Teaching teens about sexually transmitted infections at school boosts factual knowledge, but does not necessarily translate to increased condom use, according to a new review from the United Kingdom.
"The school-based programs that provide information and teach young people sexual health negotiation skills that were included in our review had limited effects on young people," said lead author Jonathan Shepherd, Ph.D. "In nearly all cases they helped young people improve their knowledge about the transmission and prevention of sexually transmitted infections. However, the effects of the studies on other outcomes were mixed."
Shepherd is a principal research fellow at the Southampton Health Technology Assessments Centre (SHTAC) at the University of Southampton, in England.
The U.S. Centers for Disease Control and Prevention (CDC) estimated that in the United States, about 1 million teens and young adults reported chlamydia, gonorrhea or syphilis infection in 2006. One quarter of 15- to 19-year-old U.S. girls reported human papillomavirus infection in 2003 to 2004.
In the review, which appears in the latest issue of Health Technology Assessment, researchers evaluated data from 12 studies of school-based sexually transmitted disease (STD) education programs.
The authors also analyzed three additional studies; however, these studies were ranked as less methodologically sound. Some review findings, like follow-up length, include all 15 studies, while others, like effective findings, take only the higher-quality studies into account.
All told, the studies comprised more than 30,000 teens between the ages of 13 and 19.
The studies, which included both peer-led and teacher-led programs, examined the programs' influence on when teens started sexual intercourse, their use of condoms, sexual intercourse rates, contraception and pregnancy rates and number of sexual partners. Twelve studies took place in the United States.
"Some, but not all, studies showed that they were able to help young people to increase their self-efficacy — their belief that they were able to successfully negotiate the use of condoms in sexual encounters — and also to strengthen their intentions to protect themselves when having sex," Shepherd said.
In addition, 10 of 12 studies showed that teen program participants knew more about how STDs were transmitted and prevented, compared to teens who did not participate.
However, when researchers analyzed the combined study results, the interventions' effect on specific sexual behaviors, such as using condoms for sex, remained unclear. "It cannot be concluded that the interventions encouraged or discouraged the use of condoms," Shepherd said.
Participation in STD education programs failed to influence the age at which teens started having sexual intercourse significantly, the reviewers reported. Three of the five studies that evaluated this outcome found no difference in age of first intercourse between the students who participated in the program and students who served as a comparison group.
On the other hand, participating in these programs did not increase teens' sexual activity or number of sexual partners, either.
"What we often worry about is that these interventions that talk about making good sexual decisions will lead to an increase in sexual behaviors, but they don't. That's an important thing to remember," said Susan Rosenthal, Ph.D., a pediatric psychologist at Morgan Stanley Children's Hospital at New York Presbyterian in New York City. She has no affiliation with the review.
"It's clear that we need to do something to help teenagers make good decisions," said Rosenthal, whose research focuses on prevention of sexually transmitted infections. "I think they looked at the right outcomes, but you have to look at how those outcomes transition over time."
The authors reported that 10 of the 15 studies followed participants for less than a year, which made it difficult to determine whether the programs had a lasting effect on teens' behavior.
"This is a sensitive area of health promotion and is challenging to evaluate, particularly to establish whether there is any long-term benefit," Shepherd said.
As part of the analysis, researchers also examined the overall cost-effectiveness of the programs. Most notably, they found that teacher-led interventions proved cheaper than peer-led programs, since teachers did not require yearly retraining.
Though this analysis pointed to mixed outcomes on sexual behaviors, Rosenthal said it would be misleading to suggest that STD prevention programs are not valuable.
"The key remains that every parent whose adolescent is in these interventions ought to know what the intervention is. The intervention should be fact-based, and not fear-based. Talking to kids about contraception and decision-making doesn't lead to an increase in risky behaviors. You want to keep the lines open and foster communication," Rosenthal said.
Shepherd J, et al. The effectiveness and cost-effectiveness of behavioural interventions for the prevention of sexually transmitted infections in young people aged 13-19: a systematic review and economic evaluation. Health Technology Assessment 2010; 14(00).
Health Technology Assessment