A field study on watching eyes and hand hygiene compliance in a public restroom

Abstract

Humans modify their behavior in a socially desirable way when being watched by others. We applied this basic idea to hand hygiene compliance, a behavior that is crucial for preventing germ transmission and successive infections in many settings. Building on the assumption that hand hygiene behavior is socially desirable, we assume that individuals show stronger hand hygiene compliance when being watched. In a field study in a women's public restroom (N = 354), we exposed individuals to a message advising that hand-washing protects against the spread of pathogens. In the experimental condition, stylized human watching eyes were presented above the message. In the control condition, three stars were presented. Analysis revealed a significantly higher percentage of hand hygiene compliance in the watching eyes condition (83.3%) compared to the control condition (71.9%; odds ratio: 1.95, p = .01). The applied value for employers and public institutions is discussed.

Full text

ORIGINAL ARTICLE
A field study on watching eyes and hand hygiene compliance
in a public restroom
Stefan Pfattheicher
1
|
Christoph Strauch
1
|
Svenja Diefenbacher
1
|
Robert Schnuerch
2
1
Ulm University
2
University of Bonn
Correspondence
Stefan Pfattheicher, Ulm University,
Abteilung Sozialpsychologie, 89069 Ulm,
Germany.
Email: stefan.pfattheicher@uni-ulm.de
Abstract
Humans modify their behavior in a socially desirable way when being watched by others. We
applied this basic idea to hand hygiene compliance, a behavior that is crucial for preventing germ
transmission and successive infections in many settings. Building on the assumption that hand
hygiene behavior is socially desirable, we assume that individuals show stronger hand hygiene
compliance when being watched. In a field study in a women’s public restroom (N5354), we
exposed individuals to a message advising that hand-washing protects against the spread of patho-
gens. In the experimental condition, stylized human watching eyes were presented above the
message. In the control condition, three stars were presented. Analysis revealed a significantly
higher percentage of hand hygiene compliance in the watching eyes condition (83.3%) compared
to the control condition (71.9%; odds ratio: 1.95, p5.01). The applied value for employers and
public institutions is discussed.
1
|
INTRODUCTION
All over the world, hand hygiene
1
is one of the most important means
to prevent the transmission of pathogens and thereby reduce infec-
tions in professional contexts like the healthcare environment, as well
as in home or community settings (e.g., Aiello & Larson, 2002;
Bloomfield, Aiello, Cookson, O’Boyle, & Larson, 2007; Sax et al., 2007;
World Health Organization, 2009). In developing countries, personal
hand hygiene plays a crucial role in the prevention of life-threatening
diseases such as diarrhea and is regarded as one of the most cost-
effective preemptive measures (Bartram & Cairncross, 2010; Borghi,
Guinness, Ouedraogo, & Curtis, 2002; World Health Organization,
2009). In wealthy countries, insufficient personal hand hygiene might
be less life-threatening; nevertheless, it can contribute to elevated
infection rates, particularly in pandemic situations (Aiello & Larson,
2002; Curtis & Cairncross, 2003). In this regard, hand hygiene can save
more than a million people yearly from diarrheal diseases and can
prevent viral infections like influenza (Curtis & Cairncross, 2003;
Moyad & Robinson, 2008).
In addition to home and community settings, adequate hand
hygiene is crucial and even legally regulated in several professional
contexts such as the food processing industries and the healthcare
sector (Allegranzi & Pittet, 2009; Kampf, L€
offler, & Gastmeier, 2009;
Medeiros, Cavalli, Salay, & Proença, 2011; Murphy, DiPietro, Kock, &
Lee, 2011; World Health Organization, 2009). In hospitals, hand
hygiene is particularly relevant with respect to patient safety, as it rep-
resents an effective way to prevent hospital-acquired infections among
patients, a most vulnerable group of individuals, including infections
with multi-drug resistant organisms such as MRSA (Allegranzi & Pittet,
2009; Backman, Zoutman, & Marck, 2008; Ducel, Fabry, & Nicolle,
2002; Kampf, L€
offler, & Gastmeier, 2009; World Health Organization,
2009). Moreover, childcare centers and schools are receiving special
attention given their double role as institutions that directly and
indirectly interconnect a large number of people and as early-in-life
providers of basic education on hand hygiene (Azor-Martínez et al.,
2014; Meadows & Le Saux, 2004; Wang, Lapinski, Quilliam, Jaykus, &
Fraser, 2017). Overall, hand hygiene is an effective strategy for
preventing diseases and contributes to better health in a vast variety of
contexts (Allegranzi & Pittet, 2009).
