The research will test the hypothesis that a scalable behaviour change intervention can improve hand-washing practices in rural Indian households. The intervention will be designed using a social marketing approach and will use motivational messages targeting key audiences rather than educational messages about germs and disease which previously have been found ineffective. The intervention will be designed for low-cost, scaleable delivery using a series of visits to target villages by a two-person team on a motorbike. The key goal of the study is to determine the effectiveness of a scaleable, social marketing intervention to promote hand-washing with soap.

The study will take the form of a cluster-randomized, controlled intervention trial. Villages will be randomized to receive either the intervention or no intervention. The primary outcome measure will be the proportion of key events (defecation, faecal contact or food handling) accompanied by hand-washing with soap. These data will be collected by direct observation. A secondary outcome measure will be the number of soap movement episodes. These data will be collected in a sub-sample of households by using electronic motion detectors embedded in bars of soap. Additionally, questionnaires will be used to collect data on social norms, self-reported soap use and habitual soap use. All data will be collected pre and post-intervention.

Inclusion Criteria:

• households with children of primary school age or younger

Exclusion Criteria:

• households without school-aged or younger children