RESUMEN
Despite developmental differences between young adults and adults, studies of condom use have not typically considered young adults as a distinct age group. This study sought to examine how condom use and its correlates differed between high-risk young adults and adults. Sexually transmitted infection (STI) clinic patients (n = 763) reported STI history, contraception, negative condom attitudes, fear of partner reaction to condom use and risky behaviours. Past 3-month condom use was examined as unprotected vaginal sex (UVS) acts, proportional condom use and consistent condom use. Regression models tested associations of age group and potential correlates with each condom use outcome. Interaction models tested whether associations differed by age group. Proportional condom use was greater in young adults than adults (mean 0.55 vs. 0.47); UVS and consistent condom use were similar between age groups. Young adults with a recent STI reported less condom use, whereas for older adults, a distant STI was associated with less condom use, compared to others in their age groups. Negative condom attitudes were more strongly linked to UVS acts for younger versus older adults. STI prevention efforts for younger adults may be improved by intensifying counselling about condom use immediately following STI diagnosis and targeting negative condom attitudes.