Title: Reborn a virgin
Description: Adolescents engage in many risky behaviors, such as smoking, substance use, and unprotected sexual activity, which jeopardize their current and future health. Adolescents may not report their risk behaviors accurately. The first chapter examines inconsistent reporting of sex and virginity pledge histories in a one year time-frame in the National Longitudinal Study of Adolescent Health (Add Health, n=13,568). More than half of wave 1 virginity pledgers denied at wave 2 having made a pledge; pledgers who initiated sexual activity were 3 times as likely to deny having made a pledge (odds ratio [OR]=3.21; 95% confidence interval [CI] = 2.04, 5.04). Among wave 1 nonvirgins who subsequently took virginity pledges, 28% retracted their sexual histories at wave 2; respondents who took virginity pledges were almost 4 times as likely as those who did not to retract reports of sexual experience (OR=3.88; 95% CI=1.87, 8.07). The second chapter examines 72 risk behaviors in a reliability study of the Youth Risk Behavior Survey (n=4619) administered at an interval of 2 weeks. It finds that adolescents report their sex and substance use most consistently, and weight control efforts least consistently, possibly due to the different salience of these activities for adolescents.

The third chapter examines whether the sexual behavior and birth control use of virginity pledgers differs from that of non-pledgers. Prior studies use parametric methods which may not adequately adjust for pre-pledge differences between pledgers and non-pledgers. This paper uses exact and nearest-neighbor caliper matching to create a control group of non-pledgers (n=645) comparable to pledgers (n=289) matched on over 100 pre-pledge factors. Five years post-pledge, 84% of pledgers denied having ever pledged. Pledgers and matched non-pledgers did not differ in premarital sex, STDs, anal, and oral sex. Pledgers had 0.1 fewer past year partners but the same number of lifetime sexual partners and age of first sex. Fewer pledgers than matched non-pledgers used birth control and condoms in the past year, and birth control at last sex.