Effectiveness of Mass Media Campaigns to Improve Handwashing-Related Behavior, Knowledge, and Practices in Rural Bangladesh.

Water, sanitation, and handwashing interventions that use intensive interpersonal communication improve targeted behaviors, but are expensive at scale. Mass media is an alternative that could reach more people at lower cost but has rarely been rigorously evaluated. We assessed the effectiveness of a mass media campaign in improving handwashing knowledge and practices in rural Bangladesh. We conducted a cross-sectional assessment before the campaign among 8,947 households and again after 4 months of the campaign among 8,400 different households in the same areas. Trained enumerators conducted spot checks of water, sanitation, and hygiene facilities, and recorded reported knowledge and practices. We compared these outcomes after versus before the campaign using generalized linear models with robust standard errors. After the media campaign, caregivers were more likely to recall ≥ 3 messages regarding handwashing (prevalence ratio [PR] = 1.44, 1.34-1.55), sanitation (PR = 1.45, 1.35-1.55), and safe water (PR = 1.17, 1.08-1.26). After the campaign, the prevalence of using soap and water during handwashing demonstrations was higher among caregivers (PR = 1.15, 1.12-1.19) and children (PR = 1.31, 1.22-1.41). Hands were more commonly observed to be visibly clean among caregivers (PR = 1.14, 1.07-1.20) and children (PR = 1.13, 1.05-1.21). Soap and water was more commonly observed in handwashing stations near latrines (PR = 1.12, 1.06-1.19) and in cooking/eating places (PR = 1.09, 1.01-1.18). Our findings indicate improved handwashing knowledge and behaviors following a mass media campaign. This promising approach can be deployed to improve water, sanitation, and hygiene practices at scale and should be evaluated in other contexts.