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Sex and HIV Education Programs: Their Impact on Sexual Behaviors of Young People throughout the World
Global Health Sciences Literature Digest
Published May 9, 2007
Journal Article

Kirby DB, Laris BA, Rolleri LA. Sex and HIV Education Programs: Their Impact on Sexual Behaviors of Young People throughout the World. J Adolesc Health. 2007 Mar;40(3):206-17.


To conduct a systematic review of worldwide studies of youth to: a. determine the impact of curriculum-based sex- and HIV-education programs on sexual risk behaviors, STDs, and pregnancy rates, and on mediating factors such as knowledge and attitudes; b. identify characteristics of those curriculum-based programs that were effective in changing sexual risk behaviors.

Study Design

Ten databases (PubMed, PsycINFO, Popline, Sociological Abstracts, Psychological Abstracts, Bireme, Dissertation Abstracts, ERIC, CHID, and Biologic Abstracts) were searched to identify studies published since 1990 meeting inclusion criteria. Relevant studies were also identified by reviewing past issues of selected journals; directly contacting researchers; reviewing reports, training materials, and process evaluations; and evaluating previous reviews. To be included, studies had to meet both program and research methods criteria. Studies conducted anywhere in the world were included. Programs had to be curriculum- or group-based, provide sex or HIV eduction, and focus on adolescents or young adults ages 9 to 24 years. Research methodology had to: 1. include an experimental or quasi-experimental design with both intervention and comparions groups and pre- and post-test data; 2. have a sample size of at least 100 persons; 3. measure program impact upon one or more of the outcomes listed below; and 4. measure impact on behaviors that can change quickly (e.g. frequency of unprotected sex) over at least a three-month period, or measure impact on behaviors that change less quickly (e.g. initiation of sex) for at least a six-month period.


A total of 83 studies were included. (The number initially identified through the search strategy was not mentioned). Fifty-six studies were conducted in the US, nine in other developed countries (Canada, Netherlands, Norway, Spain, and the U.K.) and eighteen (22%) in developing countries (Belize, Brazil, Chile, Jamaica, Kenya, Mexico, Nigeria, South Africa, Tanzania, Thailand, and Zambia). Half (51%) of the studies employed an experimental design with random assignment of individuals or clusters. The remaining half used a quasi-experiemental design. About 88% of the studies used a matched-cohort design linking baseline and follow-up survey data; the remainder used pre- and post-cross-sectional surveys.


All studies targeted adolescents or young adults aged 9-24 years old. Data on the numbers and characteristics of participants were not provided.


Of the 83 studies, 52% focused only on STD/HIV prevention, 17% only on pregnancy prevention, and 31% on both. Nearly all (90%) included at least two different interactive activities. At least 90% of programs trained curriculum educators. The mean length of the programs was 12 hours (range: <1 hour to 48 hours). Just over half (59%) measured impact over a year or more; 22% measured impact over two years or more.

Outcome Measures

Primary outcomes were one or more of the following sexual behaviors: age of sexual initiation, frequency of sex, number of sexual partners, condom use, contraceptive use, and composite measures of sexual risk-taking. Measures of sexual and contraceptive behavior relied on self-reports. A few studies reported pregnancy and STD rates; however, only 4 of 13 studies measuring pregnancy and 5 of 10 studies measuring STD acquisition used laboratory testing; the others relied on self-report.


Age of sexual initiation: 22 of 52 studies (42%) measuring this outcome found a delay in sexual initiation by at least six months, 29/ 52 (55%) found no significant impact, and 1 found earlier sexual initiation. Frequency of sex: 9 of 31 studies (29%) found a reduction in sexual frequency, 19 of 31 (61%) found no change, and 3 found an increased frequency. Number of sexual partners: 12 of 34 studies (35%) found a decrease in numbers of partners, 21 of 34 (62%) found no significant impact, and 1 found a negative impact. Condom use: 26 (48%) of 54 studies identified an increase in condom use with programs; none were associated with decreased condom use. Contraceptive use: 6 of 15 studies (40%) showed increased contraceptive use, 8 (53%) showed no impact, and 1 showed a decrease. Sexual risk-taking: 14 of 28 studies (50%) found a reduction in sexual risk-taking; none found increased sexual risk-taking. Pregnancy rates: 3 of 13 studies (23%) found a significant reduction in pregnancy rates, 9 (69%) found no change, and 1 found increased pregnancy rates. STD rates: 2 of 10 studies (20%) found a reduction in STD rates, 6 (60%) found no significant impact, and 2 found an increase.

