Evaluation of school-based iron supplementation adherence and determinant factors among adolescent girls in Indonesian settings

Background School-based iron supplementation is a key national intervention to reduce anaemia among adolescent girls, however evaluation regarding processes is lacking. This study evaluated adherence to iron supplementation and its determinant factors among schoolgirls in Indonesian settings. Methods A cross-sectional study was conducted at selected schools in priority areas of East Java ( n = 3) and Bali ( n = 4) from April-September 2023. A questionnaire administered to approximately 100 girls at each school collected data on the individual factors and adherence. School databases and interviews with 7 health unit staff was used to understand the environmental factors, and content analysis elicited the themes. Binary logistic regression summarised associations of individual and environmental factors contributing to adherence. Results A total of 694 girl respondents reported a mean adherence of 40%. Environmental themes included location (East Java/Bali), type and level of schools (private/public and Junior/Senior High School), iron tablet distribution and administration mechanisms (1-week supply/1-month supply/varied and weekly program at school/self-administered at home/no fixed program). Binary logistic regression confirmed that individual associations (i.e., attitude, Odds Ratio (OR) 2.69; peer support, OR 2.03), and environmental factors (i.e., type of school, OR 7.41; location, OR 2.38; administration mechanisms, OR 8.80) were independently associated with adherence. Conclusion Low adherence levels among schoolgirls reported in this study warrants attention. Identified contributing factors provide a basis for the development of strategies to improve adherence to school-based iron supplementation programs in Indonesian settings, particularly at priority areas.