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When Do Financial Incentives Reduce Intrinsic Motivation?
Comparing Behaviors Studied in Psychological and Economic Literatures
Marianne Promberger and Theresa M. Marteau
King’s College London
Objective: To review existing evidence on the potential of incentives to undermine or “crowd out” intrinsic
motivation, in order to establish whether and when it predicts financial incentives to crowd out motivation for
health-related behaviors. Method: We conducted a conceptual analysis to compare definitions and operation-
alizations of the effect, and reviewed existing evidence to identify potential moderators of the effect. Results:
In the psychological literature, we find strong evidence for an undermining effect of tangible rewards on
intrinsic motivation for simple tasks when motivation manifest in behavior is initially high. In the economic
literature, evidence for undermining effects exists for a broader variety of behaviors, in settings that involve
a conflict of interest between parties. By contrast, for health related behaviors, baseline levels of incentivized
behaviors are usually low, and only a subset involve an interpersonal conflict of interest. Correspondingly, we
find no evidence for crowding out of incentivized health behaviors. Conclusion: The existing evidence does
not warrant a priori predictions that an undermining effect would be found for health-related behaviors.
Health-related behaviors and incentives schemes differ greatly in moderating characteristics, which should be
the focus of future research.
Keywords: incentives, health behavior, motivation, motivation crowding out, review
Policymakers are increasingly interested in the potential of
financial incentives to change individual behavior to achieve
health-related outcomes, including smoking cessation, weight loss,
attendance for disease screening, undergoing vaccination, or do-
nating blood. Such incentive schemes aimed at individuals or
patients are frequently met with criticism by the general public and
professional groups (e.g., Parke, Ashcroft, Brown, Marteau, &
Seale, 2011; Promberger, Brown, Ashcroft, & Marteau, 2011).
One concern about using financial incentives to change health-
related behaviors is that they may undermine, or “crowd out,”
intrinsic motivation for the behavior. For example, paying some-
one to lose weight might make that person less motivated to lose
weight once the incentive is removed. This concern is usually
raised with reference to one or more of three distinct, but related,
literatures: Titmuss’s (1970) The Gift Relationship, claiming det-
rimental effects of paying for blood donation, psychological liter-
ature starting with Deci (1971) on the undermining effect of
rewards on intrinsic motivation, and economic literature about
motivation crowding out or “motivation crowding theory” (Frey,
1997; Frey & Jegen, 2001). Although there is little empirical
evidence for Titmuss’s claim, the psychological and economic
literatures comprise a large body of laboratory and field studies
attempting to demonstrate unintended consequences of incentives.
It is sometimes assumed that the evidence base from these litera-
tures applies directly to the use of incentives to change health related
behaviors, implying that external rewards likely undermine motiva-
tion for these behaviors. For example, Johnston and Sniehotta (2010)
state, with reference to Deci, Koestner, and Ryan (1999) “[t]here is
good evidence from Self-Determination Theory that invoking ‘intrin-
sic motivation’ (i.e., based on the patient’s own values) results in more
sustainable behavior change after the intervention ends, than those
which only arouse ‘external motivation’” (p. 131).
The aim of the present article is twofold. First, we aim to
provide an overview of the literature on incentives for health-
related behaviors to establish whether an undermining effect of
rewards has been found to occur for these behaviors.
Second, we aim to compare the findings from this overview with
the existing evidence from the psychological literature on rewards
undermining intrinsic motivation and the economic literature around
motivation crowding out. We compare the evidence from these fields
to characterize the behaviors and contexts in which an undermining
effect has been observed, and where it has not (see Table 1).
What Are Health-Related Behaviors?
What do we mean by health-related behaviors? For this
article, we are interested in behaviors for which evidence exists
that they impact on health-related outcomes, and which for this
Marianne Promberger and Theresa M. Marteau, Centre for the Study of
Incentives in Health and Department of Psychology, King’s College Lon-
don, London, United Kingdom.
This article has been published under the terms of the Creative Com-
mons Attribution License (http://creativecommons.org/licenses/by/3.0/),
which permits unrestricted use, distribution, and reproduction in any me-
dium, provided the original author and source are credited. Copyright for
this article is retained by the author(s). Author(s) grant(s) the American
Psychological Association the exclusive right to publish the article and
identify itself as the original publisher.
This research was funded by the Centre for the Study of Incentives in
Health, from a strategic award from the Wellcome Trust Biomedical Ethics
Programme (PI Marteau: 086031/Z/08/Z).
