. Pre-exposure prophylaxis (PrEP) is a proven biomedical strategy to prevent HIV, but its uptake remains below national targets. This study examined whether PrEP knowledge mediates the relationship between PrEP-eligible behaviors and intention to use PrEP among clients accessing voluntary counseling and testing (VCT) services at government health facilities in Thailand. A cross-sectional, web-based survey was conducted between October 2024 and March 2025. A two-stage sampling approach was used to select 62 public hospitals across country. There were 2,007 eligible VCT clients voluntarily participated the study. Mediation analysis was performed using the SPSS PROCESS macro. Results showed that PrEP-eligible behaviors significantly predicted both PrEP knowledge (β = 0.42, p < 0.001) and intention to use PrEP (β = 0.38, p < 0.001). PrEP knowledge was also positively associated with intention to use PrEP (β = 0.47, p < 0.001) and partially mediated the relationship between eligibility and intention (indirect effect = 0.20, 95% CI [0.15, 0.26]). These findings underscore the importance of enhancing PrEP knowledge to drive preventive behavior. Targeted educational strategies and improved integration of PrEP services into public health infrastructure are essential to expand uptake and meet Thailand's goal of eliminating AIDS as a public health threat by 2030.