Among young persons, declining condom use trends in many countries, high prevalences of chlamydia, and recent increases in gonorrhea diagnoses highlight the need to promote condom use. Individual social-cognitive factors and those of partners are known to influence condom use decision-making in steady partnerships, whereas research on casual partnerships is lacking. Our vignette study examined the influence of partner characteristics on condom use decision-making during casual vaginal sex. Dutch young people aged 16–24 (n = 1070) were recruited online in 2023. Participants indicated the likelihood of using a condom ('If I were in this situation, I would use a condom') after reading one of six randomly assigned partner vignettes. The last sentence of each vignette indicated the partner characteristics. The different partner characteristics in the vignettes were attitudes (positive/negative), norms (condom use/condom nonuse), and risk behavior (higher risk/lower risk). We performed three ANOVA analyses with Benjamini-Hochberg corrections; the dependent variable was the participant's condom use decision, the three manipulated constructs were categorical between-participant independent variables. We explored interactions between the conditions and participant characteristics (i.e., demographic, social-cognitive and sexual behavior). Participants were on average 19 years old, 55% was assigned female at birth. Participants were more likely to use a condom if the fictitious partner; had positive attitudes ηp²=0.17; indicated positive condom use norms ηp²=0.01; or engaged in more risk behavior ηp²=0.02. Different sexual behavior- and social-cognitive factors moderated these effects, e.g. condition effects were stronger in persons with more lifetime sexual partners or negative attitudes towards condom use. For example, participants who had more positive affective associations with condom use were less affected by a partner's negative attitudes toward condom use. Findings demonstrate that new, casual partners can influence condom use decision-making in young people, especially the partner's attitudes may be of importance. Our findings suggest that individuals go along with their partner's attitudes or norms, and may be more inclined to use a condom based on higher risk behavior of the partner. Considering a partner's influence and promoting positive attitudes towards condom use, specifically, but also promoting positive condom use norms may positively impact condom use.
Vries et al. (2025) studied this question.