A comparison of prompts and feedback for promoting handwashing in university restrooms

Choi et al. (2018) tested two cheap ways to make college students wash their hands. They hung either prompt signs or small digital feedback screens above sinks in six busy university restrooms. Observers quietly counted how many people washed after using the toilet.

The team ran a multiple-baseline design across the six bathrooms. Prompts came first, then they swapped to feedback that showed a green check and the day’s percent-washed score.

Feedback beat prompts hands-down. When the screens went up, hand-washing rose higher and stayed there in every restroom. The simple signs alone had only lifted it a little.

Walmsley et al. (2013) found the same edge for feedback, but with students who had disabilities. Their package added a daily lottery and Glo Germ training. The extra parts helped that special-ed group, yet the core driver—feedback—matches Choi’s cleaner test.

Bowman et al. (2019) ran a group lottery for 170 staff in a large facility. Their lottery kept hand-washing high for two years. Choi’s study shows you can skip the lottery and still win if you give people quick visual feedback instead.

Critchfield (1996) used posted signs in campus restrooms too, but to stop graffiti. Signs alone wiped out the scribbles. Hand-washing is different; here signs falter and feedback shines. Same setting, same cheap tool, different behavior, different result.

If you consult for a school, gym, or clinic, swap tired reminder signs for a small feedback display. A $30 counter and smiley face can outwork years of polite “Wash Your Hands” posters. Try it Monday: tape a paper tally sheet by the sink and update it hourly—you may see an instant jump.