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School-based Behaviour Change Intervention - 1.9 Times Lower Rate of Sexual Initiation


Strategy researched

A school-based intervention that sought to reduce sexual initiation and promote condom use through peer education, teacher-led lessons, and youth-friendly health service clinics

Impact achieved

For males, the incidence of sexual initiation in the intervention arm decreased from 11.5/100 person years at risk (PYAR) at month 6 to 7.3/100 PYAR at the 12-month follow up. For the control arm, the incidence of sexual initiation at 6 months was 13.2/100 PYAR and that at 12 months was 10.9/100 PYAR. The rate of sexual initiation at 12 months following the PREPARE intervention was almost 2 times higher among the control schools as compared to the intervention schools [adjusted relative risk (ARR) = 1.9, p = 0.027]. Similarly, females from the control arm were 1.6 times more likely to initiate sex as compared to those from the intervention arm. The intervention also positively influenced action planning to use condoms for both sexes, with a significantly higher level of action planning to use condoms reported among female adolescents in the intervention arm than those in the control arm (p = 0.042). An effect on condom use behaviour was observed among male adolescents (p = 0.004), but not among female adolescents (p = 0.463).

Country of study


Research methodology

Cluster RCT with 5,091 adolescents


BMC Public Health; 2017

Journal paper title and link

Effect of the PREPARE intervention on sexual initiation and condom use among adolescents aged 12-14: a cluster randomised controlled trial in Dar es Salaam, Tanzania

Excerpt from Abstract

"The PREPARE intervention had an effect in delaying self-reported sexual initiation among adolescents aged 12-14 in Dar es Salaam Tanzania. The intervention positively influenced action planning to use condoms for both sexes and increased actual condom use among male adolescents only."

Summary at this link


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The impact data presented meets the following high standard for inclusion criteria:

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  • Published since 2010.