Correspondence concerning this article should be addressed to Marianne
Promberger, Health Psychology, 5th Floor Bermondsey Wing, Guy’s Cam-
pus, King’s College London, London SE1 9RT, United Kingdom. E-mail:
marianne.promberger@kcl.ac.uk
THIS ARTICLE HAS BEEN CORRECTED. SEE LAST PAGE
Health Psychology © 2013 The Author(s)
2013, Vol. 32, No. 9, 950–957 0278-6133/13/$12.00 http://dx.doi.org/10.1037/a0032727
950
reason are the focus of public policy intervention to change
individuals’ behavior. These include smoking cessation, weight
loss, physical activity, medication adherence, vaccination,
screening for treatable or preventable disease, and blood and
organ donation. These behaviors obviously differ on a range of
characteristics, including how they affect health outcomes, who
benefits from the behavior (the individual or others), whether
health benefits are realized sooner or later, whether the behavior
needs to be sustained to accrue benefits, and in how any
financial incentive system would plausibly be implemented, for
example, whether it would be tied to the behavior such as
attending for screening, or a specified outcome, such as weight
loss.
Before we focus on the evidence regarding these behaviors, we
give an overview over the existing psychological and economic
literatures on the potentially undermining effect of rewards; see
Table 1 for an overview.
Psychological Literature on Rewards Undermining
Intrinsic Motivation
By 1970 the reinforcing effect of rewards on behavior was
firmly established in the learning theory literature. Deci (1971)
and Lepper, Greene, and Nisbett (1973) investigated a possible
exception to this effect: whether rewards could have a detri-
mental effect if they were offered for an activity that the
Table 1
Overview of Methods and Evidence From Cognitive Evaluation Theory and Motivation Crowding Theory, and Comparison With
Health-Related Behaviors
Intrinsic motivation
definition
Operationalization and
study design Evidence base Main findings
Health-related behaviors
compared
Psychological literature:
Cognitive evaluation
theory
Doing the task exclusively
for its own sake.
• Task and
participants selected
for high pre-reward
engagement with
task.
• Between-subject
design: one group
receives reward,
control group not.
• Task persistence is
compared between
groups after the
incentive is
removed.
• Large
evidence
base.
• Mostly lab
experiments
with
children.
• Simple
tasks for
which high
task
persistence
plausibly
reflects
high
intrinsic
motivation.
• Tangible, expected rewards
reduce behavior for
interesting tasks (where
behavior is initially high).
• No reduced persistence in
task for previously dull
tasks (where little time is
initially spent on task).
• More complex
motivation. Pure
intrinsic motivation
unlikely.
• Healthy behavior
levels initially low
(comparable with
“boring” tasks).
• Most behaviors
subject to self-control
problems.
Economic literature:
Motivation crowding
theory
Any of diverse
motivations going in the
opposite direction of
narrow self-interest.
Examples: altruism,
“civic-mindedness”
• Behaviors are
selected that are not
maximally self-
interested and
benefit other
parties. (e.g.,
volunteering, work
effort).
• Growing
evidence
base.
• Diverse
studies (lab
and field)
and more
diverse
behaviors
than CET
literature.
• Incentives can have an
unexpected effect in the
“wrong” direction.
• This is attributed to
crowding out of “intrinsic
motivation,” not
specifically defined.
• Circumstances under which
incentives have this effect,
opposite to the relative
price effect are not well
understood.
• While offering any
incentive can have a bad
effect vs. no incentive,
offering more money then
usually operates in the
expected direction.
• A conflict of interest
is not usually
prominent.
• Most behaviors
subject to self-control
problems.
• Positive or negative
incentive aims in
the direction
benefitting others.
(e.g., rewarding
volunteering;
penalties for
picking children up
late).
• Mostly between-
subject, but also
within-subject
designs.
• Motivation crowding
out is said to occur
when the incentive
has an effect opposite
of relative price
effect, while the
incentive is in place
or afterwards.
951
HEALTH INCENTIVES AND INTRINSIC MOTIVATION
individual enjoyed. The hypothesis was that rewards might
undermine “intrinsic motivation,” tested by comparing behavior
levels between a group that received a tangible reward and a
group that received no such reward, after the reward had been
removed. Both studies found that behavior levels were lower in
the group that had previously been rewarded. “Intrinsic moti-
vation” was defined as performance of a task with “no apparent
rewards except the activity itself” (Deci, 1971, p. 105) and
operationalized by choosing tasks that study participants al-
ready performed with sufficiently high persistence (puzzle-
solving and writing student newspaper headlines), and by se-
lecting as participants about 50% of nursery schoolchildren who
showed the highest initial spontaneous interest in a new draw-
ing opportunity (Lepper et al., 1973).
