Hazard Ratio of Incident HIV Infection (SAVVY versus Placebo) with and without Adjustment for Baseline Covariates in Effectiveness and Evaluable Populations.

aModel M1: treatment effect without adjustment for covariates.
bModel M2: treatment effect adjusted for site.
cModel M3: treatment effect adjusted for site and other baseline covariates, including ever been pregnant, previous experience using spermicides, number of different male partners, number of vaginal sex acts not protected by condoms, and positive GC or CT at baseline.
*Model that adjusted for site and baseline covariates was not implemented for Evaluable population due to small number of events.