1
In the present contribution, hand hygiene is used to summarize different
hand hygiene procedures, namely washing hands with plain soap and water
as well as hand disinfection using antimicrobial agents such as alcohol hand
rubs (Diefenbacher, Siegel, & Keller, 2016; World Health Organization,
2009). In different settings, different hand hygiene procedures are required
in order to perform optimal hand hygiene (e.g., at home vs. in hospitals).
J Appl Soc Psychol.2018;1–7. wileyonlinelibrary.com/journal/jasp V
C2018 Wiley Periodicals, Inc.
|
1
Received: 9 August 2017
|
Revised: 3 December 2017
|
Accepted: 11 January 2018
DOI: 10.1111/jasp.12501

All of the above-mentioned hand hygiene-relevant settings differ
in several regards: for example, in the frequency of situations in which
hand hygiene is recommended; in the risk of negative outcomes when
hand hygiene is not performed in those situations; or, in the scope and
severity of the potential negative outcomes. A commonality of these
different settings, however, is the lack of compliance with hand
hygiene recommendations. In private settings, a typical situation rec-
ommended for hand hygiene is after toilet use (Bloomfield et al., 2007;
Nicolle, 2007). Judah and colleagues (2010), for example, report that a
quarter of adult commuters sampled in buses and trains in the
United Kingdom had fecal bacteria on their hands. Other studies
(e.g., Anderson et al., 2008; Cardinale Lagomarsino et al., 2017; Monk-
Turner et al., 2005; Munger & Harris 1989; Nalbone, Lee, Suroviak, &
Lannon, 2005) directly assessed hand hygiene after toilet use in public
restrooms and found largely varying, but frequently suboptimal
compliance rates between 30% and 90% for different populations
(e.g., convenience samples of students or employees at their work
place, male, female, or samples in different regions).
2
Studies on hand
hygiene practices of food workers reported poor compliance with offi-
cial hand hygiene recommendations during food production in 31% of
catering businesses (Clayton & Griffith, 2004) and 27% in restaurants
(Green et al., 2006). A smaller study reported a compliance rate as low
as 7% during food production in restaurants (Strohbehn, Sneed, Paez,
&Meyer,2008).
The best studied hand hygiene context by far is the healthcare sec-
tor, specifically hospitals, where infections that patients might acquire
during their stay are a major concern (Allegranzi & Pittet, 2009; Kampf,
L€
offler, & Gastmeier, 2009; World Health Organization, 2009). None-
theless, compliance with hand hygiene recommendations is still alarm-
ingly low. The mean compliance rate established by a systematic
review of 96 original studies is reported as low as 40% (Erasmus et al.,
2010).
As a consequence of the special importance of hand hygiene and
low compliance in the same, it is crucial to identify methods that
enhance hand hygiene compliance (Naikoba & Hayward, 2001). In par-
ticular, research should focus on easily applicable low-cost methods:
Small interventions could represent a low threshold for companies and
institutions. If successful, such interventions could increase health, in
the case of employers, save money due to fewer employee sick days,
decrease infection-related absenteeism in schools, and increase patient
safety in hospitals or other healthcare institutions. In sum, strategies
toward increasing hand hygiene are urgently needed and should be in
the focus of research. The present investigation takes one step in this
direction; specifically, we tested whether a simple cue of being
watched, that is, the presentation of stylized watching eyes, increases
hand hygiene compliance after using a public restroom. In this way, we
tested whether a low-cost method (i.e., the simple presentation of
stylized watching eyes) can improve hand hygiene. This approach might
not only serve applied value for companies, public institution, and
people’s health per se, but also contributes to our basic understanding
about how hand hygiene can be improved. As outlined in detail to
follow, we argue that (subtle) social presence offers this potential.