A wide body of research examined the prevalence of the under-
mining effect of rewards, with meta-analyses including 124 studies
(Cameron & Pierce, 1994) and 128 studies (Deci et al., 1999).
Virtually all these studies examine the effect of rewards on sub-
jects’ persistence in simple tasks such as puzzles or drawing
pictures, with participants being children (mostly preschool or
elementary school) in about half the studies, college students in the
others (Deci et al., 1999, Tables 1– 6).
These meta-analyses come to different conclusions, either
that the undermining effect of tangible external rewards on
intrinsic motivation is pervasive (Deci et al., 1999; Deci, Koes-
tner, & Ryan, 2001), or that it is limited (Cameron, 2001;
Cameron, Banko, & Pierce, 2001; Cameron & Pierce, 1994).
This difference seems to largely depend on methodological
decisions, in particular which studies to include in the meta-
analyses, and which study characteristics are considered to be
moderators. Of particular relevance to the question of crowding
out in health contexts is that the rewards have no undermining
or even a positive effect on “dull,” “boring,” “uninteresting”
tasks, that is, tasks for which initial intrinsic motivation is low,
operationalized by low initial task activity. In countering Cam-
eron’s (2001) argument for their inclusion, Deci, Ryan, and
Koestner (2001) specifically point out that the research field of
external rewards on intrinsic motivation “has always been de-
fined in terms of reward effects on intrinsic motivation for
interesting activities,” an argument supported by authors not
directly involved in the debate (Lepper, Henderlong, & Gin-
gras, 1999). Following the original definition and operational-
ization of intrinsic motivation, high levels of pre-reward behav-
ior are assumed to imply high intrinsic motivation.
Cognitive evaluation theory (CET; Deci & Ryan, 1985) predicts
that rewards only reduce intrinsic motivation when they are per-
ceived as controlling the behavior, and might actually enhance
intrinsic motivation if they engender feelings of competence. In
line with this prediction, no reduction of intrinsic motivation is
found if the reward is not tangible, for example, if it comprises
verbal praise, and if it is unexpected (Cameron & Pierce, 1994;
Deci et al., 1999).
Economic Literature on “Motivation Crowding Out”
The term “motivation crowding out” was coined in the eco-
nomic literature to refer to an undermining effect of rewards and
its definition extended to any effect that is opposite to the relative
price effect of standard economic theory, whereby reduced costs
should increase behavior, and increased costs should reduce it. The
effect, therefore, includes cases where penalties increase behavior,
and focuses on behavior concurrent with the incentive rather than
after its removal.
Economic studies on motivation crowding out include new and
often more complex behaviors than the puzzles and tasks used in
the cognitive evaluation theory literature. Laboratory studies often
use economic games that require some cooperation between par-
ties or a trade-off between interests of different parties, for exam-
ple in principal-agent problems involving an agent acting with
consequences for the principal, who relies on the agent, such as an
employer relying on employee work effort. Questionnaire mea-
sures of real-world voting decisions have also been used: In a
within-subject design, Frey and Oberholzer-Ghee (1997) found
acceptance of the siting of a nuclear waste repository close by
dropped from about 50% to about 25% when financial compen-
sation was offered. Field experiments showed, for example, par-
ents to be more often late in picking up their children from daycare
when a fine was imposed than before (and even after the fine was
removed; Gneezy & Rustichini, 2000), and volunteers who were
paid a small amount worked fewer hours than unpaid volunteers
(Frey & Goette, 1999).
Frey and Jegen’s (2001) motivation crowding theory builds on
cognitive evaluation theory and also includes the perception of the
incentive as controlling or undermining autonomy as a mechanism
that leads to motivation crowing out. It also explicitly allows for
the possibility of extrinsic incentives to “crowd in,” or increase,
intrinsic motivation, for example through the development of new
preferences favoring the incentivized behavior.
