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Hospital-acquired-infections (HAI’s) are a costly affair to patients and society as a whole. Acquiring a hospital infection creates additional suffering for the patient and it may at worst lead to death. Prolonged hospitalisation due to HAI’s also represents a massive financial burden to health care systems around the world. Improving hand hygiene behaviour in hospitals is among the most promising ways of preventing such HAI’s. This brief paper reports on a recent field experiment testing a simple nudge aimed at improving hand hygiene amongst hospital visitors.
Nudging Hospital Visitors' Hand Hygiene Compliance
iNudgeyou © 2016
Hospital-acquired-infections (HAI’s) are a costly
affair to patients and society as a whole. Acquiring
a hospital infection creates additional suffering
for the patient and it may at worst lead to death.1
Prolonged hospitalisation due to HAI’s also
represents a massive nancial burden to health
care systems around the world. Improving hand
hygiene behaviour in hospitals is among the most
promising ways of preventing such HAI’s.2 This
brief paper reports on a recent eld experiment
testing a simple nudge3 aimed at improving hand
hygiene amongst hospital visitors.
In Denmark, it has been estimated that 1 in every
10 hospitalised patients acquire an infection during
their hospitalisation.4 These incidents drive additional
health care costs and the Danish Health Care
System spends nearly 1 billion DKR on a yearly basis
accounting for the costs of prolonged hospitalisation.5
The hospital environment is rich on bacteria, even
one’s that only thrive within this specic environment.
These bacteria are a major threat to vulnerable and
weakened patients causing prolonged hospitalisation
and, at worst, death. Therefore it is of utmost
importance to try and eliminate the transmission
of bacteria and hand hygiene is the single most
important factor in reducing the transmission of
A lot of effort has been made to improve health care
workers’ hand hygiene compliance (HHC) and far
less has been done in order to maintain high levels of
HHC among visitors. To our knowledge there is only
one published investigation into this matter, which
in return yielded an increase in HHC from 0.52% to
Simon Carøe Aarestrup1, Frederik Moesgaard2, and Johannes Schuldt-Jensen3
1 Junior Researcher, iNudgeyou.
2 BSc, Business Administration & Psychology, CBS.
3 Junior Researcher, iNudgeyou.
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Nudging Hospital Visitors' Hand Hygiene Compliance
iNudgeyou © 2016
As the nudge approach dictates9, the authors of this
paper sat forth to develop a simple nudge and test
this in a eld experimental setting. The main objective
was to investigate how to further increase visitors’
use of hand disinfectant in a real-world setting.
The use of hand sanitizer is an active way of supporting
your relative in the recovery process. Throughout
all of the investigation it was assumed that hospital
visitors care about the well being of their hospitalised
loved ones and want to help setting them on their
feet again. Hence, what we were interested in was
to remove the obstacles that might possibly drive
the non-compliant hand hygiene behaviour causing
a gap between the visitors’ good intentions towards
their relatives and the visitors’ actual behaviour.
The nal intervention was made up of the three
nudge-functions, placement, colour and normative
One of the rst things we noticed at Gentofte
Hospital was the placement of the hand sanitizers.
At the Medical Department all hand sanitizers were
primarily located above the sinks inside the hospital
wards (See Fig.1). The choice of using hand sanitizer
is thereby offered at a seemingly late point in time
competing against the choice of approaching one’s
hospitalized relative.
The rst part of the intervention included a new
placement of the hand sanitizer. We introduced a
freestanding hand dispenser at the very beginning of
the Medical Department to ensure the least amount
of competing stimuli in the environment.
The hand sanitizers had a low degree of salience
in the original setup. The hand sanitizer packaging
was transparent which made it blend in with the
surrounding environment (See Fig. 1). This visual
attribute made the hand sanitizer less likely to catch
the visitors’ attention when entering the ward.
In order to work around the transparency problem we
introduced a red sign right above the freestanding
hand sanitizer as the second part of the intervention
(See Fig. 2). In the natural world the colour red is the
most common signalling color.10 Consequently, the
colour red is a substantial visual stimulus better at
directing our attention compared to other colours.10
Another aspect of the colour red, is the different
associations the colour brings along with it. The
colour red is used in trafc to catch drivers’ attention.
In trafc red means that you have to stop as opposed
to the colour green that invites you to move on. We
wanted to integrate this association into the layout of
the sign (See Fig. 2).