1.1
|
Watching eyes and socially desirable behavior
There is long-standing, striking evidence that individuals modify their
behavior when other individuals are present (Markus, 1978; Zajonc,
Heingartner, & Herman, 1969). In particular, individuals act in a socially
desirable way when being watched by others (Leary & Kowalski, 1990;
Van Bommel, van Prooijen, Elffers, & van Lange, 2014). It appears that
people not only modify their behavior when other individuals are
present, but also when mere reminders of being observed (i.e., human
watching eyes) are present in the environment (Haley & Fessler, 2005).
In recent years, a growing number of researchers have shown that cues
of being watched reduce socially undesirable behavior such as bicycle
theft (Nettle, Nott, Bateson, & No€
e, 2012) or littering (Ernest-Jones,
Nettle, & Bateson, 2011). Similarly, cues of being watched increase
socially desirable behavior such as cooperation (Bateson, Nettle, &
Roberts, 2006) and donations to charity given relatively few other
people were present (Ekstr€
om, 2012). Yet we want to point to several
published null effects in the study of cues of being watched
(Northover, Pedersen, Cohen, & Andrews, 2017). We discuss this issue
in detail in the Discussion section.
In the present contribution, we argue that, due to its important
role in the prevention of disease-spreading, hand hygiene reflects a
socially desirable and expected behavior (Aunger et al., 2016). On this
basis, we assume that individuals show stronger hand hygiene
compliance when being watched. In fact, past research shows that an
observer present in a public restroom increases the number of people
who wash their hands after using the restroom (Munger & Harris,
1989). This finding could be replicated in other public restrooms
(Cardinale Lagomarsino et al., 2017; Edwards et al., 2002; Nalbone
et al., 2005) and for hand hygiene compliance in hospitals (Eckmanns,
Bessert, Behnke, Gastmeier, & R€
uden, 2006; Maury, Moussa, Lakermi,
Barbut, & Offenstadt, 2006).
Recent studies have explored whether the presentation of watch-
ing eyes can be applied to increase hand hygiene behavior. Beyfus
et al. (2016; see also King et al., 2016) demonstrate increased compli-
ance with hand hygiene recommendations in a hospital when watching
eyes are placed next to an alcohol foam dispenser compared to when
no stimulus is presented. However, there were two notable disadvan-
tages in that study: First, the image not only showed eyes but the eyes
of a recognizable leader at the institution where the study took place.
Second, the eyes pinned above the dispensers could be interpreted as
angry. Therefore, the findings might not reflect the influence of a
simple depiction of watching eyes. Instead, they could be driven by the
participants’fear of being caught—by someone in leadership—violating
the hand hygiene instruction and/or the apparent aggressiveness of
the eyes. Interestingly, a similar study in the hospital context showed
that angry watching eyes do not significantly increase hand hygiene
2
A huge portion of variation in reported compliance rates might be caused
by (a) different operationalizations, that is, what specific behavior is consid-
ered in the study (e.g., washing with or without soap; disinfection yes or
no), and (b) the facilities that are considered (i.e., commodes and/or urinals
which can differ in perceived contamination of hands; Berry, Mitteer, &
Fournier, 2015).
2
|
PFATTHEICHER ET AL.

behavior (Bolton, Rivas, Prachar, & Jones, 2015). Overall, research is
needed to enhance knowledge on the possible effect of watching eyes
on hand hygiene behavior. In the study reported below, we address
this issue and examined whether (neutral) watching eyes increase hand
hygiene compliance. The study took place in a women’spublic
restroom.