Characteristics of effective curricula: An in-depth analysis of effective programs identified the following 17 common characteristics. Curriculum development: 1. involved multiple people with different backgrounds; 2. assessed needs of the target group; 3. used a logic-model approach; 4. designed activities consistent with community values and available resources; 5. pilot-tested the program. Curriculum content:6. focused on clear health goals; 7. focused narrowly on specific behaviors leading to those health goals, gave clear messages, and addressed situations that might lead to those behaviors and how to avoid them; 8. addressed multiple sexual psychosocial risk and protective factors affecting sexual behaviors; 9. created a safe social environment for youth; 10. included multiple activities; 11. employed instructionally sound teaching methods that involved the participants; 12. employed activities, instructional methods, and behavioral messages that were appropriate to the youth culture, developmental age, and sexual experience; 13. covered topics in a logical sequence. Curriculum implementation:14. secured at least minimal support from appropriate authorities; 15. carefully selected educators, trained them, and provided monitoring, supervision and support; 16. if needed, implemented activities to recruit and retain youth; 17. implemented virtually all activities with reasonable fidelity.


The authors concluded that there is evidence for a positive impact of curriculum- and group-based sex and HIV education programs on behavior for adolescents and young adults. The patterns of findings were similar in both developed and developing countries, and programs were effective with both low- and middle-income and rural and urban youth, among girls and boys of different ages, and in different settings (school, clinic, community). Consistently, skill-based programs were more effective at changing behavior than were knowledge-based programs.

Quality Rating

Based on the QUOROM grading system for systematic reviews, this review was of high quality. The search was comprehensive. There were some weaknesses in the studies themselves--few adequately described their respective programs, and none were programs for youth engaging in same-sex behaviors. A few studies had relatively weak quasi-experimental designs; an unknown number had measurement problems; many were statistically under-powered; and only a few adjusted for multiple tests of significance. A comparatively small proportion included hard outcomes such as pregnancies or STDs, and among these, many relied on self-report rather than biological tests. There are inherent publication biases, as journals and researchers are more likely to publish articles reporting positive results.

In Context

Sex and HIV/STD education programs that are based on a written curriculum and that are implemented among groups of youth in school, clinic, or community settings may help to reduce adolescent sexual risk behaviors. It should be noted that for each outcome measured, about half of all programs resulted in no significant change.

There have been many previous reviews of the impact of sex and HIV education programs on behavior, but they typically have been limited to a particular geographical area,(1,2,3) are out-of-date,(4) or do not analyze the characteristics of effective programs. This review attempted to overcome some of these limitations.

Programmatic Implications

There is evidence that strong curriculum- and group-based sex and HIV education programs for adolescents and young adults can have an impact on lowering risk behaviors. Just as importantly, however, there is no evidence to suggest that such programs increase sexual behavior, as some have feared. This concern has been used as a reason not to provide sexual-prevention information to youth. However, programs targeting youth should be an important component of overall prevention strategies. The majority of studies evaluated here were not among resource-poor settings. The development and evaluation of strong adolescent and young-adult interventions are needed, particularly in sub-Saharan Africa, where teen pregnancy rates are high and adolescent girls are becoming HIV-infected. Educational programs need to be coupled with youth-friendly services providing access to STD treatment, condoms, family planning, counseling, and HIV testing. Prevention is most successful when treatment and services are also available.


  1. Kirby D. Emerging answers: Research findings on programs to reduce teen pregnancy. Washington DC: The National Campaign to Prevent Teen Pregnancy, 2001. (Available at
  2. Mullen PD, Ramirez G, Strouse D, Hedges LV, Sogolow E. Meta-analysis of the effects of behavioral HIV prevention interventions on the sexual risk behavior of sexually experienced adolescents in controlled studies in the United States. J Acquir Immune Defic Syndr 2002 Jul 1;30 Suppl 1:S94-S105.
  3. Gallant M, Maticka-Tyndale E. School-based HIV prevention programmes for African youth. Soc Sci Med 2004 Apr;58(7):1337-51. Review.
  4. FOCUS on Young Adults, Advancing Young Adult Reproductive Health: Actions for the Next Decade. Washington DC: Pathfinder, 2001. (Available at