The researchers conducted telephone interviews with a representative sample of male residents of New York City. Among 130 survey items, participants were asked several questions about whether they considered themselves straight or bisexual. A section of the interview separated from the questions on self-identification of sexual orientation contained other questions about the participants' actual sexual practices and whether they had sex only with women, only with men, or with both men and women. In addition, participants were asked questions about whether they had undergone HIV testing, their use of condoms, and whether they had a history of sexually transmitted disease.