Adult Humans 69 adult 69 human 69 male 59 female 57 Male 54 Female 53 psychology 49 Young Adult 34 young adult 34 Adolescent 26 HIV Infections 26 Human immunodeficiency virus infection 26 Middle Aged 26 adolescent 26 middle aged 26 major clinical study 19 article 18 Sexual Behavior 16 sexual behavior 16 statistics and numerical data 16 Human immunodeficiency virus 14 nonhuman 14 Article 13 Homosexuality, Male 13 male homosexuality 13 HIV 12 questionnaire 12 sexuality 12