- Only 1 abstinence-only education program has been experimentally evaluated (Postponing Sexual Involvement/ENABL) and showed no impact on sexual activity. Few strong experimental evaluations of abstinence-only programs have been conducted. Future evaluations will assess the effectiveness of these programs.

- Only 1 experimental study has examined the impact of programs to increase parent-child communication about abstinence, sexuality, or HIV. This program showed no impact on the initiation of sexual intercourse (Facts and Feelings).

- 8 sexuality education programs measured sexual initiation as an outcome. Of these, 2 showed positive impacts for boys (Draw the Line/Respect the Line and Teen Talk), 1 showed positive impacts for girls (Postponing Sexual Involvement, Human Sexuality, and Health Screening ), 4 showed no impact (McMaster Teen Program;  Project SNAPP ;  Safer Choices; and Blake et al., 2000 in Michigan, Sexuality Education Programs), and 1 showed negative impacts for 9th and 10th graders, but no impacts for 8th graders (Health for Life Project ).

- Of the 5 HIV/AIDS education programs that measured sexual initiation as an outcome in experimental evaluations, 2 showed positive impacts (Becoming a Responsible Teen and Be Proud! Be Responsible! A Sexual Abstinence Curriculum ). Three programs showed no impacts (Be Proud, Be Responsible ;  Be Proud! Be Responsible! A Safer Sex Curriculum; and YAPP).

- One intensive long-term program that combines youth development and sexuality education delays sexual initiation among females but not males (CAS-Carrera).

- Reduce other risky behaviors such as substance abuse and delinquency.

- Focus on developing abstinence values among teens and encourage them to sign virginity pledges.

- Work with adolescents to change their perception that most peers are sexually active and that sexual experience elicits respect from peers.

- Improve educational performance. 

- Encourage teens to form high educational aspirations.

- Promote participation in sports (effective for girls only).

- Place importance on religious and moral beliefs.

- Promote church attendance/religiosity/religious activities.

- Having an older sibling who is sexually experienced is a risk factor for early sexual initiation.

- Promote stability in parents' marital status.

- Strengthen parent-child emotional bonds and relationships.

- Encourage parents to talk with their teens about sex and contraception; in particular, communicate disapproval of these behaviors.

- Advocate strong parental monitoring.

- Focus on ways to reduce "intergenerational transmission" of teenage sexual behaviors.

- Improve family economic standing and parent education.

- Live in a community with higher socioeconomic status and lower crime levels.

- Encourage teens to form friendships with peers who favor delayed sexual initiation and with same-age peers (as opposed to older teens), or change peer group values.

- Reduce the occurrence of non-voluntary sexual experiences.

- Delay teen involvement in romantic relationships.

- Sexuality education and HIV education programs that include 10 components were associated with more positive outcomes (Kirby, 2001).

- Sexuality or HIV education programs that did not include the 10 components listed above, including programs that were primarily didactic and that did not include teen involvement, were not associated with a reduced frequency of sexual activity. Programs short in duration appear to have no association with outcomes.