A two-year risk-reduction program consisting of an intensive curriculum and a broad range of schoolwide activities significantly--and favorably--affected condom use among ninth and 10th graders in California and Texas. According to an analysis of 31-month follow-up data on 3,058 students from a randomized, controlled trial,¹ enrollment in the intervention significantly reduced both the number of times that students had unprotected sex and the number of partners they had unprotected intercourse with. Moreover, students exposed to the program were significantly more likely than those enrolled in a traditional program to have been protected from pregnancy the last time they had sex. Even though exposure to the intervention did not influence sexually inexperienced students to delay the initiation of intercourse, it resulted in several favorable psychosocial outcomes, including significantly improving students' knowledge scores about HIV and other sexually transmitted diseases (STDs), strengthening their belief in their ability to use a condom, enhancing their perception of their risk for HIV and lowering their perceived barriers to condom use.

The data come from a population-based study involving students in 20 public high schools in urban areas--10 schools in California and 10 in Texas. Five schools in each state were randomly assigned to the intervention and five to a comparison, knowledge-based program. Self-reported baseline data were collected in the fall of 1993, immediately before students started the theory-based risk-reduction program known as Safer Choices. The program consists of the following five components: a health promotion council (made up of teachers, students, parents, administrators and community representatives) to plan and conduct activities; a 20-lesson curriculum (i.e., 10 lessons at each grade level) with staff training for grades nine and 10; a peer team or club at every school to host activities designed to change normative behaviors; activities and resources for parents, including a project newsletter, health information and tips about communicating with their children; and activities to help students become familiar with support services and resources outside of their school.

Follow-up surveys were fielded at three points--seven months after the program began (i.e., immediately after the first year), 19 months after baseline (just after the second year) and 31 months after the start date (12 months following completion of the program). The outcomes assessed include a range of sexual risk behaviors, as well as students' scores on 13 psychosocial scales. The investigators created linear and logistic multilevel models--which took into account variables measured at baseline and at each follow-up survey--to test the intervention's overall effects over 31 months. The estimated effects are expressed as ratios of adjusted means, odds ratios or group coefficients.

Baseline data were collected from 3,869 students (1,983 intervention students and 1,886 control students). These data indicate that sizable proportions in each group were sexually experienced (31% of the intervention group and 26% of controls). Among these students, a majority had used a condom at last intercourse (61% and 56%, respectively). Seventy-nine percent of the original cohort completed the 31-month follow-up; thus, the final sample for analysis included 3,058 students.

The linear and multilevel logistic results show that the intervention had a favorable and significant impact on two of the three primary sexual behavior outcomes examined: Compared with sexually experienced students enrolled in a standard HIV prevention curriculum, those in Safer Choices had had unprotected sex fewer times in the three months preceding the final follow-up (ratio of adjusted means, 0.6), and they had had unprotected sex with fewer partners in that time period (ratio of adjusted means, 0.7). There was no significant difference by exposure to the program, however, in the proportion of students who had initiated intercourse.

Compared with students in a traditional HIV prevention curriculum, those enrolled in Safer Choices had significantly higher odds of having used a condom at last intercourse (odds ratio, 1.7) and of having been effectively protected against pregnancy by using the pill, the condom or both at last intercourse (1.8). Exposure to the intervention had no significant independent effect on the six remaining secondary outcomes: condom use at first intercourse (among those initiating activity after the intervention began); frequency of intercourse in the past three months; number of recent sexual partners; alcohol or drug use before recent sexual activity; and the likelihood of being tested for HIV or of being tested for other STDs.

The intervention significantly improved students' performance on seven of the 13 psychosocial measures. At the 31-month follow-up, students exposed to Safer Choices scored significantly higher than those in the comparison program on scales measuring their knowledge of HIV and other STDs, they also held more positive attitudes toward condoms, and believed more strongly in their ability to use a condom, reported higher levels of perceived personal risk for HIV and for other STDs, and faced fewer barriers to condom use. (Adjusted mean differences between groups ranged from seven to 11 percentage points.) Exposure to the curriculum had a marginally significant impact on perceptions of peer norms regarding condom use and on students' communication with their parents. Enrollment in Safer Choices had no independent effect, however, on attitudes and normative beliefs toward sexual intercourse, and on students' beliefs in their ability to refuse sex or to communicate with a partner about sexual limits.

The intervention's impact was relatively consistent over the 31-month follow-up period; the results of an analysis testing for an interaction between the assigned group and time suggest that the magnitude of the effects diminished only somewhat, and not significantly, over time. Furthermore, most of the behavioral effects that proved to be significant at the 31-month follow-up were also significant when measured at one or both of the two earlier follow-up surveys, while the curriculum's significant effects on students' psychosocial measures at the final follow-up were consistently significant throughout.

The authors observe that overall, Safer Choices had a greater impact on condom-use outcomes than on outcomes related to delaying sex, despite the program's extensive emphasis on students' choosing not to have sex as the "safest" choice for reducing the risk of pregnancy and of HIV and other STDs. They assert that more research is needed to successfully identify approaches that would delay sexual initiation and improve students' beliefs in their ability to refuse intercourse and to communicate about sexual limits. Nonetheless, because the study succeeded in improving four out of five condom-use outcomes, and seven out of 13 psychosocial variables, the investigators conclude that "theory-driven, school-based, multi-component programs with a clear message can enhance psychosocial variables and reduce sexual risk behaviors."--L. Remez

REFERENCE

1. Coyle K et al., Safer Choices: reducing teen pregnancy, HIV, and STDs, Public Health Reports, 2001, 116 (Suppl.):83-93.