Economic research currently lags behind the psychological
literature as measured by the sheer volume of studies. Meta-
analyses are not available. The most comprehensive unsystem-
atic review to date (Frey & Jegen, 2001), including empirical
studies as well as anecdotal evidence, concludes that rewards
may sometimes crowd out and sometimes crowd in—that is,
increase—intrinsic motivation. Economic research about
crowding out is conducted given the strong theoretical and
empirically well-founded backdrop of the relative price effect:
Ample evidence exists that behavior is usually in line with
incentives (e.g., Prendergast, 1999), and research on motivation
crowding out is looking for the exceptions. Although increasing
numbers of studies uncover such exceptions, the conditions
under which they occur are currently not well understood
(Gneezy, Meier, & Rey-Biel, 2011).
Results
Evidence From Studies About Health-Related
Behaviors
Definition and operationalization of an undermining effect
of rewards on motivation. In interpreting the evidence for an
undermining effect of rewards on health-related behaviors, we will
rely both on the definition and operationalization used in the
psychological cognitive evaluation theory and in the economic
motivation crowding out literature. Both literatures focus on a
difference in levels of behavior between the incentivized group
and a non-incentivized control group when operationalizing an
undermining effect of rewards and a motivation crowding out
952 PROMBERGER AND MARTEAU
effect, respectively. The CET literature focuses on the difference
after removal of the reward: After an initial period of pre-reward
task activity (sometimes omitted), the experimental group is re-
warded for the task; subsequently rewards are removed, and time
spent on the task is compared between the experimental and a
control group in a “free-choice” period. Less time spent on the task
in the previously rewarded group during this period than in the
control group indicates that the reward has reduced intrinsic mo-
tivation.
The definition of “motivation crowding out” in economic re-
search includes any effect that is opposite to the relative price
effect of standard economic theory: rewards decreasing behavior
levels, and penalties increasing behavior levels. Correspondingly,
the economic literature includes operationalizations of a crowding
out effect as the difference in behavior between an incentivized
and a control group while the incentive is in place (Frey, 1997;
Frey & Jegen, 2001).
The focus in both literatures on differences in behavior as the
relevant outcome means we can look for evidence of an under-
mining effect of rewards even in health-related behavior studies
which do not set out to look for this effect: In randomized con-
trolled trials of health behavior incentives, evidence for the effec-
tiveness of the incentive provides evidence for the absence of
motivation crowding out as defined and operationalized by econ-
omists. If the incentivized and the control groups are compared
during follow-up—that is, after the removal of incentives,— evi-
dence for motivation crowding out would require lower levels of
the previously incentivized behavior in the previously incentivized
group than in the control group.
Studies explicitly addressing an undermining effect of
rewards. Few studies have examined the impact of rewarding
health behavior change with a specific focus on their potential to
undermine intrinsic motivation.
In a field experiment, Charness and Gneezy (2009) incentivized
college students for gym attendance and found students who had
received contingent incentives attended the gym more frequently
than the control group after incentives were removed. This result
is opposite to the effect that would be predicted by motivation
crowding theory. While acknowledging the limits of gym atten-
dance as an outcome measure, the result in fact supports motiva-
tion “crowding in,” attributed by the authors to habit formation.
In a randomized controlled trial with children, Cooke et al.
(2011) measured the effect of exposure and rewards (tangible
stickers and intangible praise) on intake and liking of a vegetable
up to 3 months after the intervention. Liking of the food can be
seen as similar to Deci’s (1971) definition of intrinsic motivation.
Children who had received tangible rewards consumed more of the
vegetable than all other groups; they liked the vegetable equally
well as other exposure groups, and more than the control group.
This evidence does not support an undermining effect of the
tangible incentive. Although motivation is a very unreliable pre-
dictor of behavior (Webb & Sheeran, 2006), tastes and preferences
formed at this early age are likely to have repercussions throughout
life.
Ledgerwood and Petry (2006) assessed the impact of incentives
on motivation in the context of substance use. Motivation was
assessed using questions based on the stages of change model. The
group receiving incentives did not differ in motivation from the
group receiving no incentives up to 3 months after the incentives
had stopped, hence there was no evidence in this study either that
the incentives reduced motivation.
Studies indirectly assessing a crowding out effect: Random-
ized controlled trials (RCTs) of financial incentive
effectiveness. Cahill and Perera (2011) reviewed evidence from
19 studies (RCTs and controlled trials) assessing the impact of
financial incentives on smoking cessation (not including pregnant
women) and concluded that financial incentives resulted in higher
quit rates while the incentive was in place. This is evidence in the
opposite direction from that which would be predicted by motiva-
tion crowding theory. There was no difference between the incen-
tivized and control group at follow-up, after the incentive was no
longer in place, providing no evidence for an undermining effect of
the incentive as operationalized in study designs building on
cognitive evaluation theory. The largest study in the review (Volpp
et al., 2009) stands out for finding higher quit rates in the previ-
ously incentivized group at 15-month follow-up, thus providing
direct evidence against an undermining effect of the incentive.
