Social influence and changing hand-washing behaviour

BBC News reports a neat study by LSHTM where the influence of different types of messages on people's use of soap in handwashing was monitored unobtrusively in a motorway service station. Different classes of message, all containing the word 'soap', were presented on an LED display, visible as people entered the washroom (no visual information design beyond keeping the message length to 48 characters to fit the display).

Not suprisingly, baseline levels of soap use differed for men and women (erm, in case you're wondering, men less likely to wash their hands (or use soap) than women). More surprisingly men responded particularly well to disgust inducing messages, such as 'Don't take the loo with you - wash with soap'; whereas women responded better to messages that activated their existing knowledge, such as 'Water doesn't kill germs, soap does.' But both men and women responded well to messages that included an element of social influence, e.g. 'Is the person next to you washing with soap?' And, for men at least, the stronger messages worked better the more people there were in the washroom at the time of seeing the message. Yet another example of the potential for using social norms to influence behaviour (see also here and here).