2
|
STUDY
2.1
|
Methods
2.1.1
|
Procedure and assessments
A field study was set up to assess the impact of watching eyes on
hand-washing compliance after using a public restroom. The study took
place at a central public restroom on a campus at a German university.
The study was conducted in full accordance with the Ethical Guidelines
of the German Association of Psychologists (DGPs) and the American
Psychological Association (APA). No personal information was
assessed; participants remained completely anonymous and were not
identified in any regard during the study process. Moreover, by the
time the data were acquired in June 2017, it was also not customary at
Ulm University, nor at most other German universities, to seek ethics
approval for simple, noninvasive field studies.
Hand hygiene compliance was defined as washing hands with
soap. Data on whether individuals washed their hands with soap was
collected with a soap dispenser provided by the company Ophardt
Hygiene Technologies, Inc.
3
The dispenser set timestamps for each
use. In addition, the times individuals entered and left the restroom
were recorded by one hidden (female) observer situated about 15
meters away.
4
The recorded times of entering and leaving the restroom
and the data from the soap dispenser were matched to determine who
used the dispenser. Whether or not people used soap to wash their
hands served as the binary dependent variable. In addition, we
recorded (a) whether at least one other person was also present during
the time individuals were in the restroom (control group583.3%,
watching eyes 578.8%, n.s.), and (b) the time, in minutes, that individu-
als spent in the restroom (control group M53.46, SE5.09; watching
eyes M53.22, SE5.08, t(352) 51.93, p5.05, Cohen’sd50.21).
5
2.1.2
|
Watching eyes
Two posters were changed every 1–2 hr, reflecting two conditions (see
Figure 1). In the control condition (n5144), a poster carrying a
message of advice on hand hygiene and a distractor (three stars) was
displayed directly at the sink. The message read “Hände verbreiten
Krankheitserreger. Richtig waschen sch€
utzt.”(Hands spread pathogenic
germs. Hand-washing protects). In the experimental condition
(n5210), the stars were replaced by a pictogram of neutral eyes look-
ing straight ahead, taken from Keller and Pfattheicher (2011; see also
Pfattheicher & Keller, 2015). The message of advice was therefore
present in both conditions, but the presence of the watching eyes
versus stars was varied. Both posters were the size of an ISO 216
paper sheet (210 mm 3297 mm). Posters were changed only when no
individuals were in the restrooms and the procedure took only a few
seconds. We used the pictogram of watching eyes because they were
relatively neutral, that is, more parsimonious regarding the information
that is salient in the situation. Accordingly, possible confounding factors
that may come along with other (eye) manipulations (e.g., attractive-
ness, emotion) can be excluded. The applied eyes were tested
previously in a study by Pfattheicher and Keller (2015). They found
that these eyes reliably increase a sense of being watched.
2.1.3
|
Sample
Using G*Power (Faul, Erdfelder, Buchner, & Lang, 2009), a power anal-
ysis was conducted for a one-tailed z-test for a single binominal regres-
sion coefficient in a logistic regression. Power was set to .80 (Cohen,
1992) and a medium effect (odds ratio 52.15; Rosenthal, 1996) was
assumed which would correspond to an increase of hand hygiene com-
pliance from 65% to 80% caused by watching eyes. We went for a
medium effect to detect an effect that is of relevant size. This power
analysis revealed a required sample size of N5220 to detect a signifi-
cant effect (alpha level of .05) given there actually is an effect. Data
from 354 individuals between June 20 and 27, 2017, could be
collected. Due to the fact that the experimenter was female while a
FIGURE 1 The posters pinned in the restroom: Watching eyes (left) and the three stars (right) with the message about hand washing. The
message (in German) says “Hands spread pathogens. Hand washing protects”
3
We could have used a dispenser from another company as well. To be
transparent, we mentioned that the dispenser is from Ophardt Hygiene
Technologies, Inc.
