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Psychological Science
22(12) 1494 –1499
© The Author(s) 2011
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DOI: 10.1177/0956797611419172
http://pss.sagepub.com
In 1847, Ignaz Semmelweis required health care professionals
at the Vienna General Hospital to wash their hands, and death
rates due to childbed fever decreased from 18.3% to 1.3%.
Since then, extensive research has demonstrated that hand
hygiene plays a critical role in preventing the spread of infec-
tions and diseases (Backman, Zoutman, & Marck, 2008). Nev-
ertheless, it is common for health care professionals to wash
their hands less than half as often as recommended, and many
interventions for improving hand hygiene among health care
professionals have proven ineffective (Gawande, 2004;
Whitby et al., 2007). How can psychological science guide the
development of messages to address this pressing problem?
Messages about health and safety are thought to be effec-
tive when they highlight personal risks for the actor. Research-
ers have speculated that health care professionals “are probably
driven to wash their hands by their need to protect themselves
more than [by their need to protect] their patients” (Korniewicz
& El-Masri, 2010, p. 88). According to this line of logic, mes-
sages aimed at health care professionals should emphasize
how hand hygiene protects them personally. Such messages
are believed to activate basic motivations related to survival
and self-protection (Rothman & Salovey, 1997). As Williams
and Noyes (2007) summarized, safety behavior “is dependent
on individuals believing that the risk is likely to affect them,
that it will have serious consequences for them” (p. 21, empha-
sis in original).
However, research on overconfidence has shown that indi-
viduals consistently overestimate their immunity (Dunning,
Heath, & Suls, 2004). This illusion of invulnerability is com-
mon among health care professionals. As two physicians
explained, “I’m a doctor, I’m protected,” and “We doctors
wear magic white coats. We destroy disease. . . . How could it
ever attack us?” (Klitzman, 2006, p. 547).
Overconfidence is likely to be fueled by both motivational
and cognitive processes. First, to maintain a sense of security
while working in hazardous environments, health care profes-
sionals may need to convince themselves that they are pro-
tected. According to research on motivated reasoning (Kunda,
1990) and confirmation biases (Nickerson, 1998), health
care professionals may search for information that seems to
verify their personal safety and may discount information that
Corresponding Author:
Adam M. Grant, University of Pennsylvania, 3620 Locust Walk, Suite 2000
SH/DH, Philadelphia, PA 19104-6370
E-mail: grantad@wharton.upenn.edu
It’s Not All About Me: Motivating Hand
Hygiene Among Health Care Professionals
by Focusing on Patients
Adam M. Grant1 and David A. Hofmann2
1Management Department, The Wharton School, University of Pennsylvania, and
2Kenan-Flagler Business School, University of North Carolina at Chapel Hill
Abstract
Diseases often spread in hospitals because health care professionals fail to wash their hands. Research suggests that to increase
health and safety behaviors, it is important to highlight the personal consequences for the actor. However, because people
(and health care professionals in particular) tend to be overconfident about personal immunity, the most effective messages
about hand hygiene may be those that highlight its consequences for other people. In two field experiments in a hospital, we
compared the effectiveness of signs about hand hygiene that emphasized personal safety (“Hand hygiene prevents you from
catching diseases”) or patient safety (“Hand hygiene prevents patients from catching diseases”).
We assessed hand hygiene by
measuring the amount of soap and hand-sanitizing gel used from dispensers (Experiment 1) and conducting covert, independent
observations of health care professionals’ hand-hygiene behaviors (Experiment 2). Results showed that changing a single word
in messages motivated meaningful changes in behavior: The hand hygiene of health care professionals increased significantly
when they were reminded of the implications for patients but not when they were reminded of the implications for themselves.
Keywords
social influences, motivation, health, cooperation
Received 5/27/11; Revision accepted 7/12/11
Research Report
Hospital Hand Hygiene 1495
suggests they are at risk. Indeed, research has shown that peo-
ple tend to respond defensively to information that poses a
threat to their personal health or safety: People are likely to
scrutinize such messages for flaws rather than accept the infor-
mation they contain (Liberman & Chaiken, 1992).
Second, although health care professionals are frequently
exposed to diseases, they contract relatively few. When they
do get sick, it is not clear that poor hand hygiene is the culprit.
