Cost-Effectiveness and Benefit-Cost Analyses of Promoting Handwashing With Soap: A Systematic Re

03 Apr 20264 min read0 viewsJournal Feed

GIST

by Ian Ross, David Bath, Joseph Wells, Robert Dreibelbis, Regina Ejemot-Nwadiaro, Joanna Esteves Mills, Giulia Greco, Catherine Pitt, Oliver Cumming Background Promoting handwashing with soap reduces risk of diarrhoea by 30% and respiratory infections by 17%. Handwashing promotion in nonhealthcare settings is widely considered cost-effective, but there is no systematic review on this topic.

To inform resource allocation decisions, we reviewed the state and quality of evidence regarding cost-effectiveness and benefit-cost of interventions promoting handwashing with soap in domestic, educational, and childcare settings globally. Methods and findings We searched Medline, Embase, Global Health, EconLit, and Web of Science for studies published from January 1, 1980 to September 3, 2025, as well as grey literature (PROSPERO CRD42021288727).

We included full economic evaluations comparing the cost of two or more interventions with their outcomes. We included interventions promoting the practice of handwashing with soap, including those providing information, motivational campaigns, and/or handwashing facilities.

We scored quality of reporting using the Consolidated Health Economic Evaluation Reporting Standards. We identified 15 studies of which 3 were in high-income countries.

Clinical Editorial

Scope and design context

The synthesis addresses interventions that promote handwashing with soap outside healthcare settings, spanning domestic, educational, and childcare environments globally.
Economic evaluation criteria required full comparisons of costs against outcomes, with interventions including information campaigns, motivational efforts, and/or provision of handwashing facilities.
Study quality was gauged using the Consolidated Health Economic Evaluation Reporting Standards (CHEERS).

Evidence landscape and study characteristics

A total of 15 studies were identified, with 3 conducted in high- or middle-income countries.
Study designs comprised a mix of empirical evaluations of implemented interventions (n=5) and purely model-based analyses using secondary data (n=10).
Among the high- or medium-quality studies reporting cost per disability-adjusted life-year (DALY) averted, estimates spanned from 37 to 937 US dollars (in 2024 prices).
Only two of these cost-per-DALY studies met the threshold for cost-effectiveness under plausible national benchmarks; the distribution of thresholds and contexts varied.
The sole high- or medium-quality benefit-cost analysis reported a mean benefit–cost ratio of 2.1, corresponding to moderate adoption (40% of the population) and adherence (50% of adopters).

Outcomes and signal strength

The evidence base demonstrates a likely favorable economic signal for handwashing promotion programs that achieve sustained behavioral adoption.
Notably, few investigations captured how adoption or maintenance evolves over time, limiting understanding of long-term economic trajectories.
There is a notable gap: no included analyses focused simultaneously on reductions in diarrhoeal disease and respiratory infections within a single valuation framework.

Contextual limitations and uncertainties

Alcohol-based handrubs were excluded from the review.
Uncertainty surrounding cost-effectiveness thresholds across settings remains substantial, complicating universal interpretation of “cost-effective.”
Several studies relied on modeled projections rather than empirical outcome data from real-world implementations.
Adverse or neutral results, as well as context-specific factors influencing adoption, were not consistently detailed across the included works.

Key implications for policy and research design

The available high-quality economic evaluations suggest handwashing promotions can be cost-effective when adoption and sustained use are achieved, though results are context-dependent.
More robust, comparative empirical studies are needed to evaluate different promotion modalities and to capture both diarrhoeal and respiratory infection outcomes within a single economic framework.
Future work should incorporate longer time horizons to reflect adoption dynamics and should explicitly value reductions in respiratory infections alongside diarrhoea, where feasible.