The nal function of the intervention was a text
message printed onto the red sign. It stated “Here we
use HAND DISINFECTANT in order to protect your
relative”. The text message on the sign was made up
of two different elements:
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Fig. 1 Original placement of the hand sanitizers.
Fig. 2 The placement of the hand sanitizer during the
intervention period.
Nudging Hospital Visitors' Hand Hygiene Compliance
iNudgeyou © 2016
The rst part of the text was constructed as a
normative message. Thus, we expected that it would
inform the visitors about the most accepted behaviour
in relation to hand hygiene at the hospital. People
who visit the hospital might nd it difcult to estimate
the right kind of behaviour in this particular context.
"… in order to protect your relative"
The second part of the text was used to make the
consequences of hand hygiene compliance more
tangible to visitors, by giving them a plausible reason
as to why they should engage in positive hand
hygiene behaviour.
Our eld experiment consisted of three different
conditions with 30 visitors observed in each condition
(N=90). First, the baseline condition was tested in
order to determine the general level of hand hygiene
compliance. Secondly, in our placement condition
we employed a freestanding hand dispenser at
the very beginning of the department. Thirdly, the
sign+placement condition made use of the new
placement as well as introducing the sign on top of
the hand dispenser. The data was gathered by direct
observation during ve concecutive days at Gentofte
In the wake of the eld experiment we ended up with
the following results. In the baseline condition only
3% of the visitors used hand disinfectant. Introducing
the new placement for the hand dispenser resulted
in 20% of the visitors using hand disinfectant. Finally,
with the combination of both the new placement and
the sign, hand hygiene compliance reached a level of
67% (See Fig. 3).
The groups showed an overall signicant difference
x2(df= 2, N = 90) = 14.45, p = .0007). Using a second
chi-square, we found that the “sign+placement”
group, were signicantly different from the other
two (x2(df= 1, N = 90) = 11.72, p = .0006). Using
a bonferroni correction for multiple comparisons on
both tests, they maintain signicance at p < 0.01.
The results from the eld experiment at Gentofte
Hospital clearly indicates that it is possible to increase
hand hygiene compliance among visitors by means
of changing the default placement and providing a
salient sign using a positively framed message. In
a broader perspective our results suggests that the
employment of behavioural insights is a valuable tool
to improve visitors' hand hygiene compliance.
SCA: corresponding author,
SCA and FM: nudge development and eld experiment.
JSJ: data analysis.
1. WHO. (2009). On Hand Hygiene in Health Care First Global
Patient Safety Challenge Clean Care is Safer Care.
World Health, 30(1), 270. doi:10.1086/600379.
2. Boyce, J. M., & Pittet, D. (2002). Guideline for hand
hygiene in health-care settings: recommendations of
3 of 4
Amount of visitors using hand sanitizer (%)
Fig. 3 Results from the eld experiment.
Nudging Hospital Visitors' Hand Hygiene Compliance
iNudgeyou © 2016
the Healthcare Infection Control Practices Advisory
Committee and the HICPAC/SHEA/APIC/IDSA Hand
Hygiene Task Force. American journal of infection
control, 30(8), S1-S46.
3. Hansen, P. G., & Jespersen, A. M. (2013). Nudge and the
manipulation of choice: A framework for the responsible
use of the nudge approach to behaviour change in
public policy. Eur. J. Risk Reg., 3.
4. Pedersen, K. M., & Kolmos, H. J. (2007). Hospitalsinfektioner
- en samfundsøkonomisk udfordring. Ugeskrift For
Læger, (November), 4135–4138.
5. Jepsen, O. B. (2000). Hvad Koster Sygehus-infektioner?
CAS-NYT, Copenhagen: Statens Serum Institut, (85).
6. Boyce, J., & Pittet, D. (2002). Guideline for hand hygiene
in healthcare settings. Journal of the American
College of Surgeons, 30(8), 1–46. doi:10.1016/j.
7. Statens Serum Institut. (2015). Håndhygiejne. Retrieved
February 10, 2016, from
Generelle Infektionshygiejniske Retningslinjer/
8. Birnbach, D. J., Nevo, I., Barnes, S., Fitzpatrick, M., Rosen,
L. F., Everett-Thomas, R., ... & Arheart, K. L. (2012).
Do hospital visitors wash their hands? Assessing the
use of alcohol-based hand sanitizer in a hospital lobby.