A meta-analysis of nine trials on incentives for weight loss
(Paul-Ebhohimhen & Avenell, 2008) found no difference between
previously incentivized and control groups at follow-up, thus pro-
viding no evidence for reduced, or increased, motivation. In an
RCT not included in this review (Volpp et al., 2008), the incen-
tivized groups lost more weight than the control group during
incentivization, and at 7-month follow-up participants in the pre-
viously incentivized groups, unlike those in the control group,
weighed less than at baseline.
In a systematic review, Niza, Tung, and Marteau (2013, this
issue) found no evidence that incentives for blood donations crowd
out motivation while the incentive is in place; too few studies
included a post-incentive follow-up to assess post-incentive im-
pact. Randomized controlled trials about the effectiveness of in-
centives on adherence to medical treatment show that such incen-
tives are sometimes effective, providing evidence against
crowding out while the incentive is in place (e.g., Barnett, So-
rensen, Wong, Haug, & Hall, 2009; Malotte, Hollingshead, &
Larro, 2001; Tulsky et al., 2000). Long, Jahnle, Richardson, Loe-
wenstein, and Volpp (2012) found no evidence for incentive ef-
fectiveness for blood glucose control in a 6-month RCT among
African American veterans with diabetes, but outcomes in the
incentive group were no worse than the control group (outcomes in
the peer mentoring group, however, were better than in the control
group). Barnett, Sorensen, Wong, Haug, and Hall (2009) also
included a follow-up 4 weeks after removal of the incentive and
found no difference between the previously incentivized and the
control group, providing no evidence for a persisting undermining
effect of the incentive.
Randomized controlled trials of incentives to attend screening
for sexually transmitted diseases have found either no effect of the
incentive (Low et al., 2007) or a positive effect (Malotte et al.,
2004), hence generating no evidence to support the hypothesis that
rewards reduce motivation. Kohler and Thornton (2012), however,
report that in an incentive program in Malawi the randomly as-
signed incentive had no effect on HIV infections, but after it was
paid out, risky sexual behavior increased by nine percentage points
for men and decreased by seven percentage points for women. One
possible mechanism suggested by the authors is that money may
have enabled the men to purchase risky sex and enabled the
women to avoid selling it, which would imply the incentive to have
953
HEALTH INCENTIVES AND INTRINSIC MOTIVATION
changed, for both men and women, the means to follow through on
pre-existing motivation. In an RCT of incentives contingent on
testing for sexually transmitted diseases in Tanzania, there was a
positive effect of the incentive on self-reported behavior change
(Packel, Dow, de Walque, Isdahl, & Majura, 2012), and a positive
effect of incentives on self-reported motivation (de Walque, Dow,
Medlin, & Nathan, 2012). Although these endpoints are not reli-
able indicators of behavior change, they provide evidence against
crowding out.
Comparison of Health-Related Behaviors With
Behaviors for Which an Undermining Effect has Been
Demonstrated
There seems to be very little evidence of an undermining effect
of rewards on health-related behaviors. We now compare health
behaviors and those studied in the psychological and economic
literatures reviewed above for which an undermining effect is
frequently found, in order to identify possible differences that
might explain the different findings.
Table 2 summarizes our comparison of key characteristics of the
behaviors used in these former two literatures with the character-
istics of the different health-related behaviors for which incentive
schemes have been used. The last column shows whether evidence
in each domain supports the existence of an undermining effect.
Although the evidence bases vary in size and the extent to which
they have focused on revealing reduced behavior in the face of
rewards, the pattern of findings support the interpretation of the
key characteristics as moderators: undermining effects of incen-
tives depend on a high baseline level for simple tasks, and on an
interpersonal conflict of interest in more complex behaviors, nei-
ther of which are dominant for health-related behaviors that are
targets for incentive schemes. For health-related behaviors that
rely on self-control, incentives may enhance feelings of compe-
tence and might actually increase motivation and behavior even
post-incentive, though little evidence for this long-term effect
exists.