Thus, it may be easy for health care professionals to recall
instances in which they failed to wash their hands without get-
ting sick, but difficult for them to recall episodes in which fail-
ing to wash their hands made them ill. According to research
on the availability heuristic (Tversky & Kahneman, 1974),
because the ease with which an event comes to mind serves as
a cue for its likelihood (Schwarz et al., 1991), health care pro-
fessionals should perceive that failing to wash their hands
poses little personal risk. Consequently, messages emphasiz-
ing the personal consequences of hand hygiene for health care
professionals may fall on deaf ears.
Research on persuasion reveals that for a message to reso-
nate with an audience, it must be relevant to that audience’s
perspective (Cialdini, 2003; Clary & Snyder, 1999; Rothman
& Salovey, 1997). We hypothesized that health care profes-
sionals would be more motivated to wash their hands by mes-
sages highlighting patient consequences than by messages
highlighting personal consequences. Whereas people tend to
overestimate their own invulnerability, for both motivational
and cognitive reasons, they are less susceptible to this bias
when estimating the vulnerability of other people (Dunning
et al., 2004). Moreover, the fact that patients are by definition
a vulnerable population may make their risks salient to health
care professionals, who are trained to err in favor of caution
when treating patients (Gigerenzer, Gaissmaier, Kurz-Milcke,
Schwartz, & Woloshin, 2008).
Thus, messages aimed at health care professionals should
be most effective when they emphasize how hand-hygiene
practices can protect patients’ health rather than personal
health. We tested this hypothesis in two field experiments in a
hospital by subtly manipulating the content of signs about
hand hygiene and testing their influence with unobtrusive
measures (Webb, Campbell, Schwartz, & Sechrest, 1966). To
measure the signs’ effects, we used two strong, complemen-
tary assessment techniques recommended by The Joint
Commission (2009) as part of the Consensus Measurement in
Hand Hygiene project: objective measurements of the use of
hand-hygiene products and independent observations of adher-
ence to safe hand-hygiene practices.
Experiment 1
Method
We compared the effects of signs emphasizing personal conse-
quences, patient consequences, or neither on the hand-hygiene
behaviors of health care professionals in a U.S. hospital. Our
focus on signs was based on evidence that small variations in
the content of messages can produce powerful changes in mind-
sets and behaviors (Cialdini, 2003; Crum & Langer, 2007). We
assessed hand hygiene by measuring the percentage of soap and
hand-sanitizing gel used from dispensers in hospital units; this
technique was both objective and unobtrusive (The Joint Com-
mission, 2009). Our sample comprised 66 dispensers available
for physicians and nurses in the hospital, and we measured the
amount of soap and gel used during 2-week periods before and
after we introduced our signs. To measure baseline product use,
we had an environmental-services team fill the bag in each dis-
penser with soap or gel and weigh each bag 2 weeks later. This
team, which was blind to our hypotheses, then refilled the dis-
pensers before we began the experiment. To minimize demand
characteristics and cross-contamination, we did not inform
employees at the hospital that research was underway.
We randomly assigned one of three signs to each dispenser.
The personal-consequences sign read, “Hand hygiene prevents
you from catching diseases.” The patient-consequences sign
read, “Hand hygiene prevents patients from catching diseases.”
The control sign, which was developed by hospital managers,
read, “Gel in, wash out.” Except for these subtle differences in
wording, the signs were identical. One sign was posted above
each dispenser by a safety professional. After 2 weeks, the
environmental-services team weighed each bag again. Because
the bags were of different sizes, we report our dependent mea-
sure as the percentage by weight of soap or gel used.
Results and discussion
Table 1 reports the mean percentage of soap or gel used from
the dispensers in each condition, before and after the signs
were introduced. A repeated measures analysis of variance on
the amount of hand-hygiene product used showed a significant
interaction between time (pretest, posttest) and condition
Table 1. Mean Percentage (by Weight) of Hand-Hygiene Products Used as a Function of
Condition in Experiment 1
Condition Pretest product usage Posttest product usage
Control (n = 21) 38.24% (24.90) 40.13% (24.43)
Personal consequences (n = 23) 35.49% (28.18) 33.98% (19.65)
Patient consequences (n = 22) 37.25% (36.46) 54.18% (18.33)
Note: Standard deviations are in parentheses.