4
The observer only entered the restroom to change the watching eye pic-
ture (experimental condition) and the three stars (control condition). The
study took place in the main building of the university; there are typically
other people also present outside the restroom walking by or sitting there.
That said, the observer was probably not considered an “observer”but as a
person just sitting there.
5
As reported in detail below, watching eyes increased hand hygiene compli-
ance. Controlling for time spent and whether other people were present
even strengthened the effect of watching eyes on hand hygiene behavior.
PFATTHEICHER ET AL.
|
3

regular change of posters in the restrooms was necessary, the study
took place only in the women’s restroom. Data of the study are avail-
able on the Open Science Framework (see https://osf.io/5dkf3). We
used SPSS Statistics 24 (IBM Corp., Armonk/USA) to run the analyses.
As we had a binary variable (hand hygiene yes/no), we ran logistic
regression analyses. For testing interactions, we used the PROCESS
macro provided by Hayes (2013).
3
|
RESULTS
Overall, 76.6% of the individuals used the soap dispenser. Using logistic
regression analysis, whether individuals used the soap dispenser
(1 5yes, 0 5no) was regressed on the experimental condition
(1 5watching eyes condition, 0 5control condition). This analysis
revealed a significant effect of the experimental condition (B5.67,
SE 5.27, p5.01, odds ratio 51.95, Nagelkerke R
2
5.03, v
2
56.41).
Specifically, analysis suggests that individuals used the soap dispenser
more often in the watching eyes condition (83.3%) compared to the
control condition (71.9%).
To provide convergent evidence that social presence increased
hand hygiene compliance (see also Edwards et al., 2002; Munger &
Harris, 1989), we analyzed whether the presence of at least one other
person during the time individuals were in the restroom (1 5yes,
05no) also increased hand hygiene compliance. This was the case
(B5.74, SE 5.29, p5.01, odds ratio 52.10, Nagelkerke R
2
5.03,
v
2
56.14). Specifically, when at least one person was present, individu-
als used the soap dispenser more often (79.4%) compared to when
they were alone (64.7%). This finding is of high importance as it pro-
vides convergent and independent validity: either subtle social pres-
ence (i.e., watching eyes) or real social presence increased hand
hygiene behavior. This speaks to the validity of the entire study. In
addition, we tested whether the effect of the experimental condition
(i.e., the presence of watching eyes) depended on the presence of other
people in the restroom (see Ernest-Jones et al., 2011; Powell, Roberts,
Nettle, & Fusani, 2012). No significant interaction was found (p5.35).
Next, we (exploratively) examined whether the effect of watching
eyes depended on the time people spent in the restroom. To test this
notion, whether individuals used the soap dispenser was regressed on
the experimental condition (this time contrast coded to allow interpre-
tation of main effects, 10.5 5watching eyes condition, 20.5 5control
condition; cf. Hayes, 2013), the time spent in the restroom (centered to
the mean), as well as their interaction (overall statistics of this model:
Nagelkerke R
2
5.11, v
2
525.60, p<.001). Analysis revealed a signifi-
cant main effect of the experimental condition (i.e., the presence of
watching eyes; B5.56, SE 5.28, p5.05, Odds ratio 51.75) and a sig-
nificant main effect of the time spent in the restroom (B5.32, SE5.15,
p5.04, Odds ratio 51.38). The latter main effect indicates that the
probability of hand washing increased the longer individuals stayed in
the restroom. Most importantly, the two main effects were qualified by
a significant interaction (B52.83, SE 5.31, p<.01, Odds ratio 5.43).
The pattern of the interaction is displayed in Figure 2.
Decomposing the interaction (Aiken & West, 1991; Hayes, 2013),
watching eyes increased hand hygiene compliance only when individ-
uals spent a relatively short period (1 SD below the mean; i.e., about 2
min) in the restroom (B51.52, SE 5.41, p<.001, Odds ratio 54.57).
