Nudging Hand Hygiene Compliance: Insights From a Large-Scale Field Experiemnt on Hospital Visitors
In a large-scale field experiment published in the Journal of Hospital Infections, we tested a Behavioural Insights Concept (BIC) that effectively increase hand hygiene compliance at hospitals.
With the onset of the COVID-19 pandemic, the importance of hand hygiene was thrust into the spotlight like never before. While basic hand cleansing has long been advocated as a means of illness prevention, achieving compliance, particularly in healthcare settings, remains a challenge. With baseline hand hygiene compliance often around 3% to 10% in healthcare settings, healthcare-associated infections (HCAIs) continue to pose a significant threat to patient safety, making the need for effective hand hygiene practices all the more critical.
In a large-scale field experiment, we explored and refined the various components of a Behavioural Insights Concept (BIC) that we have developed over the years — a BIC aimed at increasing hand hygiene compliance among hospital visitors and which may easily be implemented at hospitals around the world.
Over 50 days, we observed the behaviour of over 46,000 visitors entering a hospital in Denmark, experimenting with the various features of the concept as applied to the generic situation of encountering a hand sanitiser in a hospital foyer.
Varying seemingly irrelevant features
The findings from the field experiment were highly interesting. By varying seemingly irrelevant features such as the placement and salience of hand sanitiser stations, compliance rates significantly increased from a baseline of 0.4% to as high as 19.7% (and ultimately 47.6% during the COVID-19 pandemic). More specifically, exploring variations of the behavioural insights integrated into the concept showed how particular features were crucial in nudging compliance rates up.
The field experiment tested 4 key nudges in 9 combinations.
The four key nudges were:
1. Situation, more specifically location of hand sanitiser station in the foyer (original baseline at the reception vs. various realistic placements in and just before entering the foyer)
2. Salience, more specifically a pink sign saying “sanitiser” (present vs. absent)
3. Persuasion, more specifically a pink banner usually implemented as part of the annual national hand hygiene campaign (present vs. absent)
4. Norm, more specifically an assertive norm communicated using pink duct tape line on floor by sanitiser (present vs. absent).
These components were varied in a test of 9 relevant combinations against the baseline scenario.
Figure 1. Ilustrations of the 9 tested combinations and the two not included in the field experiment. Illustrations by iNudgeyou.
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Detailed Results and Findings
While other experiments have been conducted analysing hand sanitation compliance in a similar manner, none have looked at as large a sample set as this one, nor taken into account the interaction of the different nudges at once. For these reasons, analysis of the data also revealed some detailed results and intriguing insights.
First, it is a noticeable finding every variation nudged an increase in hand hygiene compliance above the baseline (0), which was measured to be only 0.43% on average. Although it might be hard to fathom, this baseline level is actually not unusual compared to baselines in the many hand hygiene experiments we have conducted over the years. Thus, given the realism and cost-effectiveness of every nudge tested, there seems no excuse for hospitals not to apply this approach immediately.
Second, the experiment revealed that the effect of then current and widely used (2) intervention of trying to persuade visitors to sanitise their hands by using a campaign strategy was close to non-existent (from 0.43% to 2.2%). This is not the first time that we find campaign strategies to close to no effect, or even negative effects — an interesting variation of which is found in scenario (9), where the presence of the campaign strategy is found to have a negative effect on compliance.
Third, the most effective combination of insights in nudging hand hygiene compliance turned out to be scenario (8) with the sanitiser placed before the entrance to the foyer (situation), visibly prominent with pink signage (salience), and a duct tape line on the floor to further encourage people to perceive it as boundary requiring an action (norm) — but no persuasion. Compliance in this case rose from 0.43% to 19.66%. This set-up is so easy to copy that there is no excuse not to.
Fourth, given the large number of observations and the quality of the data collection by our trained observers the experiment also allowed us to analyse moderators such as gender and the time-of-the-day. Here it turns out that women were more likely to be nudged to comply compared to men. It’s anyone’s guess as to why that might be the case. However, we speculate that there could be an increased appeal in annual campaigns use of the colour pink which is also the branded colour used in the national female breast cancer campaign. In addition, in the experiment we found no change in hand hygiene compliance relative to the time-of-the-day, which is otherwise suggested by experiments using fewer observations as well as a much-cited effect in the popular science literature.
The figure below shows the effects of the various combinations:
Figure 2. Hand hygiene compliance (%). Percentage of people sanitising their hands upon entering the hospital.
The effect of COVID-19
Shortly after we had finished the experimental protocol of the planned experiment, COVID-19 arrived on the scene. When conducting another series of hand hygiene experiments a year into the pandemic, we therefore decided to revisit the site where intervention (9) had been selected for implementation and measure how it performed under these new conditions.
Over the course of 4 days, we observed almost 5,000 visitors. Unsurprisingly, data showed that compliance had skyrocketed. Scenario (9) which had achieved only 13.95% compliance prior to COVID-19 shot up to 47.6%. Interestingly, our baselines in parallel experiments did not shoot up in the same way. In this light, there is a case for arguing that nudges may be conceived of as important ‘accelerants’ in efforts to create behaviour changes.
Conclusion
So, what can we conclude at this point? Most importantly, as increasing hand hygiene compliance is recognised as the foremost means to further reduce the risk of healthcare-associated infections (HCAIs) and improve patient safety, there is a strong case for implementing the tested and effective Behavioural Insights Concept, immediately. The scalability and cost-effectiveness of this concept makes it an invaluable tool in safeguarding public health without any excuses present.
Further, the findings and results of our field experiment underscore the value of working with Nudging and Behavioural Insights in the public healthcare sector. By testing — what for the untrained eye appear to be — seemingly irrelevant features of the situation of hand sanitisation, we have documented how Behavioural Insights Concepts can easily be implemented to encourage cleaner hands and potentially reduce the transmission of infections in healthcare settings.
Finally, we are of course also proud to have published these ground-breaking results in the As we continue to explore innovative Behavioural Insights Concepts addressing healthcare-associated challenges, nudging towards improved hand hygiene offers an instructive example of how this approach may work to create safer and healthier healthcare environments.
Reference:
Hansen, P.G., Larsen, E., Modin, A., Gundersen, C., Schilling, M. (2021) Nudging hand hygiene compliance: a large-scale field experiment on hospital visitors, Journal of Hospital Infection, 2021, ISSN 0195-6701, https://doi.org/10.1016/j.jhin.2021.09.009.
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