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Why can't people just wash their hands, and how to make them?

Image by Piron Guillaume

With Covid-19, the importance of handwashing has resurfaced. Our hands come into contact with numerous surfaces, which have been touched by many other people. We, in turn, go on to touch many other surfaces, including our face and our food. But we can break this cycle just by washing our hands - just the mere application of soap and water removes a lot of the bacteria 

The problem is people don't always wash their hands, or do so properly. A study from the University of Michigan estimates that only 5% of Americans wash their hands thoroughly with water and soap for at least 15 seconds. The Centre for Disease Control and Prevention in the United States recorded the hygiene practices of employees at hundreds of eateries. The result? 62% of employees in eateries failed to wash their hands. These are people who prepare our food!

A similarly low rate is observed among people who really should know better (this is an important hint about what changes behaviour - merely knowing is insufficient, stay tuned). 61% of medical professionals do not wash their hands properly, even though hygiene is critical as part of healthcare - contaminated hands touching a patient could cause major infections.

So how can we change people's behaviour? They obviously know what to do, but they won't do it. How can we get people to wash their hands?


Donna Armellino et al aimed to find out

They chose an intensive care unit (ICU) in northeastern USA for the study. The ICU had all the necessary parts to encourage easy handwashing. It was equipped with sanitisation dispensers, sinks in every room, and signs all around the unit reminding medical staff to wash their hands. Yet compliance rates were low - handwashing was almost non-existent.

The researchers got to work.

- They installed surveillance cameras around the ICU, capturing footage of sinks and sanitisation dispensers.

- These camera were on live 24/7, with feed being watched by auditors around the clock, clocking compliance rates. (Additionally, to ensure the auditors don't miss any incident, each door was outfitted with a motion sensor, to capture entry and exit into any room). 

- Finally, the medical staff were informed they were being watched.

- The researchers ran surveillance for a total of 16 weeks.

And the results? Out of 60,542 cases, staff washed their hands on only 3,933 occasions or 6.5% of the time. A truly tragic figure. Surveillance was not working.


So the researchers swung into plan B.

- the researchers placed an electronic board in each room

- each time a medical staff washed their hands, the numbers on the board went up. The numbers indicated the rate of handwashing for the current shift, the week, and the month. There was even some friendly competition between the doctors and the other medical staff. You can check out the electronic board in the picture below. 

Washing hands display board.png

So staff were able to get immediate feedback on how their team was doing.


And the results were astounding.


||  From the 6.5% during the initial trial that focussed on surveillance, handwashing rates rose to 81.6%! Even more impressive was that the rates didn't drop off with time. The experimenters continued measuring handwashing rates for the next 75 weeks, which saw an even higher average of 87.9%! The results were so astounding that the experimenters tested the same process (surveillance, and then electronic boards with immediate feedback) at another department. Same results.

So what is it about that electronic boards that worked so well, that got so much better results than surveillance? 3 major reasons:

  • Immediate rewards: It provides a small reward for hand washing - a good feeling - where staff can see immediately how their efforts (be it positive or negative) contributed to their team's performance. This good feeling comes from dopamine - a neuro-chemical produced in our brains. Most interestingly, dopamine causes us to want to take action to get the reward again. This means that the staff are not just motivated to hand-wash once, but repeatedly. Dopamine is a really interesting and chemical which is almost always misunderstood - read more about it here.

    Compare this with the typical warning signs which are negative in nature, of disease and of gloomy outcomes. These warnings in fact trigger much more inaction - because people tend to shy away from bad news. As a simple thought experiment, think about how much more eager you are to receive test scores when you know you've done well compared to when you know you've screwed up, or when you know someone is going to say something nice about you as compared to when you anticipate criticism. We are much more likely to take action to get a positive reward, then to take action to avoid an uncertain negative future. 


  • Social fit: Humans are social animals and we care how we fit into a social group. When we're on a team, we consider how much we're doing and how much everyone else is doing. It's the same for the medical staff, who know that their actions (or inaction) affect how everyone else on the team is viewed. Add in an element of competition, and the medical staff become even more eager to do well for their teams.

    Consider how the British government was able to get more people to pay their taxes on time. Instead of the usual warning letters preaching the importance for citizens to submit their taxes, compliance rate remained low. This is similar to the surveillance process in this experiment. But just adding in one line caused compliance rates to improve by 15% - "9 in 10 people in your neighbourhood have already submitted their taxes." Just that one line. And it's enough to make us think about social fit, how almost everyone else has already done their taxes, and how "I don't want to be the 1 in 10!"


  • A measure of progress: On the electronic boards, the staff are able to get a sense of not just how well the current shift is doing, but the weekly and monthly rates of handwashing. This provides a simple, clear, and achievable target to aim towards - can this shift to better than the average rates last week or last month? Can we get better? And the measure of progress probably contributed to handwashing rates continually rising, from 81.6% after 16 weeks of trialling with the electronic boards, to 87.9% over the next 75 weeks. Even though nothing new was added, it was the same electronic boards displaying the same information, the staff kept striving to do better.

Handwashing seems like a simple and obvious thing to do. Cognitively, we know we should be doing it. But some of us just fail to take action. Most of the time, to convince people to do the right thing, we endlessly try to remind them why it is the right thing to do, and all the bad things that would happen to them if they don't do it.

As it turns out, giving people information and warning is not a good strategy to change behaviour. All of us will attest to this - have you ever had an experience in your life where you knew what the right thing to do was, but just couldn't do it? Instead, to change behaviour, we often need more subtle methods, leveraging on wiring in our brains to make the action more attractive, for example, immediate rewards, social fit, and a measure of progress. In the related links below, you will find more examples of how people found unique ways to shape the behaviour of others:

Related links

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Why do Germans eat potatoes?

Why we save the one but not the many

How to get more donations for charity

How to encourage hotel guests to reuse their towels for the environment?
Movies or medication? Movies, of course

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