Two weird nudges boost hospital hand-washing

About 33 percent more people washed their hands when a photo of male eyes appeared above the hand sanitizer. A citrus smell increased use of the hand sanitizer to 46.9 percent. (Credit: "lemon face" via Shutterstock)

Two simple nudges—a picture of a man’s staring eyes and a citrusy smell—can get more people to wash their hands at the hospital, according to new research.

“Appropriate hand hygiene is considered to be essential practice in clinical environments to prevent healthcare-associated infections,” says Ivo Vlaev of Warwick Business School. “Yet low rates of hand-washing are widely reported and this was reconfirmed in this study, where only 15 percent of staff and visitors to an intensive care unit were observed to use the hand-washing station.”

Vlaev and colleagues report that the picture of a man’s eyes resulted in a third more people washing their hands, while the citrus smell boosted hand-washing by almost 50 percent.

For the study in the journal Health Psychology, the researchers experimented with psychological priming, which is the process where exposure to certain cues—for example words, smells, or images—alters behavior without the person being aware of the impact of the cue on their actions.

Men’s hands and women’s eyes

A trial took place in a surgical intensive care unit at a teaching hospital in Miami, Florida. A total of 404 healthcare workers and visitors were observed to see if they washed their hands by using the hand sanitizer next to the door before entering a patient’s room.

In the control group, of 120 visitors just 18 washed their hands (15 percent). Men on the whole seemed far sloppier, with only five out of 54 (9.26 percent) washing their hands, compared to 13 out of 66 women who washed their hands (19.70 percent).

A total of 124 visitors saw the pair of eyes positioned above the alcohol hand gel dispenser.

[Wash your hands! But turn down the heat]

When exposed to a photograph of male eyes there was a statistically significant increase in hand-washing of 33.3 percent. However, when the photograph was of female eyes even less, 10 percent, washed their hands.

Again men tended to comply with hand hygiene far less than their female counterparts with 21 women influenced by the male or female eyes and only five men, with just one man motivated by the female eyes to wash his hands.

“This may be because male eyes cue different feelings, thoughts, or emotions than female eyes,” says Vlaev.

“In many previous studies examining gender differences in exerting social influence more generally, men have been found to exert more influence than women and this may explain the differences seen. However, it is important to clarify the male eyes showed used more facial musculature, often perceived as anger or threat, so this could have influenced the observed individuals.”

Citrus smell

There were 160 individuals observed who were exposed to a citrus smell and they were significantly more likely than the control group to wash their hands, with 46.9 percent using the alcohol hand gel dispenser.

The citrus smell seemed to spur more men into action with 35 out of 83 males observed to wash their hands (42.17 percent). Women again complied more often, however, with 40 out of 77 (51.95 percent) complying.

“Further work could look more fully at gender differences in response to priming-based interventions; whether healthcare workers are affected differently than visitors; and whether the impact is strengthened or diluted through repeated exposure,” adds Vlaev.

Vlaev’s coauthors are from Imperial College London and the University of Miami.

Source: University of Warwick