1496 Grant, Hofmann
(personal consequences, patient consequences, control), F(2,
63) = 3.30, p = .04, η2 = .09, prep = .89. Paired-samples t tests
showed a significant increase from pretest to posttest in the
amount of hand-hygiene product used from dispensers with the
patient-consequences sign (37.25% to 54.18%), t(21) = 2.72,
p = .01, d = 0.59, prep = .96, but not from dispensers with the
personal-consequences sign (35.49% to 33.98%), t(22) = −0.27,
p = .79, or the control sign (38.24% to 40.13%), t(20) = 0.64,
p = .53. Tukey’s multiple comparison test showed no significant
differences between conditions in the pretest use of hand-
hygiene product, but in the posttest, the amount of hand-hygiene
product used from dispensers with the patient-consequences
sign was significantly greater than the amount used from dis-
pensers with the personal-consequences sign (p < .01, d = 1.06,
prep = .97) or the control sign (p < .05, d = 0.65, prep = .89).
Although these results are encouraging, they are subject to
two key limitations. First, health care professionals may have
been influenced by a sign near one dispenser but used hand-
hygiene products from a different dispenser. Second, it is pos-
sible that the effects were influenced either by a small number
of health care professionals who used large quantities of hand-
hygiene products or by patients who gained access to the
dispensers. To address these potential confounds, in Experi-
ment 2, we assigned the personal-consequences and patient-
consequences signs to separate hospital units and asked
experts to directly observe health care professionals’ hand-
hygiene behaviors.
Experiment 2
Method
Nine months after Experiment 1, we conducted a second
experiment in different units of the same hospital, using the
same personal- and patient-consequences signs. We enlisted
three experts—a physician in charge of patient safety, an
infectious-disease specialist, and a lead nurse manager—
to organize hospital units into matched pairs on the basis of
similar types of patients, health conditions, and professional
specialties. The three experts achieved consensus on
four matched pairs of units: pediatric and neonatal intensive
care units (ICUs), cardiac and neurological critical care
units (CCUs), cardiology and chest-pain units, and general-
observation and medical-teaching units. We assigned the
personal-consequences sign to four of the units (pediatric ICU,
cardiac CCU, cardiology, and general observation) and the
patient-consequences sign to the other four units (neonatal
ICU, neurological CCU, chest pain, and medical teaching).
We measured hand hygiene using observations of the
behaviors of health care professionals. For each unit, the
patient-safety team identified one expert observer with profes-
sional training and certifications in nursing. The observers
were blind to our hypotheses and conducted their observations
covertly, thereby minimizing demand characteristics and
reducing the likelihood that the observed health care profes-
sionals would be aware that research was underway and that
their behavior was being tracked. Following the guidelines
recommended by the Consensus Measurement in Hand
Hygiene project team (The Joint Commission, 2009), we
asked the observers to count health care professionals’ oppor-
tunities for hand hygiene and to indicate whether the health
care professional in each instance adhered to safe hand-
hygiene practices. We defined an opportunity for hand hygiene
as occurring before or after contact with a patient. To ensure
that only health care professionals’ behavior was included in
the data, the observers recorded the date of each hand-hygiene
opportunity and the type of practitioner involved. Observers
identified three types of practitioners: nurses (59% of observa-
tions), physicians (17% of observations), and ancillary staff
(technicians, nutritionists, social workers, pharmacists, and
transporters; 24% of observations).
We collected pretest data over a 2-week period, during which
the observers identified 322 hand-hygiene opportunities (the
practitioners adhered to hand-hygiene guidelines in 259 of these
instances). After the pretest, medical-safety professionals posted
the signs in their assigned units. The ratios of signs to patient
beds were equivalent in the two conditions: .80 for units
assigned to the personal-consequences condition (57 signs, 71
beds) and .79 for units assigned to the patient-consequences
condition (69 signs, 87 beds). The observers identified 245
hand-hygiene opportunities during the 2-week posttest period
(the practitioners adhered to hand-hygiene guidelines in 212 of
these instances). We tested whether hand-hygiene adherence
increased on units with the patient-consequences sign but not on
units with the personal-consequences sign.
