STDs present a preventable and continuing public health issue. Certain behaviors can increase the risk of STDs among young people. Additionally, much of the data used depends on potentially unreliable self-reported information. This dissertation (1) examined life-time risk factors and trajectories for STDs, (2) illuminated sexual health behaviors associated with HAI, and (3) investigated the validity of using a popular SDS in a young, urban population.

The first study investigated the longitudinal effects of broader, individual, and partnership factors on number of sex partners and concurrent sexual relationships. Broader influences such as lesser degrees of parental support and being a native English speaker or having higher levels of acculturation suggest increases in both number of sexual partners and the occurrence of concurrent sexual relationships. We also found that substance use, including alcohol use, was associated with higher numbers of sexual partners and likelihood of concurrent sexual relationships. Finally, we found that the trajectories of sexual partners were not only explained by time, but by demographic characteristics.

The second study used individual- and partner-level analyses to assess the association of demographic and behavioral characteristics with HAI. Demographic factors, such as identifying as Black/African American, or behaviors, such as alcohol consumption and having a sexual partner who was recently incarcerated, were associated with more reporting of HAI. Additionally, HAI was more likely to occur in main, longer, and more committed partnerships, as well as relationships where IPV was present.

The third study evaluated the validity of using an older, popular SDS in a young, urban population. Factor analyses identified 15 questions from the MC-SDS that worked well in our population and differ from other short form versions. Of these 15 items, 20% were determined to be harder to answer based on underlying SD and about half were better able to differentiate between question scores for average SD. Finally, older age groups provided more socially desirable answers.

The findings from this dissertation help highlight characteristics and behaviors that can be incorporated into sexual health interventions to reduce STDs, and to improve how we collect and analyze data related to reported sexual health behaviors.