American journal of infection control, 40(4), 340-343.
9. Hansen, P. G., Skov, L. R., & Skov, K. L. (2016). Making
Healthy Choices Easier: Regulation versus Nudging.
Annual review of public health, (0).
10. Kuniecki, M., Pilarczyk, J., & Wichary, S. (2015). The color
red attracts attention in an emotional context. An ERP
study. Frontiers in human neuroscience, 9.
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... 6 Increasing ease of access: These interventions are related to the repositioning and improving the accessibility of hand sanitiser gel to the public in combination with the use of messages. A total of 2 studies used this approach where they placed floor stands with hand sanitiser gel using messages at key locations of hospitals (Aarestrup et al., 2016;Mobekk & Stokke, 2020). ...
... Seven of the fifteen studies (Aarestrup et al., 2016;Botta et al., 2008;Dreibelbis et al., 2016;Grover et al., 2018;King et al., 2016;Mobekk & Stokke, 2020;Wichaidit et al., 2020) used direct observations to collect their data that varied between each study. For example, some of them concentrated solely on whether people used hand sanitiser or not or whether hands were washed with soap, or the length of hand-washing and whether individuals washed both hands. ...
... Two of the studies reported a small to moderate effect size (Blackwell, 2018) and a small effect size (Gaube et al., 2020), respectively. Overall, the statistically significant relative increase ranged from 6.4% (Judah et al., 2009) to 2133.3% (Aarestrup et al., 2016) over the baseline rates. ...
The COVID-19 pandemic has posed the greatest threat to global health over the last three years. Due to the temporary shortage of appropriate vaccines, a systematic change in human behaviour is necessary to keep the spread of the virus under control, increasing the quality of basic hygiene practices, such as systematic hand hygiene. Nudges are increasingly used in public health interventions to promote critical preventive hygiene behaviours. This review aimed to investigate the effect and the characteristics of nudges on hand hygiene, as a COVID-19 preventive measure. We systematically reviewed the relevant literature from January 2008 to November 2020. A total of 15 articles met the inclusion criteria. The findings of this review showed that most of the nudging interventions had a positive effect on hand hygiene. Nudges should be included in the existing and future public health interventions to prevent the spread of COVID-19 and future pandemics, rather than being an alternative and unconventional tool for public health policies.
... [10] and [11] , far less has been done in order to maintain high levels of HHC among visitors. This may explain the low levels of visitor HHC, e.g., 0.52% [12] , 3% [13] , 7% [14] , reported in the limited literature on this issue. In fact, despite visitors playing a substantial part of hospital activity, only these three experiments aimed at increasing visitor HHC have, to our knowledge, been published. ...
... In one experiment, an increase in HHC from 0.52% to 11.67% was obtained by merely placing a free-standing alcohol-based hand sanitiser (AHS) in front of a security desk with a sign mandating all visitors to use AHS [12] . Another experiment increased HHC amongst visitors from 3% to 67% by placing an AHS in front of the entrance of a hospital section with a sign saying "Here we use HAND DISINFECTANT in order to protect your relative" [13] . A third experiment replicating [13] found an increase from 7% to 46% in visitors HHC in terms of using the AHS [14] . ...
... Another experiment increased HHC amongst visitors from 3% to 67% by placing an AHS in front of the entrance of a hospital section with a sign saying "Here we use HAND DISINFECTANT in order to protect your relative" [13] . A third experiment replicating [13] found an increase from 7% to 46% in visitors HHC in terms of using the AHS [14] . ...
