Understanding factors associated with under-five mortality rate in Indonesia: findings from an ecological study across 34 provinces

Background: This study examined the population-level factors associated with the under-five mortality rate (U5MR) across 34 provinces in Indonesia using an ecological study design. Methods: U5MR data were obtained from BPS-Statistics Indonesia. Demographic, healthcare, and fertility-related factors were included as independent variables. An ecological study design was applied, with 34 provinces serving as the units of analysis. Hierarchical Poisson regression was used to assess the associations between the variables. All variables were log-transformed prior to the analysis. Results: The U5MR in 2020 was 19.83 per 1,000 live births. Fertility and demographic factors were significantly associated with changes in U5MR. A 1% increase in the provincial gross domestic product (P=0.042) and the doctor-to-population ratio (P<0.001) was associated with 3% and 6% reductions in U5MR, respectively. Conversely, a 1% increase in the bed-to-population ratio (P<0.001), age-specific fertility rate (P=0.004), and total fertility rate (P<0.001) was associated with increases of 19%, 5%, and 117% in U5MR, respectively. The midwife ratio (P=0.433) and vaccine availability at primary health centers (P=0.851) were not significantly associated with U5MR. Conclusion: Improving the U5MR requires equitable healthcare access, addressing doctor shortages with incentive-based placements, enhancing healthcare facilities, and implementing policies to reduce teenage pregnancies through sex education and contraceptive promotion.