It is a primary topic inside benefit two grounds: first, self-selection of members considering what their age is is especially visible in gay surveys: participating in eg surveys involves to invest in a good gay log otherwise expenses time in the gay websites, and you may reacting questions regarding sexual behaviors
Furthermore, convenience testing tips are recognized to lead to involvement prejudice regarding many years [38, 39]. This point try portrayed because of the discovering that the fresh new youngest people (18–24) enrolled in the fresh studies had a median age initially intercourse with a guy below that of older users. We would together with suppose earlier MSM who proceeded to become listed on in the studies was in fact the quintessential working in sexuality and/or purchased gay life. The second is that people conducted a get older-age group data, which experience with age feeling is essential for interpreting the sexual trajectories of your own consecutive years out-of MSM. Appropriately, we made use of bi- and you will multivariate models you to definitely welcome us to to alter to have ages in the introduction to many other possible confounding situations, particularly instructional peak, sized city of residence, self-discussed sexual direction and supply of new questionnaire.