Rewards would be offered to individuals with low rather
than high initial behavior levels. The most important difference
between health behaviors and those studied in the cognitive eval-
uation theory literature concerns levels of the pre-reward behaviors
and intrinsic motivation, an established moderator of the under-
mining effect of rewards (Deci et al., 1999). Rewards for health
related behaviors aim to increase low baseline levels of a particular
behavior that enhances health. For example, rewards would be
offered to smokers if they quit, to overweight people if they lose
weight (by consuming fewer or expending more calories), to those
who rarely engage in physical activity if they increase their levels
of physical activity. As noted above, meta-analyses find that for
“dull” and “boring” tasks for which subjects show low pre-reward
persistence, a reward has either no undermining effect or even a
small beneficial effect (Deci et al., 1999). We note that the intrinsic
motivation component of enjoyment may still be high for some
health-related behaviors such as physical activity that are never-
theless rarely engaged in due to a number of internal or external
barriers—the experience of enjoying running on the rare occasions
that one does it. This is a result of the more complex set of
motivations for health-related behaviors, for which high or low
behavior levels do not directly map onto high or low intrinsic
motivation, as is the case for the simple tasks without external
benefits that are used in cognitive evaluation theory studies. How-
ever, in cognitive evaluation theory itself, operationalization of
crowding out using behavioral measures takes precedence over
measures of task enjoyment. The complex nature of motivation
also means that health-related behaviors are practically never en-
gaged in only for their own sake, but are at least partly motivated
by considerations about outcomes such as improved fitness or
attractiveness, so none of them meet the CET definition of high
intrinsic motivation under any circumstances of which we can
think.
Many health-related behaviors involve problems of
self-control. Many health-related behaviors typically involve a
conflict of considerations for long-term outcomes such as im-
proved fitness with preferences for outcomes close in time, such as
staying on the couch to watch television. An individual must trade
these conflicting preferences off against each other when deciding
what to do. It is well established that these trade-offs are tempo-
rally inconsistent (Frederick, Loewenstein, & O’Donoghue, 2002):
When the sooner benefit is immediately available, it is preferred
more than the individual would have predicted. Plans not to eat
dessert are overthrown when it is on the table. The change in
Table 2
Comparison of Key Characteristics of Behaviors in Studies of: Cognitive Evaluation Theory Studies, Motivation Crowding Theory
Studies, and Incentives Schemes Targeting Health-Related Behaviors
Literature Specific behavior
High initial pre-reward
behavior levels?
Conflict of interest
between parties?
Self-control
problem?
Evidence for
crowding out?
Cognitive evaluation theory Yes No No Yes
Motivation crowding theory No Yes No Yes
Health-related behaviors
Smoking cessation No Yes Yes No
Reduced calorie consumption No No Yes No
Increased physical activity No No Yes No
Vaccination and screening:
• noncommunicable disease No No No No
• communicable disease No Yes No No
Blood donation No Yes No No
Note. Boldface is a rough indicator for strength of the evidence (last column) and strength of arguments for the yes/no characterization (other columns).
954 PROMBERGER AND MARTEAU
predicted behavior as the temptation becomes imminent is known
as a problem of impulse control, or self-control (Ainslie, 1975;
Baumeister, Heatherton, & Tice, 1994). As far as we are aware, no
studies in the context of cognitive evaluation theory involve be-
haviors that challenge impulse control in this way. For health
behaviors that rely on self-control, effective rewards might plau-
sibly enhance perceived competence, making an undermining ef-
fect of the reward less likely, and a positive effect on behavior
more likely. This effect is, for example, found in cognitive eval-
uation theory studies that involve verbal praise for difficult tasks
(Deci et al., 1999). An effective incentive may work by adding to
the delayed benefits of healthy behavior in a way that is just large
enough, and just certain enough, and just close enough in time, to
tilt behavior away from the option conferring immediate benefit,
thereby effectively training self control mechanisms.
An interpersonal conflict of interest is less prominent for
health-related behaviors. Evidence from economic studies
about motivation crowding out relies mostly on behaviors and
tasks for which narrow self-interest must be traded off against
benefits to others. Before the reward is introduced, behavior is not
maximally self-interested, demonstrating “intrinsic” motivation to
contribute to others’ well-being. For example, employees work
even when not supervised, and parents are not always late in
picking up their children. When crowding out occurs, the behavior
becomes more narrowly self-interested, that is, this intrinsic mo-
tivation is undermined; for example, parents are more often late.
