Fig. 3: Prediction of female sex in NAPLS-3 and CAPR.
(***p < 0.001) A Probabilities of female sex based on the logistic regression model as a function of actual age, recruitment source, and sample. Lines represent the relationship between age and probability of female sex adjusted for recruitment source and sample. Panel A displays findings for self-referred online sources (left), self-referred not-online sources (middle), and other-referred sources (right). The main effect of age on sex (older age associated with a lower odds of female sex) (OR = 0.93, 95% CI = 0.89, 0.96) was significant, an effect illustrated in (A) by the similar regression line slopes across all groups. The proportion of females differed across studies only in the other-referred groups, as shown by the separation between lines in the panel showing other-referred sources. B Proportion of females varied by recruitment source and sample. Simple main effects analysis of the sample within recruitment source revealed that a higher proportion of females in CAPR vs NAPLS-3 was present only within the other-referred group, in which NAPLS-3 was 42.5% female and CAPR was 72.5% (Fig. 3B; χ2 (1) = 13.61, p < 0.001). Simple main effects of recruitment source within sample revealed that within NAPLS-3, participants recruited from other-referred sources were less likely to be female compared to self-referrals (Fig. 3B; χ2 (2) = 15.77, p < 0.001), including whether internet-based (Wald = 13.84, p < 0.001, OR = 3.36, 95% CI = 1.78, 6.37) or not-internet-based self-referrals (Wald = 15.59, p < 0.001, OR = 2.94, 95% CI = 1.72, 5.01). However, in the CAPR sample, the effects of recruitment source were not significant (ps > 0.05), where the proportions of females were greater than 50% for each of the three referral sources.
