Does Targeting Children with Hygiene Promotion Messages Work? The Effect of Handwashing Promotion Targeted at Children, on Diarrhoea, Soil-Transmitted Helminth Infections and Behaviour Change, in Low- and Middle-Income Countries

The purpose of this systematic review is to assess if promoting the practice of handwashing with soap (HWWS), designed to reach children in low- and middle-income countries (LMICs), is effective at increasing handwashing behaviour and consequently reducing diarrhoea and soil-transmitted helminth (STH) infection among children and their families. Systematic reviews have consistently shown that HWWS is effective at reducing diarrhoeal diseases such as pneumonia and diarrhoea, which are among the leading causes of child mortality globally.

The main finding from the review is that the evidence base for child-focused handwashing promotion in LMICs is extremely scarce. Only 8 relevant studies were found and included in the review, conducted in July 2016: 7 cluster-randomised controlled trials and one cluster non-randomised controlled trial. None of the studies were found to be of high quality, and the large majority were at high risk of bias. Studies were conducted across 6 different countries: Malaysia, Peru, India, Egypt, China, and Kenya. All 8 studies sought to reach children aged 5-12 attending primary school but were heterogeneous for both the type of intervention and the reported outcomes, so results were synthesised qualitatively.

The researchers included interventions that promoted handwashing (with or without soap) at any specified key moment, for example: after toilet use (defaecation or urination), before preparing or handling food, before eating, after sneezing and coughing, upon arriving at school, after playing with soil, and during bathing. Intervention activities could include, for example: hygiene education, posters, group discussions, theatre, peer-monitoring, teacher monitoring, handwashing pledges, videos, comic books, songs, poems, games, drawing, puppet shows, mascots, rewards, competitions, and environmental cues.

Of the different interventions reported, no one approach to promoting handwashing among children appeared most effective. Table 3 in the report shows a summary of the outcomes measured in each study and if a positive effect was observed. In brief:

• With regard to STH, only one of the 3 studies identified showed a statistically significant reduction in A.lumbricoides infection in children, whilst two of the studies showed a significant reduction in A.lumbricoides intensity. These studies, however, may have been affected by bias due to a lack of blinding of the assessors. In one study that did blind the laboratory technologists assessing STH infection, and therefore was at a low risk of detection bias, no significant effect on A.lumbricoides infection was recorded.
• Handwashing promotion designed to reach children was only reported to have a significant effect on diarrhoea in the intervention target children in one study, in which handwashing was obligatory and teacher-supervised, potentially masking the true effects of the other hygiene promotion activities in this study. No other significant effects on diarrhoea incidence were reported in the other studies; however, incidence of diarrhoea was measured by self-report or through caregiver reports across all studies. As the responders were not blinded to the intervention, these reports are at high risk of response bias.
• All 3 of the studies in this review that used hygiene-related knowledge as a secondary outcome measure of intervention effect recorded a significant increase in knowledge post-intervention. However, the researchers contend that knowledge is not a good proxy indicator of behaviour change, as it does not necessarily translate into behaviour change. They point to Gyorkos' (2013) study, where children in receipt of the intervention scored significantly higher on a STH-related knowledge survey, but no significant change in handwashing behaviour was recorded. This intervention also had no significant effect on A. lumbricoides infection. "Although knowledge is necessary for behaviour change, it is not always sufficient and thus studies assessing the effect of handwashing promotion interventions should also include direct measures of behaviour change wherever possible." Only 3 of the 8 studies used direct observations to measure handwashing behaviour change, whilst the remaining studies measuring handwashing behaviour used self-report, via knowledge, attitudes, and practices (KAP) surveys, or soap consumption as a proxy measure. Only one of the studies with observed handwashing behaviour saw an overall statistically significant increase in the handwashing practices of children post-intervention compared to pre-intervention.

The researchers explain that the range of methods used to assess changes in behaviours across the studies made direct comparisons of findings difficult. Meta-analysis would be facilitated, they say, if future studies used more consistent measures of behaviour change to enable comparison. "Direct observation should be the outcome measure selected where possible to improve the validity of results. Furthermore, a standard unit of measurement, such as the proportion of participants HWWS at a specified moment, for example after defecation, would better enable comparative analysis. The use of covert video cameras in both schools and homes has become increasingly common; however, video surveillance has also been shown to introduce reactivity...and remains logistically difficult and expensive."

They also point out that all of the handwashing promotion interventions identified in this review were designed to reach children attending primary school. There is a clear lack of handwashing promotion interventions focused on teenagers, who may be in caregiving roles. Another overlooked group, identified by this review, is children who do not attend school, the numbers of whom are substantially higher in LMICs than in high-income countries.

Due to the limited number of studies and heterogeneity of interventions, the researchers were not able to assess the relationship between intervention effectiveness and the duration or intensity of the intervention. However, one systematic review of school-based interventions to modify dietary behaviour found no relationship between intervention intensity and effectiveness.

In short, the current paucity of evidence in this area does not permit any recommendations to be made as to the most effective route to increasing handwashing with soap practice among children in LMIC. However, the researchers point out that there has been some recent innovation in the science of changing handwashing behaviour. The Behaviour Centred Design (BCD) framework offers a new generalised approach, aiming to change behaviour through surprise, revaluation, and disruption of performance rather than traditional "messaging". It has been used successfully in the design and evaluation of handwashing interventions - for example, the SuperAmma programme in rural India. Pilot research in Bangladesh found large, sustained changes in handwashing behaviour associated with nudges - environmental changes in schools that included brick paths and painted symbols that prompted handwashing behaviours. Larger trials examining the effect of environmental modification on handwashing outcomes in schools are underway. "Whilst more evidence is needed, environmental modification may present a viable approach to changing handwashing behaviours in schools."