Prevalence and determinants of diarrhoea among children under five years: A pooled facility-based cross-sectional study across three ecological zones in Ghana

Background Diarrhoea remains a major cause of morbidity and mortality among children under five years in sub-Saharan Africa. Although national estimates are available in Ghana, district-level evidence across different ecological settings is limited. This study estimated the prevalence and determinants of diarrhoea among children under five across three geographically diverse districts in Ghana. Methods A pooled analysis of three facility-based cross-sectional studies was conducted in the Ga West Municipality, Gomoa East District, and Jirapa Municipal District of Ghana. A total of 1,266 caregiver–child pairs (422 per district) were selected using stratified random sampling. Data were collected through structured interviewer-administered questionnaires. The primary outcome was caregiver-reported diarrhoea within six months preceding the survey. Multivariable logistic regression was performed to identify independent determinants of diarrhoea at both district and pooled levels using STATA version 17. Results The pooled prevalence of diarrhoea was 66.4% (95% CI: 63.7–69.0), with marked district variations: 91.7% in Ga West, 72.3% in Gomoa East, and 34.8% in Jirapa.In the pooled multivariable model, children in Gomoa East (AOR = 0.24; 95% CI: 0.12–0.45) and Jirapa (AOR = 0.07; 95% CI: 0.03–0.13) had significantly lower odds of diarrhoea than those in Ga West. Children aged 9–16 months (AOR = 3.47; 95% CI: 1.69–5.47), 17–25 months (AOR = 5.07; 95% CI: 3.05–8.44), and 26–59 months (AOR = 3.63; 95% CI: 2.14–6.14) had higher odds of diarrhoea than infants aged 1–8 months, and unimproved water source was independently associated with increased odds (AOR = 1.99; 95% CI: 1.19–3.36). Protective factors included tertiary education (AOR = 0.33; 95% CI: 0.19–0.57), health insurance enrolment (AOR = 0.60; 95% CI: 0.37–0.95), and availability of handwashing facilities (AOR = 0.53; 95% CI: 0.38–0.74), while caregiver knowledge that handwashing prevents diarrhoea (AOR = 3.44; 95% CI: 1.81–6.54) and rotavirus vaccination (AOR = 3.04; 95% CI: 1.69–5.47) were paradoxically associated with higher odds. Conclusions Diarrhoea burden among children under five remains high and varies considerably across districts in Ghana. Strengthening water, sanitation, and hygiene interventions and targeting vulnerable age groups, and addressing underlying district-level drivers may help reduce the burden of childhood diarrhoea.