Level of Behaviour Change Achievable by Handwashing with Soap Interventions: A Rapid Review

What is the level of behaviour change that is possible in response to a successful hygiene intervention? How can this help inform programme design and monitoring? Which factors within each intervention may have contributed to a successful or sustainable intervention?

These are some of the questions guiding a rapid literature review of manuscripts/reports that: included information on an intervention to promote handwashing with soap, or an evaluation thereof; described an intervention that was delivered in a low- or middle-income country; was available in English; and preferably had a behaviour outcome or a health outcome with considerable data on behaviour. The authors primarily reviewed peer-reviewed articles as well as programme reports and other grey literature published from 2005 to date.

Eight successful interventions were included as part of this review. Five of them provided information on the underlying theories of behaviour change on which the interventions were based. For instance, Biran et al. used the Evo-Eco model as a framework to guide the interpretation and analysis of the formative research (see case study 3 within the document for further information on this model).

The interventions comprise both large- and small-scale initiatives in various settings, using different approaches. Most interventions used multiple methods. To cite only one example, a Bangladesh intervention, SHEWA-B (Sanitation, Hygiene Education and Water), engaged local residents to develop their own community action plans, which included targets for improvement in latrine coverage and usage, access to and use of arsenic-free water, and improved hygiene practices, especially handwashing with soap. Local residents, trained as "promoters", visited households, facilitated courtyard meetings, and organised social mobilisation activities such as sanitation and hygiene fairs and village theatre, with the intention of reaching a mass audience of individuals. The messages alerted participants to the presence of unobservable germs in the home environment and educated them about practices that could minimise the impact on health, such as handwashing with soap. "Although not explicitly stated in the other evaluation reports, all interventions would have needed to be acceptable to the community and ideally 'owned' by the community at large or championed by prominent members. In the intervention by Huda et al. in Bangladesh, the community motivators were financially compensated and the role was given a suggested to have a certain status in the community, both of which may have contributed to a motivated delivery of the intervention (Huda et al. 2012)."

All interventions provided data on handwashing at key times, and the majority measured handwashing through observation, with only one using solely self-report. Spot checks of facilities and handwashing demonstrations were additional proxy measures used in some of the reviewed interventions.

All 8 of the included interventions demonstrated increased handwashing with soap after a hygiene intervention:

1. Biran et al. 2014 (India) - 15% change in observed handwashing at key events after 6 weeks, (19% in intervention versus 4% in control group), and 31% change after 6 months (37% in intervention versus 6% in control group). The behaviour was sustained up to 12 months, at which point the control group had also received in the intervention, and hands were being washed at 29% of key events for both control and intervention.
2. Huda et al. 2012 (Bangladesh) - 14% change in observed handwashing with soap frequency after cleaning a child in the intervention group (36% at 18 month follow up versus 22% at baseline). In the control group this change was 3% (37% at 18 month follow up versus 24% at baseline).
3. Gautam et al. 2015 (Nepal) - 62% change in observed handwashing with soap before feeding a child, 45 days after the intervention (67% after intervention compared to 5% before the intervention). In the control group, the observed behaviour went from 7% at baseline, compared to 5% at follow up.
4. Scott et al. 2008 (Ghana) - 30% change in reported handwashing with soap after visiting the toilet or cleaning a child’s bottom, approximately three months after the intervention (as compared to reported handwashing with soap behaviour in unexposed group).
5. Langford et al. 2013 (Nepal) - After the intervention, all mothers in the intervention group report washing hands after visiting the toilet and cleaning a baby's bottom (100% for both activities in intervention group, as compared to 90.7% handwashing after toilet use and 83.7% handwashing after cleaning a baby in the control group, resulting in a 4% and 19% change respectively). Data collected through continuous 6-month evaluation.
6. Bowen et al. 2013 (Pakistan) - Intervention households were 3.4 times more likely than controls to have soap at their handwashing stations at study visit (97% in intervention households vs 28% at control households, resulting in a 69% change). Intervention households cited significantly more occasions for washing hands. Results were collected 5 years after the initial intervention.
7. Galiani et al. 2012 (Peru) - 6% increase in caregivers' knowledge on best ways to wash hands and an increase of 8% in terms of availability of water and soap for handwashing in intervention groups (as compared to baseline). In a subsample, 61% more households in the treatment group washed their hands with soap before eating (observed), as compared to the control group, 4 months after the intervention.
8. Contzen et al. 2015 (Ethiopia) - 46% increase in availability of handwashing activities (with water and soap) in the intervention arm receiving education and tippy-tap2 construction training 6 months after the intervention, as compared to the baseline group receiving education only (83% versus 37%).

Overall, these interventions show that achievable handwashing behaviour change ranges between 14%-67% increases in handwashing behaviour as measured by observation (sustained changes - 45 days to 18 months) and between 4%-46% as measured by self-report (post intervention and continuous assessment). Measures of sustainability of interventions are limited; one intervention showed sustained behaviour up to 45 days, and data from 2 interventions show that change in behaviour was sustained for at least 12 months. One intervention has been assessed after 5 years and still shows evidence of the sustained behaviour.

The authors explain that, due to the wide variation in setting and context in which the 8 interventions were implemented, the results cannot be directly compared to draw out "best approaches". In addition, the interventions included measure a range of handwashing behaviours, for example after visiting a toilet or before eating. They do note that it was found that handwashing reminders, such as stickers with eyes at the designated handwashing facility, can be used to prompt handwashing behaviour. Furthermore, knowledge of key handwashing times, or good handwashing "technique" does not necessarily translate into handwashing habit, nor does the provision of a handwashing facility automatically translate into use.

The authors conclude that, overall, "this area of research would benefit from for rigorous impact and process evaluation, subsequent modification of intervention design, and further testing of 'new generation' handwashing with soap interventions....Key factors which may contribute to success in behaviour change include baseline levels, follow up time post-intervention, and the exact handwashing times measured, in addition to a focussed intervention using various methodologies and approaches - carefully considered and grounded in behaviour change theory."

This report was produced for Evidence on Demand with the assistance of the United Kingdom (UK) Department for International Development (DFID) contracted through the Climate, Environment, Infrastructure and Livelihoods Professional Evidence and Applied Knowledge Services (CEIL PEAKS) programme, jointly managed by DAI (which incorporates HTSPE Limited) and IMC Worldwide Limited.