It’s called the “Hawthorne Effect” – a phenomenon whereby people’s behavior changes when they know someone is watching them. A new study from Santa Clara Valley Medical Center (SCVMC) in San Jose, Calif., has now found that even doctors and nurses can be affected by it when it comes to hand-washing. The study found that compliance with hand hygiene changed dramatically when health professionals knew they were being watched.

Although hand washing is one of the best, and easiest, ways to stop the transmission of infection-causing bacteria, and is a top priority in the nation’s hospitals. human behavior is hard to change. According to the Centers for Disease Control and Prevention (CDC), health care providers wash their hands less than half the time they should. The World Health Organization (WHO) reports that the figure is as low as 40 percent.

A lot of hand washing is necessary to maintain compliance. According to CDC associate director of science Dr. Clifford McDonald, doctors and nurses working in the intensive care unit may have to wash their hands over 100 times during an eight-hour shift.

During the study, SCVMC researchers used two types of auditors to assess hand hygiene. First were Infection Prevention (IP) nurses, who are well-recognized throughout the hospital as the hygiene police. Second were high-school and college-aged volunteers who were trained to perform the same assessments, but were not recognized by the hospital staff.

A pattern quickly began to emerge. IP nurses found much higher compliance rates in hand washing than the volunteers, apparently due to the Hawthorne Effect. One IP nurse, Lisa Hansford, told ABC News that she would sometimes notice a doctor or nurse not using the hand sanitizer. When they would notice that Hansford was there they would quickly wash up.

Researchers found that compliance with hand washing was about 57 percent, as observed by the IP nurses. Hospital volunteers, who blended in and were not recognized as hygiene auditors, recorded compliance rates of only about 22 percent. They initially thought that perhaps compliance was being recorded differently by the two groups, but extra measures ensured that this was not the case. It appeared that the difference just had to do with the providers knowing when they were being watched.

McDonald encourages patients to get involved, and not hesitate to remind their doctor or nurse to wash their hands. “If we can get the patients more involved in that – and get them to be able to speak up, that is really the main thing,” he said.

In most environments, alcohol rubs are the preferred method for cleaning the hands. They are less irritating to skin and more effective at destroying bacteria. They are also easier than soap and water.