Sexually Unexperienced Adolescents Benefit the Most From a Sexual Education Program for Adolescents: A Longitudinal Cluster Randomized Controlled Study

Using a longitudinal cluster-randomized controlled design, we examined whether the effects of Competencies for Adolescents with a Healthy Sexuality (COMPAS), an evidence-based sexual health promotion intervention, differ by adolescents’ sexual experience. Participants were 699 students aged 14–16, 45.9% were sexually experienced, and assessed in the baseline, posttest, and 12- and 24-month follow-ups. All were recruited from 10 schools that were randomly assigned to the COMPAS program and waiting-list groups (WLG). Using an intent-to-treat analyses, longitudinal changes in psychosocial and behavioral outcomes were explored using generalized estimating equations. Compared to the WLG, COMPAS had a positive impact on six of the seven psychological and behavioral outcomes. Non-sexually experienced reported more favorable HIV-related attitudes, higher condom use intention, lower number of sexual partners, and higher condom use than those sexually experienced. Findings support the importance of implementing sex education actions before adolescents get involved in their first intimate relationships in order to achieve greater impact.