Predictors of adherent use of diaphragms and microbicide gel in a four-arm, randomized pilot study among female sex workers in Madagascar.

Background: Participants' protocol adherence may influence assessments of the effectiveness of new female-controlled methods for sexually transmitted infection prevention.

Methods: In 2005 we conducted a randomized pilot study among female sex workers (FSWs) in Madagascar in preparation for sexually transmitted infection prevention trial of diaphragms and a vaginal microbicide. Participants (n = 192) were randomized into 4 arms: diaphragm plus microbicide (Acidform), diaphragm plus placebo gel hydroxyethyl cellulose (HEC), Acidform alone, or HEC alone.