Determinants of alcohol consumption in HIV-uninfected injection drug users.

We assess the association between time fixed and time varying participant characteristics and subsequent alcohol consumption in 1968 injection drug users (median age 37 years, 28% female, 90% African-American) followed semi-annually from 1988 to 2008. Median alcohol consumption was seven drinks per week at study entry (first and third quartile: 1, 26) with 36% reporting binge drinking. Alcohol consumption and binge drinking decreased over follow-up.

Effects of time-varying exposures adjusting for time-varying confounders: the case of alcohol consumption and risk of incident human immunodeficiency virus infection.

Objective: Discuss issues related to time-varying exposures using as an example the recently meta-analyzed literature (Baliunas et al. in Int J Public Health, 2009) on alcohol consumption and risk of HIV infection.

Methods: Cataloged sources of bias and imprecision in the context of time-varying exposures.

Emergency contraceptive use as a marker of future risky sex, pregnancy, and sexually transmitted infection.

Objective: The objective of the study was to examine whether emergency contraceptive use predicts future sex at risk for pregnancy, pregnancy, or sexually transmitted infection among young women.

Study Design: A secondary analysis of control group participants (n = 718) from a recent trial of advanced provision of emergency contraception was conducted.

Results: We found no association between use of emergency contraception and either pregnancy or infection.