Full-text available
Background Hospital-care-associated infections (HCAIs) represent the most frequent adverse event during care delivery affecting hundreds of millions of patients around the world. Implementing and ensuring conformity to standard precautions, particularly best hand hygiene practices, is regarded as one of the most important and cheapest strategies for preventing HCAIs. However, despite consistent efforts at increasing conformity to standard hand hygiene practices at hospitals, research has repeatedly documented low conformity levels amongst staff, patients and visitors alike. Aim The behavioural sciences have documented the potential of adjusting seemingly irrelevant contextual features in order to ‘nudge’ people to conform to desirable behaviours such as hand hygiene compliance (HHC). In this field experiment we investigate the effect on HHC amongst visitors upon entry of a hospital by varying such features. Methods Over 50 days, we observed the HHC of a total of 46,435 hospital visitors upon their entry to the hospital in a field experimental design covering eight variations over the salience, placement and assertion of the hand sanitiser in the foyer, including the presence of the yearly national HHC campaign and a follow up during the COVID-19 pandemic. Findings Our experiment found that varying seemingly irrelevant features increased HHC from a baseline of 0.4% to 19.7% (47.6% during COVID-19). The experiment also found that the national HHC-campaign had no direct statistically significant effect on HHC. Conclusion Varying seemingly irrelevant contextual features provides an effective, generic, cheap and easy to scale approach to increasing HHC relative to sanitising one’s hands at hospitals.
... 12 The application of behavioral nudges has proven efficacious in increasing desired hand hygiene behaviors in various settings. [13][14][15][16] Previous studies in the hospital context found that installing alcohol-based hand hygiene product dispensers together with behavioral nudges improved hand hygiene behaviors. In a hospital setting, Caris et al., designed posters based on a literature review and cross-sectional survey examining health care providers' responses to the posters, then installed them next to the study dispensers, and found that the proposed nudges increased the use of alcohol-based hand rub next to the dispensers. ...
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Objective: To describe the probability of appropriate hand hygiene behaviors among outpatients and visitors at a primary care unit before and after installation of additionally strategically placed hand rub dispensers and empirically-designed behavioral nudges. Material and Methods: We conducted a quasi-experimental study at a suburban primary care unit in southern Thailand. The intervention consisted of included installation of hand rub dispensers and attachment of behavioral nudges. We designed the behavioral nudges using qualitative data from a focus-group discussion with local residents, who identified disgust and normative expectations from children as the main behavioral drivers for following appropriate hand hygiene behaviors. We then conducted surreptitious observations of hand hygiene behaviors among outpatients and visitors before intervention delivery during Wave 1 and Wave 2 of the pandemic (Phase 1 and Phase 2, respectively), after installation of the hand gel dispensers alone (Phase 3), and after attaching behavioral nudge signs to the dispensers (Phase 4). Results: The probability of appropriate hand hygiene behavior increased from 0.6 percent in Phase 1 to 13.5 percent in Phase 4. However, the increase was statistically significant only from Phase 2 to Phase 3 in the zones where the dispensers were located (adjusted odds ratio 10.58; 95% confidence interval 1.95, 57.24). Conclusion: The probability of appropriate hand hygiene behavior after installation of the dispensers was significantly higher than at pre-intervention, but the difference in appropriate hand hygiene before and after attachment of the nudges to the dispensers was not statistically significant. The study findings could nonetheless contribute empirical evidence on observed changes in hand hygiene behaviors in a primary care setting.
... In the control condition, the alcohol dispenser at the entrance was placed at its original location in the corner of the entrance hall. In the action inference nudging condition, the dispenser was placed closer to the entrance door and there was a red sign next to the dispenser indicating: 'please disinfect hands', according with often used nudging interventions 57 . The goal inference nudging condition was identical to the action inference nudging condition except that the information on the sign was replaced with the information: 'Disinfecting hands saves life's. ...
Full-text available
Effective behavioral interventions are essential to address urgent societal challenges. Over the past decade, nudging interventions (i.e., arranging the environment to promote adaptive behavioral choices) have surged in popularity. Importantly, effective application of the nudging approach requires clear guiding principles with a firm basis in behavioral science. We present a framework for nudging interventions that builds on evidence about the goal-directed inferential processes underlying behavior (i.e., processes that involve context-dependent inferences about goals and the actions available to achieve these goals). We used this framework to develop nudging interventions that target context-relevant cognitive inferences. We examined the effectiveness of these inference nudging interventions for promoting two important types of societal behavior: pro-environmental actions and adherence to COVID-19 guidelines. As predicted, two online studies revealed that inference nudging interventions successfully increased energy conservation (Study 1) as well as social distancing during the COVID-19 crisis (Study 2). A field experiment found that inference nudging interventions increased hand disinfection in a real-life store during the COVID-19 crisis (Study 3). Our findings highlight the importance of applying state-of-the-art insights about the (inferential) determinants of behavior in behavior change interventions. 3
... Despite the fact that direct interventions could greatly effect the behaviour change, the aforementioned methods are straightforward and require a lot of human resources. Hence, some studies utilized nudge theory such as the study of Aarestrup and Moesgaard [1] which proposed a nudging method to improve hand hygiene behaviour for visitors at a healthcare department with a freestanding hand dispenser. Also, Blackwell et al. [6] leveraged nudge methods to increase handwashing up to 15% by using smiley face signs on the mirrors above sinks and arrow-shaped stickers directed towards sinks at public restrooms. ...
