Are out-of-school adolescents at higher risk of adverse health outcomes? Evidence from 9 diverse settings in sub-Saharan Africa

We analysed mutually comparable surveys on adolescent attitudes and behaviours from nine sites in seven sub-Saharan African countries, to determine the relationship between school enrolment and adolescent health outcomes.; Data from the Africa Research, Implementation Science, and Education Network cross-sectional adolescent health surveys were used to examine the associations of current school enrolment, self-reported general health and four major adolescent health domains: (i) sexual and reproductive health; (ii) nutrition and non-communicable diseases; (iii) mental health, violence and injury; and (iv) healthcare utilisation. We used multivariable Poisson regression models to calculate relative risk ratios with 95% confidence intervals (CI), controlling for demographic and socio-economic characteristics. We assessed heterogeneity by gender and study site.; Across 7829 adolescents aged 10-19, 70.5% were in school at the time of interview. In-school adolescents were 14.3% more likely (95% CI: 6-22) to report that their life is going well; 51.2% less likely (95% CI: 45-67) to report ever having had sexual intercourse; 32.6% more likely (95% CI: 9-61) to report unmet need for health care; and 30.1% less likely (95% CI: 15-43) to report having visited a traditional healer. School enrolment was not significantly associated with malnutrition, low mood, violence or injury. Substantial heterogeneity was identified between genders for sexual and reproductive health, and in-school adolescents were particularly less likely to report adverse health outcomes in settings with high average school enrolment.; School enrolment is strongly associated with sexual and reproductive health and healthcare utilisation outcomes across nine sites in sub-Saharan Africa. Keeping adolescents in school may improve key health outcomes, something that can be explored through future longitudinal, mixed-methods, and (quasi-)experimental studies.