Knox J, et al. - In the current study, researchers examined how psychosocial factors influence the relationship between substance use and sexual risk behavior. They conducted a cross-sectional survey among 480 black South African men who have sex with men, enquiring about the last sexual event that involved anal sex. Findings revealed no correlation of substance use with unprotected anal intercourse (UAI). Safer sex intentions were identified as modifying the effect of substance use on UAI. They noted the positive association of substance use with UAI among those with higher safer sex intentions. Findings revealed the association of substance use with increased risky sexual behavior among men who have sex with men with high intentions to engage in safer sex.gage in safer sex.