... Strategies based on the EAST principle and other behavioral science principles have been well developed and successfully implemented in many countries (such as the United States and England) to increase participation in health-protective behaviors, such as handwashing and influenza vaccination. 17,[28][29][30] What is more, China's COVID strategies are consistent with the COM-B model of behavior change (which has been empirically tested across different cultures) 21 in that they aim to reduce the physical, financial, and mental barriers to engaging in health-protective behaviors; enhance people's capabilities and motivations for taking those actions; and create opportunities to engage in the actions. More generally, the strategies are used in coordination with other COVIDfighting measures rather than in isolation, which reduces the implementation costs and increases the synergistic effects of different public health interventions in a pandemic emergency. ...
Full-text available
Although China’s central and local governments do not have behavioral insights teams, they nonetheless incorporated strategies consistent with behavioral science research when they instituted plans to contain the COVID-19 pandemic. They made it easy for the public to implement health-protective behaviors; eliminated financial barriers to obtaining treatment; set the most stringent protocols as the default to protect health care professionals; simplified decisionmaking about which groups of people needed to self-isolate (thereby enhancing the efficiency of infection-control programs); and provided timely, tailored mental health services to those in need of psychological assistance. Adopting similar practices might help other countries contain the COVID-19 pandemic and enhance future pandemic preparedness and resiliency.
Full-text available
Surveys based on self-reported hygiene relevant routine behaviours have played a crucial role in policy responses to the COVID-19 pandemic. In this article, using anchoring to test validity in a randomised controlled survey experiment during the COVID-19 pandemic, we demonstrate that asking people to self-report on the frequency of routine behaviours are prone to significant measurement error and systematic bias. Specifically, we find that participants across age, gender and political allegiance report higher (lower) frequencies of COVID-19 relevant behaviours when provided with a higher (lower) anchor. The results confirm that such self-reports should not be regarded as behavioural data and should primarily be used to inform policy decisions if better alternatives are not available. To this end, we discuss the use of anchoring as a validity test relative to self-reported behaviours as well as viable alternatives to self-reports when seeking to behaviourally inform policy decisions.
Background: Despite intensified efforts to reduce hospital-onset Clostridium difficile infection (C. difficile; HO-CDI), its clinical and economic impacts continue to worsen. Many institutions have adopted bundled interventions that vary considerably in composition, strength of evidence, and effectiveness. Considerable gaps remain in our knowledge of intervention effectiveness and disease transmission, which hinders HO-CDI prevention. Methods: We developed an agent-based model of C. difficile transmission in a 200-bed adult hospital using studies from the literature, supplemented with primary data collection. The model includes an environmental component and four distinct agent types: patients, visitors, nurses, and physicians. We used the model to evaluate the comparative clinical effectiveness of nine single-interventions and eight multiple-intervention bundles at reducing HO-CDI and asymptomatic C. difficile colonization. Results: Daily cleaning with sporicidal disinfectant and C. difficile screening at admission were the most effective single-intervention strategies, reducing HO-CDI by 68.9% and 35.7%, respectively (both, p<0.001). Combining these interventions into a two-intervention bundle reduced HO-CDI 82.3% and asymptomatic hospital-onset colonization 90.6% (both, p<0.001). Adding patient hand hygiene to healthcare worker hand hygiene reduced HO-CDI rates an additional 7.9%. Visitor hand hygiene and contact precaution interventions did not reduce HO-CDI, compared to baseline. Excluding those strategies, healthcare worker contact precautions was the least effective intervention at reducing hospital-onset colonization and infection. Conclusions: Identifying and managing the vast hospital reservoir of asymptomatic C. difficile by screening and daily cleaning with sporicidal disinfectant are high yield strategies. These findings provide much needed data regarding which interventions to prioritize for optimal C. difficile control.