When individuals spent a relatively long period (1 SD above the
mean, i.e., about 4.5 min) in the restroom, watching eyes did not
significantly increase hand hygiene compliance (B52.40, SE 5.50,
p5.42, Odds ratio 5.67). That is to say, individuals already had a rel-
atively high hand hygiene compliance when staying a relatively long
time in the restroom. However, when staying a relatively short time
in the restroom, hand hygiene compliance was lower and could be
significantly increased by watching eyes. These interesting findings
are further discussed below.
4
|
DISCUSSION
The present research deals with a question that is important for
humans’health: How can we increase hand hygiene compliance? Build-
ing on (a) past research showing that watching eyes increase socially
desirable and expected behavior (e.g., Ekstr€
om, 2012; Powell et al.,
2012), and (b) the assumption that hand washing after using the toilet
is socially desirable and expected (Aunger et al., 2016), we have
assumed that the presentation of watching eyes has the potential to
increase hand hygiene compliance. In line with this hypothesis, we
show a significant increase of hand hygiene compliance when watching
eyes were presented in a women’s restroom, as compared with a
neutral control condition.
The present work has several implications and contributes to the
existing literature in a meaningful way. First, we extend previous
research on watching eyes and hand hygiene behavior. Beyfus and col-
leagues (2016) as well as Bolton et al. (2015) tested the effect of angry
watching eyes on individuals’hand hygiene; in addition, Beyfus and col-
leagues (2016) used the eyes of a recognizable leader at the institution
where the study took place. In our study, we eliminated these interfer-
ing third variables by using simple, neutral-looking eyes and were able
to demonstrate their positive effect on hand hygiene compliance. Thus,
FIGURE 2 Probability of using the soap dispenser as a function
of the experimental condition and the time spent in the
restroom
4
|
PFATTHEICHER ET AL.

we can conclude that the mere presence of watching eyes has the
potential to increase hand hygiene compliance.
6
Second, amidst recent concerns about reproducibility in psycholog-
ical science (Open Science Collaboration, 2015), replications should be
of particular interest to the field (Brandt et al., 2014). Indeed, with the
present study we conceptually replicate previous research showing
that the (actual) presence of other people increases hand hygiene com-
pliance (Eckmanns et al., 2006; Edwards et al., 2002; Maury et al.,
2006; Munger & Harris, 1989). In combination with the finding that
watching eyes affect hand-washing behavior, the present research pro-
vides convergent evidence that different forms of social presence can
likely increase hand hygiene compliance.
Third, with the present study, we might also show who increases
hand hygiene compliance when being watched. Taking into account
the time individuals spent in the restroom, we document an effect of
watching eyes only when individuals spend a relatively short period in
the restroom. Remarkably, for these individuals, watching eyes had a
big effect in terms of effect size (Rosenthal, 1996). In contrast, when
individuals spent a relatively long period in the restroom, hand hygiene
compliance was already high and could not be further increased by
watching eyes. We speculate that staying for a longer period in the
restroom is accompanied with defecation rather than urination only. In
these instances, individuals might see a greater necessity to wash their
hands with soap. Given this ceiling effect, watching eyes could not
have an additional impact. We further speculate that staying in the
restroom for a shorter period of time is accompanied with urination
only. In these instances, individuals might see less of a need to wash
their hands with soap, leaving room for watching eyes to increase hand
hygiene compliance.
4.1
|
Limitations and outlook
Since the reported data are the result of a field experiment, limitations
are particularly important to mention. First, we acknowledge that we
cannot draw conclusions about why watching eyes have increased
hand hygiene compliance in the present study. That is, we have not
provided evidence for the psychological process in this field study.
