Maria Lapinski of Michigan State University, Erin Maloney of the University of Pennsylvania, Mary Braz of Westchester University and Hillary Shulman of North Central College said males were surveyed and self-reported washing their hands 75 percent of the time.
This led to a field experiment in which signs were posted in bathrooms that read "4 out of 5 Males Wash Their Hands," with pictures of students wearing Michigan State University hats and a guide to effective hand washing.
Researchers in the bathroom then recorded hand-washing behavior and marked how well the guide was followed. When the participants exited the bathroom they were approached by experimenters and willing participants filled out a questionnaire.
The hand washing increased to 86 percent, the researchers said.
The findings, published in Human Communication Research, suggested men exposed to a relatable message in the bathroom were more likely to wash their hands and ran the water longer than participants not exposed to the messages.
The findings could have huge implications on public health, particularly during cold and flu season, the researchers said.