Full-text available
The color red is known to influence psychological functioning, having both negative (e.g., blood, fire, danger), and positive (e.g., sex, food) connotations. The aim of our study was to assess the attentional capture by red-colored images, and to explore the modulatory role of the emotional valence in this process, as postulated by Elliot and Maier's (2012) color-in-context theory. Participants completed a dot-probe task with each cue comprising two images of equal valence and arousal, one containing a prominent red object and the other an object of different coloration. Reaction times were measured, as well as the event-related lateralizations of the EEG. Modulation of the lateralized components revealed that the color red captured and later holded the attention in both positive and negative conditions, but not in a neutral condition. An overt motor response to the target stimulus was affected mainly by attention lingering over the visual field where the red cue had been flashed. However, a weak influence of the valence could still be detected in reaction times. Therefore, red seems to guide attention, specifically in emotionally-valenced circumstances, indicating that an emotional context can alter color's impact both on attention and motor behavior.
Full-text available
In Nudge (2008) Richard Thaler and Cass Sunstein suggested that public policy-makers arrange decision-making contexts in ways to promote behaviour change in the interest of individual citizens as well as that of society. However, in the public sphere and Academia alike widespread discussions have appeared concerning the public acceptability of nudge-based behavioural policy. Thaler and Sunstein's own position is that the anti-nudge posi-tion is a literal non-starter, because citizens are always influenced by the decision making context anyway, and nudging is liberty preserving and acceptable if guided by Libertarian Paternalism and Rawls' publicity principle. A persistent and central tenet in the criticism disputing the acceptability of the approach is that nudging works by manipulating citizens' choices. In this paper, we argue that both lines of argumentation are seriously flawed. We show how the anti-nudge position is not a literal non-starter due to the responsibilities that accrue on policy-makers by the intentional intervention in citizens' life, how nudging is not essentially liberty preserving and why the approach is not necessarily acceptable even if satisfying Rawls' publicity principle. We then use the psychological dual process theory underlying the approach as well as an epistemic transparency criterion identified by Thaler and Sunstein themselves to show that nudging is not necessarily about "manipulation", nor necessarily about influencing "choice". The result is a framework identifying four types of nudges that may be used to provide a central component for more nuanced normative con-siderations as well as a basis for policy recommendations.
Full-text available
Reports regarding hand hygiene compliance (HHC) among hospital visitors are limited. Although there is an implicit assumption that the availability of alcohol-based hand sanitizer (AHS) promotes visitor HHC, the degree of AHS use by visitors remains unclear. To assess AHS use, we observed visitor HHC and how it is affected by visual cues in a private university hospital. Using an observational controlled study, we tested 3 interventions: a desk sign mandating all visitors to use AHS, a free-standing AHS dispenser directly in front of a security desk, and a combination of a freestanding AHS dispenser and a sign. HHC was 0.52% at baseline and did not improve significantly when the desk sign was provided as a cue 0.67% (P = .753). However, HHC did improve significantly with use of the freestanding AHS dispenser (9.33%) and the sign and dispenser combination (11.67%) (P < .001 for all comparisons of dispenser alone and sign and dispenser with baseline and sign alone). The degree of improvement with the sign and dispenser combination over the dispenser was not statistically significant. Hospital visitors represent an important factor in infection prevention. A coordinated effort is needed to increase visitor HHC, including an evaluation of the AHS placement, education of visitors on the importance of HHC, and evaluation of corresponding changes in hand hygiene behavior.
Hospitalsinfektioner -en samfundsøkonomisk udfordring
  • K M Pedersen
  • H J Kolmos
Pedersen, K. M., & Kolmos, H. J. (2007). Hospitalsinfektioner -en samfundsøkonomisk udfordring. Ugeskrift For Laeger, (November), 4135-4138.
Hvad Koster Sygehus-infektioner?
  • O B Jepsen
Jepsen, O. B. (2000). Hvad Koster Sygehus-infektioner? CAS-NYT, Copenhagen: Statens Serum Institut, (85).
Making Healthy Choices Easier: Regulation versus Nudging. Annual review of public health
  • P G Hansen
  • L R Skov
  • K L Skov
Hansen, P. G., Skov, L. R., & Skov, K. L. (2016). Making Healthy Choices Easier: Regulation versus Nudging. Annual review of public health, (0).