Hamadan University of Medical Sciences Journal of Research in Health Sciences 2228-7795 25 1 2025 01 01 How Sociodemographic, Water, and Sanitation Factors Influence Diarrhea in Children Under Five: Insights from Indonesia’s Underdeveloped Regions e00636 e00636 10.34172/jrhs.2025.171 EN Sailent Rizki Sari Simaremare https://orcid.org/0009-0007-8116-8479 Basuki Rachmat https://orcid.org/0000-0002-2888-8721 Wahyu Pudji Nugraheni https://orcid.org/0000-0002-7129-809X Debri Rizki Faisal https://orcid.org/0000-0002-2841-5123 Muhammad Nirwan https://orcid.org/0000-0002-9994-6052 Mara Ipa https://orcid.org/0000-0002-4831-6536 Tities Puspita https://orcid.org/0000-0002-4287-3657 Dea Anita Ariani Kurniasih https://orcid.org/0000-0002-6159-0652 Felly Philipus Senewe https://orcid.org/0000-0002-5765-7172 Journal Article 10.34172/jrhs.2025.171 2024 08 22 2024 09 20 Background: Despite the decrease in prevalence from 18.5% in 2013 to 12.3% in 2018, diarrhea presents a major public health challenge in Indonesia which leads to significant mortality. This study investigated factors influencing diarrhea among children under five years of age in underdeveloped regions of Indonesia, where disparities from other regions are significant. Study Design: A cross-sectional study. Methods: This study obtained data from National Basic Health Research conducted in 2018. Sixty underdeveloped regions of Indonesia, with a total of 9243 children aged 0-59 months, were included. Chi-square, bivariate, and multivariate analyses were conducted to determine factors influencing the prevalence of diarrhea in children under 5 years of age. Results: Multivariate analysis revealed that the age categories of 12-23 months (OR: 1.73; 95% CI: 1.48, 2.02) and 24-35 months (OR: 1.31; 95% CI: 1.11, 1.53), awareness of a nearby hospital (OR: 0.74; 95% CI: 0.63, 0.86), and history of acute respiratory infection (ARI) in the past month (OR: 1.99; 95% CI: 1.66, 2.40) were associated with diarrhea in children under the age of five in underdeveloped regions of Indonesia. In contrast, the environmental factors analyzed further in the study were not significantly associated with the prevalence of diarrhea in children under five years of age in underdeveloped regions of Indonesia. Conclusion: These findings suggest that the child’s age, the child’s history of ARI, and household awareness of nearby hospitals are critical factors associated with the child’s diarrhea in underdeveloped regions of Indonesia.