All three of the potential mechanisms suggested by Bowles (2008)
for an undermining effect of incentives in addition to cognitive
evaluation theory rely on this conflict of interest: framing of the
decision as one where self-interest is the appropriate guiding
principle; the incentive system shaping long-term narrowly self-
interested preferences; the incentive conveying information, for
example about lack of trust in employee work effort. Also based on
a conflict of interest is the explanation offered by Heyman and
Ariely (2004) whereby a situation requiring altruistic behavior that
was previously situated in the “social market,” where no payment
is expected, shifts to the “money market,” where narrow self-
interest dictates behavior and payment for altruistic behavior is or
is not high enough.
This structure of conflicting interests resembles the plausible
motivation structure for some, but certainly not for all, health
behaviors. It most closely resembles the case for blood and organ
donation, where narrow self-interest is not at all served by the
behavior. Behaviors such as disease screening or vaccinations for
communicable diseases benefit both the individual and others
(through herd immunity). These behaviors are most likely primar-
ily motivated by interest in the health benefits to oneself, but may
additionally be motivated by considerations for benefits to others.
Rewards for donation, screening, and vaccination decisions might
therefore be seen by those targeted as direct attempts by others
(society, the health service, the organ recipient) to buy these
benefits from them—a shift to the money market. Crowding out
might occur. However, Frey and Jegen (2001) note that where
crowding out occurs, the offer of an incentive reduces behavior
compared with the situation in which no incentive is offered, but
once an incentive is offered, increasing payment increases behav-
ior. From a policy perspective, the motivating effect of a large
enough incentive might be worth it, depending on how much
beneficial behavior is gained.
For most behaviors that confer a health benefit when sustained
in the long term, such as smoking cessation, weight loss, and
physical activity, a conflict of interest between different parties is
much less prominent. Harms to others from some unhealthy be-
haviors certainly exist. The most prominent example concerns the
hazards of second-hand smoke, which has been used to motivate
behavior change and legislation restricting where smoking can
occur. In such cases, the offer of an incentive may be perceived by
those targeted as a payment, for example from the state, to further
the interest of others worthy of protection, or its own interests of
reducing health care costs. However, for most of these behaviors,
the prominent conflict of interest is less between different persons
and more between different outcomes within the person him- or
herself. Given that a large proportion of smokers and those who are
overweight or inactive already have stated intentions to change
these behaviors, the reward seems more likely to be seen as a
welcome additional benefit for a behavior for which motivation
already exists (Mantzari, Vogt, & Marteau, 2012). Although the
intrapersonal, intertemporal conflict of interest can be conceptual-
ized as one between present and future selves (Parfit, 1984), the
reward would come from outside the person, a different situation
from that of one party offering the reward in an interpersonal
conflict of interest.
Discussion
Evidence for the undermining effects of rewards in the psycho-
logical and economic literatures needs to be applied cautiously to
health-related behaviors. The psychological literature on cognitive
evaluation theory consistently reports an undermining effect of
rewards only for behaviors for which initial intrinsic motivation,
and initial behavior levels, are high. Such high pre-reward intrinsic
motivation and behavior levels are not found in health-related
behaviors that are the focus of incentive schemes. Studies in the
economic literature that have found a crowding out effect usually
involve a conflict of interest between different parties, with most
mechanisms explaining this effect relying on this interpersonal
conflict. Among the health-related behaviors, such a conflict of
interest is evident for blood donation, for communicable disease
screening, and possibly for smoking cessation, but it is less prom-
inent for behaviors such as achieving weight loss or physical
activity. Even where it is prominent, with one exception, we do not
find evidence for rewards reducing motivation in randomized
controlled trials on incentive effectiveness.
Whether rewards undermine the initial “intrinsic” (not narrowly
self-interested) motivation for the targeted behavior may depend
on whether the reward is seen as an attempt to “purchase” the
behavior from the individual in a “money market.” Yet even where
this is likely to be the case, such as for blood donation, evidence
for lower levels of donation at a population level is not found
(Niza, Tung, & Marteau, 2013, this issue). Because it is theoreti-
cally plausible that employer incentives for employee health be-
havior change (Volpp, Asch, Galvin, & Loewenstein, 2011) are
perceived in this way more than incentives paid by researchers,
employers may want to further minimize the risk of crowding out
by framing the message of incentives as aiding individuals rather
than as a bribe for better work performance. We note, however,
that the trial showing the greatest long-term positive effect of
incentives for smoking cessation (Volpp et al., 2009) was con-
955
HEALTH INCENTIVES AND INTRINSIC MOTIVATION
ducted in an employment setting and provides evidence against a
crowding out effect. In all these cases, crowding out for some
individuals may be outweighed by other individuals being suffi-
ciently extrinsically motivated by the reward to perform the be-
havior when previously they did not. The question whether the
reward should be offered could in this case be seen as a simple
cost-effectiveness decision, informed by the impact of the incen-
tive on the target behavior.
