Adolescent girls are at high risk of acquiring sexually transmitted infections (STIs), including the human immunodeficiency virus (HIV). Global evidence indicates the significance of comprehensive sexual education in empowering adolescents with accurate knowledge regarding safe sexual practices. Adolescents living in rural areas, particularly, have inadequately developed life skills and limited health promotion knowledge and are at risk of being coerced into sexual relationships. The study aimed to assess the effect of peer group participation on improving knowledge about condoms among adolescent girls in rural eastern Ethiopia. The study analyzed data from a repeated cross-sectional study involving 3186 and 3290 adolescent girls during the baseline period (2016) and the endline period (2019), respectively. The respondents were adolescent girls aged 13–17 years old. The study’s outcome was knowledge about condoms, which was assessed using 3-item questions. A weighted multivariable logistic regression analysis was used to examine the effect of peer group participation on improving knowledge about condoms by controlling for potential confounders. Statistical significance was set at a p-value <0.05. The magnitude of good knowledge about condoms among peer-group participants was 23% higher in the endline compared to the baseline. The odds of having good knowledge about condoms among girls who participated in an organized peer group were 2.15 times higher than those who didn't participate (AOR: 2.15, 95% CI: 1.42, 3.26). Moreover, the odds of having good knowledge about condoms among those who reported high confidence in perceived communication skills were 1.68 times higher than those who reported no or little confidence (AOR: 1.68, 95% CI: 1.33, 2.13). Peer-group participation improved knowledge about condoms. Girls with high confidence in their perceived communication skills also had better knowledge about condoms. Peer-group education interventions have the potential to improve condom knowledge and thus improve sexual and reproductive health outcomes of adolescent girls. Further studies are needed in other contexts to inform intervention scale-up.

The authors have declared no competing interest.

The authors did not receive any funding for the authorship or the publication of this paper.

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The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

Institutional Review Board of Addis Continental Institute of Public Health (IRB registration/identification No. 0029).

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All data relevant to the study are included in the manuscript. The data can also be accessible upon request.