Recent research has accumulated evidence that individuals’avoidance
(rather than approach) system underlies the effect of social influence in
general and watching eyes in particular (Keller & Pfattheicher, 2011;
Pfattheicher, 2015; Pfattheicher & Keller, 2015; Schnuerch &
Pfattheicher, in press; Steinmetz & Pfattheicher, 2017). That is to say,
individuals typically change behavior when being observed not to gain
a positive reputation and to make a good impression in the eyes of
others (i.e., approach) but typically to avoid the violation of social
expectations, social punishment, and a bad reputation. On this basis,
one can argue that the effect of watching eyes on hand hygiene
compliance might be based on individuals’avoidance system, yet we
have no empirical basis for this claim so far.
Second, in the present study, the advice to wash one’s hands was
present in both experimental conditions. Thus, we cannot conclude
whether watching eyes per se increase hand hygiene compliance, or
whether basic advice sets a precondition for watching eyes to operate.
We assume that the message of advice smoothes the way for watching
eyes to increase hand hygiene compliance. With information about the
necessity of hand washing being activated, watching eyes might create
the social expectation that hand washing should be done, leading to
actual hand-washing behavior. Without information about the neces-
sity of hand washing being activated, there is no information available
that can be transformed into social expectations, affecting behavior.
Future investigations could thus add a condition during which only
watching eyes are present to assess the impact of the advice alone and
to enable an estimation of possible interactions.
Also in light of recent meta-analyses and publications showing
weak evidence of a main effect of watching eyes on prosocial behavior
(e.g., Northover et al., 2017; Sparks & Barclay, 2013), it is relevant for
future research to examine preconditions for watching eyes to affect
human behavior (see also Northover et al., 2017; Pfattheicher & Keller,
2015). In the theoretical part of this contribution, we have argued that
watching eyes increase socially desirable behavior. In this regard, we
speculate that hand hygiene is strongly socially desirable; thus, as
shown in the present contribution, watching eyes can increase this
behavior. In contrast, transferring money to an anonymous stranger
could be considered less socially desirable; the lower degree of social
desirability might explain the found null effects with this dependent
variable (Northover et al., 2017). Building on these considerations, a
promising approach for future research would be to manipulate the
degree of social desirability that is inherent in the investigated behavior
and to test whether watching eyes increase prosocial behavior
especially when it is socially desirable.
Third, we want to acknowledge that the study assessed data from
females only and took place at a public restroom on a university cam-
pus. Thus, our conclusions apply to this specific group and this specific
context. The question whether the effect found in the present study is
also found in different places and populations can only be answered in
future research. Given that hand hygiene behavior is likely socially
desirable in different places and populations, we expect that watching
eyes increase hand hygiene behavior in different contexts as well. In
this regard, it seems particularly promising to test the effect of
watching eyes in companies and public institutions. In fact, watching
eyes reflect a low-cost method with the potential to increase hand
hygiene compliance, which in turn might reduce germ transmission; as
such, the application of watching eyes could increase health, save
money for employers due to fewer sick days for employees, decrease
infection-related absenteeism in schools, and increase patient safety in
hospitals or other healthcare institutions. This, however, needs to be
tested in future research.
To conclude, the present contribution shows the potential of
watching eyes to increase hand hygiene compliance. As such, the pres-
ent work opens a new avenue of research for studying hand hygiene
6
By showing that watching eyes can increase hand hygiene behavior we do
not claim that norms are irrelevant (they are indeed highly relevant); we
merely argue that there are different routes to increasing hand hygiene
behavior that do not exclude each other. One way is though norms (and
safety climate and safety culture) and another is through simple nudges like
watching eyes.
PFATTHEICHER ET AL.
|
5

compliance while emphasizing that individuals’behavior can be influ-
enced by simple social nudges.
ORCID
Stefan Pfattheicher http://orcid.org/0000-0002-0161-1570
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How to cite this article: Pfattheicher S, Strauch C, Diefenbacher
S, Schnuerch R. A field study on watching eyes and hand
hygiene compliance in a public restroom. J Appl Soc Psychol.
2018;00:1–7. https://doi.org/10.1111/jasp.12501
PFATTHEICHER ET AL.
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