Table 4.
Studies investigating the existence of community sanitation coverage thresholds for diarrhoea impacts.
| citation | location | level of sanitation service provision | community coverage threshold | impact | study design |
|---|---|---|---|---|---|
| Andres et al. (2014) | India, rural | basic sanitation services | two thresholds: ∼30% (before 30% basically no change on diarrhoea) and ∼75% (around 50% of diarrhoea reduction after 75%) | 47% diarrhoea reduction in children communities in a village with 100% sanitation coverage compared to children in communities with 0% coverage | cross-sectional |
| Harris et al. (2017) | Mali, rural | sanitation facilities (including basic, shared and unimproved) | no threshold (tested for 20%. 40% and 60% sanitation coverage), no association between increased sanitation coverage and diarrhoea | – | cross-sectional |
| Jung et al. (2017b) | various low-income | basic sanitation services | threshold at 60% | 56% diarrhoea reduction at 100% community coverage with basic sanitation (OR 0.44 (0.29, 0.67)), 18% diarrhoea reduction < 60% coverage (OR 0.82 (0.77, 0.87)) | cross-sectional (DHS surveys) |
| Larsen et al. (2017) | various | sanitation facilities (including improved and unimproved private facilities) | threshold between 30% and 100% | 6% diarrhoea reduction (AOR 0.94 (0.91–0.97)) for children with household-level sanitation access in communities with 100% vs. 1–30% coverage | meta-analysis of survey data |
| Wolf et al. (2018a) | various | mainly basic sanitation services, depending on study | threshold at ≥75% | 45% diarrhoea reduction in high coverage studies versus 24% in low coverage studies (five studies with ≥85% community coverage (RR 0.55 (0.34, 0.91)) versus 16 studies ≤65% coverage (RR 0.76 (0.51, 1.13))) | systematic review and meta-analysis of intervention studies |
OR: odds ratio, AOR: adjusted odds ratio, RR: relative risk; basic sanitation includes improved sanitation facilities that are not shared between two or more households (WHO and UNICEF, 2017).