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

Evidence scope and study design

This systematic review assesses cost-effectiveness and benefit-cost analyses of promoting handwashing with soap in domestic, educational, and childcare settings globally.
The search covered studies from 1980 to 2025 across multiple databases plus grey literature, focusing on full economic evaluations that compare costs with outcomes.
Interventions included information provision, motivational campaigns, and/or installation of handwashing facilities.
Study quality was appraised using the Consolidated Health Economic Evaluation Reporting Standards (CHEERS).

Studied evidence and methods

A total of 15 studies were identified, with 3 conducted in high-income countries.
About one-third of the studies collected empirical data from interventions actually implemented; the remaining two-thirds modeled outcomes using secondary data.
Among the studies that reported cost per disability-adjusted life-year (DALY) averted and were of at least medium quality, the reported costs ranged from 37 to 937 US dollars per DALY averted (in 2024 prices).
Of these, two studies indicated cost-effectiveness relative to plausible country-specific thresholds.
Only one medium- or high-quality study on benefit-cost analysis provided a mean benefit-cost ratio, which was 2.1 under assumptions of medium adoption (40% of the population) and adherence (50% of those adopting).

Main findings on economic value

Across higher-quality evaluations, interventions that achieve and sustain broader handwashing behavior adoption are very likely to be cost-effective.
The reviewed benefit-cost evidence suggests positive returns when adoption and adherence are at moderate levels, though this conclusion is limited by context and data availability.
There is substantial heterogeneity in study design, outcome measures, and data sources, which constrains direct cross-study comparisons.

Contextual limitations and gaps

Adoption dynamics over time are infrequently measured or modeled, limiting understanding of long-term cost-effectiveness.
Most analyses did not simultaneously value reductions in diarrhoea and respiratory infections; notably, no study focused on diarrhoea with linked valuation of respiratory infection reductions.
Alcohol-based hand rub interventions were excluded, potentially omitting relevant costs and outcomes.
Cost-effectiveness thresholds vary and remain uncertain, complicating universal interpretation of “cost-effective.”

Implications and open questions

The evidence supports promoting handwashing with soap as a potentially cost-effective strategy when adoption and sustained behavior change are achieved.
More empirical evaluations are needed that compare multiple promotion approaches, incorporate longitudinal adoption trajectories, and explicitly value both diarrhoeal and respiratory infection outcomes.
Future work should clarify context-specific cost-effectiveness thresholds to aid decision-making across settings.