Results and discussion
Table 2 reports the percentage of instances in which health care
practitioners adhered to safe hand-hygiene practices in each con-
dition, before and after the signs were introduced. A contingency-
table analysis showed that hand-hygiene adherence increased
Table 2. Adherence to Safe Hand-Hygiene Practices as a Function of Condition in
Experiment 2
Condition
Pretest
hand-hygiene adherence
Posttest
hand-hygiene adherence
Personal consequences 80.00% (96/120) 79.71% (55/69)
Patient consequences 80.69% (163/202) 89.20% (157/176)
Hospital Hand Hygiene 1497
significantly on units with the patient-consequences sign
(80.69% to 89.20%), χ2(1, N = 378) = 5.25, p = .02, d = 0.33,
prep = .93. In contrast, hand-hygiene adherence did not change
significantly on units with the personal-consequences sign
(80.00% to 79.71%), χ2(1, N = 189) = 0.04, p = .85. During the
pretest period, the units assigned to the personal- and patient-
consequences conditions did not differ significantly in hand-
hygiene adherence, χ2(1, N = 322) = 0.02, p = .88. However,
during the posttest period, hand-hygiene adherence was signifi-
cantly greater on units with the patient-consequences sign than
on units with the personal-consequences sign, χ2(1, N = 245) =
3.83, p = .05, d = 0.36, prep = .88.
Although the units were matched and then randomly
assigned to condition, we reanalyzed the data to control for
unit; the same pattern of results emerged. To examine whether
the observed effects of the patient-consequences sign were due
to unique characteristics of the high-risk units or of the health
care professionals who worked in such units, we compared the
higher-risk units (ICUs and CCUs) with the lower-risk units.
Binary logistic regression analyses showed no significant
differences between unit types in the effects of the patient-
consequences sign (b = 0.31, SE = 0.62, Wald z = 0.25, p = .62)
or of the personal-consequences sign (b = 0.19, SE = 0.88,
Wald z = 0.05, p = .83); this result suggests that the effects
were robust across units. We also investigated whether the
effects varied by practitioner type (see Table 3). The patient-
consequences sign significantly increased hand hygiene for
physicians, marginally increased it for nurses, and did not affect
the hand-hygiene behavior of ancillary staff. The personal-
consequences sign had no significant effects.
General Discussion
Together, these findings suggest that messages about patient
consequences, rather than personal consequences, can encour-
age hand hygiene among health care professionals. Our results
have important theoretical and practical implications for the
design of persuasive communications about health and safety.
In theoretical terms, whereas research has typically focused on
the effects of highlighting the personal consequences of
health- and safety-related behaviors (Williams & Noyes,
2007), our studies demonstrate the value of highlighting the
consequences of such behaviors for other people. Psycholo-
gists have long recognized that seemingly innocuous situa-
tional forces, such as time pressure, can impede prosocial
behaviors even among good Samaritans with the best of inten-
tions (Darley & Batson, 1973). It is tempting to conclude that
capturing the attention of busy health care professionals to
encourage hand hygiene depends on appealing to their imme-
diate self-interest (Korniewicz & El-Masri, 2010). However,
our research reveals that reminders of prosocial consequences
may have a greater influence on the hand-hygiene behavior of
health care professionals than reminders of personal conse-
quences do (see also Grant, 2008).
In practical terms, the significant effects of our subtle
experimental manipulation on a difficult-to-change dependent
variable have substantial real-world implications (Prentice &
Miller, 1992). Over 2-week periods, the patient-consequences
signs produced an increase of more than 45% in the amount of
hand-hygiene product used per dispenser (Experiment 1) and
an increase of more than 10% in hand-hygiene behavior
among health care professionals before and after contact with
patients (Experiment 2). These results are particularly mean-
ingful given that the few hand-hygiene interventions known to
be successful tend to rely on expensive technologies and large-
scale cultural changes (Pittet et al., 2000; Whitby et al., 2007).
A key limitation of both studies is that they lasted for only
2 weeks. Because the effects of hand-hygiene interventions
are often short-lived (Pittet et al., 2000), an examination of
their sustainability is of critical importance. If they fade
because of habituation and desensitization, researchers should
explore strategies for maintaining novelty, such as rotating
messages or incorporating photos of patients into messages.
