Efficacy of a Telephone-Delivered Sexually Transmitted Infection/Human Immunodeficiency Virus Prevention Maintenance Intervention for Adolescents

IMPORTANCE: Behavioral change interventions have demonstrated short-term efficacy in reducing sexually transmitted infection (STI)/human immunodeficiency virus (HIV) risk behaviors; however, few have demonstrated long-term efficacy. OBJECTIVE: To evaluate the efficacy of a telephone counseling prevention maintenance intervention (PMI) to sustain STI/HIV-preventive behaviors and reduce incident STIs during a 36-month follow-up. DESIGN, SETTING, AND PARTICIPANTS: In a 2-arm randomized supplemental treatment trial at 3 clinics serving predominantly minority adolescents in Atlanta, Georgia, 701 African American adolescent girls aged 14 to 20 years received a primary treatment and subsequently received a different (supplemental) treatment (PMI) to enhance effects of the primary treatment. INTERVENTIONS: Participants in the experimental condition (n = 342) received an adapted evidence-based STI/HIV intervention (HORIZONS) and a PMI consisting of brief telephone contacts every 8 weeks over 36 months to reinforce and complement prevention messages. Comparison-condition participants (n = 359) received HORIZONS and a time- and dose-consistent PMI focused on general health. MAIN OUTCOMES AND MEASURES: The primary outcomes were percentage of participants with a laboratory-confirmed incident chlamydial infection and percentage of participants with a laboratory-confirmed gonococcal infection during the 36-month follow-up. Behavioral outcomes included the following: (1) proportion of condom-protected sexual acts in the 6 months and 90 days prior to assessments; (2) number of sexual episodes during the past 90 days in which participants engaged in sexual intercourse while high on drugs and/or alcohol; and (3) number of vaginal sex partners in the 6 months prior to assessments. RESULTS: During the 36-month follow-up, fewer participants in the experimental condition than in the comparison condition had incident chlamydial infections (94 vs 104 participants, respectively; risk ratio = 0.50; 95% CI, 0.28 to 0.88; P = .02) and gonococcal infections (48 vs 54 participants, respectively; risk ratio = 0.40; 95% CI, 0.15 to 1.02; P = .06). Participants completing more telephone contacts had a lower risk of chlamydial infection (risk ratio = 0.95; 95% CI, 0.90 to 1.00; P = .05). Participants in the experimental condition reported a higher proportion of condom-protected sexual acts in the 90 days (mean difference = 0.08; 95% CI, 0.06 to 0.11; P = .02) and 6 months (mean difference = 0.08; 95% CI, 0.06 to 0.10; P = .04) prior to assessments and fewer episodes of sexual acts while high on drugs and/or alcohol (mean difference = -0.61; 95% CI, -0.98 to -0.24; P < .001). CONCLUSIONS AND RELEVANCE: Sustaining the long-term impact of an STI/HIV intervention is achievable with brief, tailored telephone counseling. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00279799.