Cluster-randomised trial to test the effect of a behaviour change intervention on toilet use in rural India: results and methodological considerations

Abstract

Background Effective and scalable behaviour change interventions to increase use of existing toilets in low income settings are under debate. We tested the effect of a novel intervention, the ‘5 Star Toilet’ campaign, on toilet use among households owning a toilet in a rural setting in the Indian state of Gujarat. Methods The intervention included innovative and digitally enabled campaign components delivered over 2 days, promoting the upgrading of existing toilets to achieve use by all household members. The intervention was tested in a cluster randomised trial in 94 villages (47 intervention and 47 control). The primary outcome was the proportion of households with use of toilets by all household members, measured through self- or proxy-reported toilet use. We applied a separate questionnaire tool that masked open defecation questions as a physical activity study, and excluded households surveyed at baseline from the post-intervention survey. We calculated prevalence differences using linear regression with generalised estimating equations. Results The primary study outcome was assessed in 2483 households (1275 intervention and 1208 control). Exposure to the intervention was low. Post-intervention, toilet use was 83.8% in the control and 90.0% in the intervention arm (unadjusted difference + 6.3%, 95%CI 1.1, 11.4, adjusted difference + 5.0%, 95%CI -0.1, 10.1. The physical activity questionnaire was done in 4736 individuals (2483 intervention and 2253 control), and found no evidence for an effect (toilet use 80.7% vs 82.2%, difference + 1.7%, 95%CI -3.2, 6.7). In the intervention arm, toilet use measured with the main questionnaire was higher in those exposed to the campaign compared to the unexposed (+ 7.0%, 95%CI 2.2%, 11.7%), while there was no difference when measured with the physical activity questionnaire (+ 0.9%, 95%CI -3.7%, 5.5%). Process evaluation suggested that insufficient campaign intensity may have contributed to the low impact of the intervention. Conclusion The study highlights the challenge in achieving high intervention intensity in settings where the proportion of the total population that are potential beneficiaries is small. Responder bias may be minimised by masking open defecation questions as a physical activity study. Over-reporting of toilet use may be further reduced by avoiding repeated surveys in the same households. Trial registration The trial was registered on the RIDIE registry (RIDIE-STUDY-ID-5b8568ac80c30, 27-8-2018) and retrospectively on clinicaltrials.gov (NCT04526171, 30-8-2020).

The use of behavioural-science informed interventions to promote latrine use in rural India: a synthesis of findings

“…The Swachh Bharat Mission is likely responsible for the increase in self-reported latrine use in control areas, but the increase in the intervention arms that was beyond that observed in the control arms can be attributed to the evaluated interventions. This finding is consistent with the results the individual studies reported in their independent analyses, which indicated positive effects on latrine use in Karnataka, Odisha, and Gujarat, with null effects in Bihar (Caruso et al, 2019b;Chuahan et al, 2019;Friedrich et al, 2019;International Initiative for Impact Evaluation, 2020;Schmidt, Wolf-peter, Chauhan et al, 2020;Viswanathan et al, 2019). However, the calculation of the average effect across all four studies has the added benefit of being both statistically more powerful and applicable to a broader set of contexts.…”

“…This study builds on the work of the four independent impact (Caruso et al, 2019b;Chuahan et al, 2019;Friedrich et al, 2019;International Initiative for Impact Evaluation, 2020;Schmidt, Wolf-peter, Chauhan et al, 2020;Viswanathan et al, 2019). By using a common analytical approach to synthesize findings across studies, we are able to identify similarities in predictors of latrine use, such as sex and caste, and differences in predictors of latrine use, such as age, across these four states.…”

“…Three of the four studies collected data on the same households at baseline and endline. The fourth, which took place in Gujarat, used a repeated cross sectional design, interviewing different households at baseline and endline due to concern about respondent fatigue (Schmidt, Wolf-peter, Chauhan et al, 2020). 1.…”

Effect of a low-cost, behaviour-change intervention on latrine use and safe disposal of child faeces in rural Odisha, India: a cluster-randomised controlled trial

“…During the trial, no adverse events were reported. 31 and Gujarat (4•6%), 29 while the study in Bihar 32 reported null effects. Only the intervention in Karnataka aimed to increase safe disposal of child faeces, and found no effect.…”

Norms and Social Network–Centric Behavior Change Intervention (Nam Nalavazhvu) for Improved Toilet Usage in Peri-Urban Communities of Tamil Nadu: Protocol for a Cluster-Randomized Controlled Trial

“…Despite increased access to toilets, in many communities, complex sociocultural norms, along with technological and financial barriers, prevent individuals from using a toilet every time or exclusively using a toilet for defecation purposes [6][7][8]. Recent behavior change interventions designed to promote toilet use in rural India yielded, on average, a 5% increase in reported use amongst toilet owners, which is comparable to results generated by SBM [9][10][11]. Sustaining exclusive toilet use among all household members is a national priority for the current SBM 2.0, also known as the Open Defecation-Free plus scheme [12].…”