Nevertheless, 2 weeks of increased adherence to safe hand-
hygiene practices can have considerable effects. Applying the
findings of Pittet et al. (2000) and Rosenthal, Guzman, and
Safdar (2005), we estimated the number of infections pre-
vented in the patient-consequences condition in each study to
Table 3. Results of Analyses of Adherence to Safe Hand-Hygiene Practices in Experiment 2
Hand-hygiene adherence
Type of practitioner
and condition Pretest Posttest χ2(1) p d prep
Nurses
Personal consequences 81.43% (57/70) 83.87% (26/31) 0.09 .77 — —
Patient consequences 79.53% (101/127) 88.39% (99/112) 3.43 .06 0.33 .86
Physicians
Personal consequences 72.73% (16/22) 87.50% (14/16) 1.22 .27 — —
Patient consequences 72.41% (21/29) 92.86% (26/28) 4.12 .04 0.76 .89
Ancillary staff
Personal consequences 85.19% (23/27) 68.18% (15/22) −2.01 .16 — —
Patient consequences 89.13% (41/46) 88.89% (32/36) −0.00 .97 — —
1498 Grant, Hofmann
be between two and nine; these infections would have cost the
hospital between $9,000 and $30,000 per study (see Chen,
Chou, & Chou, 2005). This prevention of infections is a sub-
stantial return on investment, given the minimal costs of print-
ing and posting signs. If the increased hand-hygiene adherence
were sustained for a year across the hospital, the potential ben-
efits could include the prevention of more than 100 infections
and a savings of more than $300,000.
Future research should test perceived vulnerability and other
mediating mechanisms. For example, the patient-consequences
sign highlighted the implications for a group, whereas the
personal-consequences sign highlighted the implications for
an individual. Did the responsiveness to messages about
patient consequences reflect utilitarian reasoning, whereby
health care professionals aimed to promote the greatest good
for the greatest number of people? Given that individuals are
more likely to help a single person than to help multiple peo-
ple (Kogut & Ritov, 2007; Slovic, 2007), the opposite seems
likely. Signs might catalyze greater empathy by mentioning “a
patient” or “the patient in this room” instead of “patients”
(Goldstein, Cialdini, & Griskevicius, 2008). However, the
effects of this change in wording might be mitigated by health
care professionals’ perception of patients as part of a unitary,
cohesive group (Burson, Smith, & Faro, 2010). To investigate
these issues, future studies should systematically vary group
size. Nevertheless, if group size is a contributing factor, it may
be an explanatory mechanism rather than a confound: Hand-
hygiene behaviors can protect only one self, but many other
people. This fact accentuates the value of examining whether
patients are perceived as being part of a uniquely vulnerable
and valued population. Would similar effects emerge if signs
highlighted other groups affected by hand hygiene, such as
nurses, physicians, or health care professionals in general?
We also recommend combining quantity-based measures
of the use of hand-hygiene products and frequency-based
observational measures with quality-based measures, such as
microbiological tests and assessments of infection rates.
Finally, future research should investigate the implications of
our findings for other health, safety, and prosocial behaviors in
different populations. Are people more likely to improve their
exercise and eating habits, to quit smoking, to purchase life
insurance, to wear seat belts and helmets, to protect the envi-
ronment, or to take prescription medication when they are
reminded of the consequences of these behaviors for their
families rather than for themselves?
In conclusion, our findings suggest that health and safety
messages should focus not on the self, but rather on the target
group that is perceived as most vulnerable. As Levitt and
Dubner (2009) suggested, “When a doctor fails to wash his
own hands, his own life isn’t the one that is primarily endangered.
[The life endangered is that of] the next patient he treats”
(p. 207). Merely emphasizing the consequences for patients
motivates health care professionals to take more everyday health-
protective action. From the perspective of a health care profes-
sional, safety behavior is not necessarily “all about me.”
Acknowledgments
The authors thank Jessica Dixon, Janine Jones, Meera Kelley,
and Betty Woodard for assistance with data collection and Associate
Editor Julie Fitness, Noah Eisenkraft, Francesca Gino, and two
anonymous reviewers for feedback.
Declaration of Conflicting Interests
The authors declared that they had no conflicts of interest with
respect to their authorship or the publication of this article.
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