Condom use to prevent incident STDs: the validity of self-reported condom use

Background: Studies of sexual behavior and of interventions designed to reduce human immunodeficiency virus risk usually depend on self-report. Validation of self-reported condom use measures has not been previously reported in an urban population at high risk for sexually transmitted diseases and human immunodeficiency virus. Methods: A prospective cohort study was performed in subjects recruited from sexually transmitted disease clinics in Baltimore. At enrollment, a questionnaire was administered that assessed human immunodeficiency virus risk factors and sexually transmitted disease history, and used a retrospective calendar to assess sexual events and condom use over the previous 30 days. Clinical evaluation was performed for sexually transmitted diseases. At follow-up 3 months later, the same procedures were repeated. Incident sexually transmitted diseases at follow-up were defined as new culture or serologically documented diagnoses of gonorrhea, chlamydia, syphilis, or trichomoniasis. Results: In the 323 male and 275 female (total = 598) subjects who completed a follow-up visit, 21% reported using condoms for every act of sexual intercourse over the previous 30 days, 21% reported occasionally using condoms, and 59% reported not using condoms. At follow-up, 21% of subjects had new incident gonorrhea, chlamydia, syphilis, or trichomoniasis. Fifteen percent of the men who were 'always' condom users had incident sexually transmitted diseases compared with 15.3% of 'never users;' 23.5% of women who were 'always' users had incident sexually transmitted diseases compared with 26.8% of 'never' users. Conclusions: In this high-risk population, self-reported condom use is not associated with lower sexually transmitted disease incidence. This finding suggests that selfreported condom use measures, even in a research setting, may be subject to substantial reporting bias.
Self-reported use of condoms may not be a reliable measure of condom use among populations at high risk for sexually transmitted diseases (STDs). A group of 323 men and 275 women attending STD clinics in Baltimore were interviewed about their sexual habits and STD history. All participants were examined and treated for gonorrhea, chlamydia, syphilis, or trichomoniasis, if present and given an appointment for a follow-up visit. Three months later, the interview and examination were repeated. Among the men who reported using condoms for every act of intercourse, the incidence of new infection was 15% compared with 15.3% of men who reported never using condoms. Among women who reported using condoms for every act of intercourse, 23.5% had a new infection versus 26.8% who reported that they never used condoms. Since condoms protect against STDs, this strongly suggests inaccurate reporting.