When rewards help tilt the balance of benefits in favor of the
delayed, healthier outcome, they may shape behavior to bring it
more in line with an underlying motivation that has previously
been present albeit not manifest in behavior. If such a reward is
perceived as confirming the individual’s autonomy rather than
controlling his or her behavior, cognitive evaluation theory would
predict it would enhance intrinsic motivation. Frey and Jegen
(2001) likewise give a theoretical account for such “crowding in”
to occur. Confirming this, the evidence on the effectiveness of
financial incentive schemes targeting behaviors that involve prob-
lems of self-control does not reveal crowding out. Importantly,
uncertainty remains about the design of financial incentive
schemes, including the targeted behavior, that are most likely to
lead to sustained behavior change, and for whom. Reviews and
primary studies that address this question could usefully collect
more evidence to substantiate or refute the analysis in this article
regarding the limited number of contexts in which motivation
crowding out is likely to occur when financial incentives are
offered for health-related behavior change.
References
Ainslie, G. (1975). Specious reward: A behavioral theory of impulsiveness
and impulse control. Psychological Bulletin, 82, 463– 496. doi:10.1037/
h0076860
Barnett, P. G., Sorensen, J. L., Wong, W., Haug, N. A., & Hall, S. M.
(2009). Effect of incentives for medication adherence on health care use
and costs in methadone patients with HIV. Drug and Alcohol Depen-
dence, 100, 115–121. doi:10.1016/j.drugalcdep.2008.09.017
Baumeister, R. F., Heatherton, T. F., & Tice, D. M. (1994). Losing control:
How and why people fail at self-regulation. San Diego, CA: Academic
Press.
Bowles, S. (2008). Policies designed for self-interested citizens may un-
dermine “the moral sentiments”: Evidence from economic experiments.
Science, 320, 1605–1609. doi:10.1126/science.1152110
Cahill, K., & Perera, R. (2011). Competitions and incentives for smoking
cessation. Cochrane Database of Systematic Reviews. doi:10.1002/
14651858.CD004307.pub4
Cameron, J. (2001). Negative effects of reward on intrinsic motivation—A
limited phenomenon: Comment on Deci, Koestner, and Ryan (2001).
Review of Educational Research, 71, 29 – 42. doi:10.3102/
00346543071001029
Cameron, J., Banko, K. M., & Pierce, W. D. (2001). Pervasive negative
effects of rewards on intrinsic motivation: The myth continues. The
Behavior Analyst, 24(1), 1– 44.
Cameron, J., & Pierce, W. D. (1994). Reinforcement, reward, and intrinsic
motivation: A meta-analysis. Review of Educational Research, 64, 363–
423. doi:10.3102/00346543064003363
Charness, G., & Gneezy, U. (2009). Incentives to exercise. Econometrica,
77, 909 –931. doi:10.3982/ECTA7416
Cooke, L. J., Chambers, L. C., Añez, E. V., Croker, H. A., Boniface, D.,
Yeomans, M. R., & Wardle, J. (2011). Eating for pleasure or profit: The
effect of incentives on children’s enjoyment of vegetables. Psychologi-
cal Science, 22, 190 –196. doi:10.1177/0956797610394662
Deci, E. L. (1971). Effects of externally mediated rewards on intrinsic
motivation. Journal of Personality and Social Psychology, 18, 105–115.
doi:10.1037/h0030644
Deci, E. L., Koestner, R., & Ryan, R. M. (1999). A meta-analytic review
of experiments examining the effects of extrinsic rewards on intrinsic
motivation. Psychological Bulletin, 125, 627– 668. doi:10.1037/0033-
2909.125.6.627
Deci, E. L., Koestner, R., & Ryan, R. M. (2001). Extrinsic rewards and
intrinsic motivation in education: Reconsidered once again. Review of
Educational Research, 71(1), 1–27. doi:10.3102/00346543071001001
Deci, E. L., & Ryan, R. M. (1985). Intrinsic motivation and self-
determination in human behavior. New York, NY: Plenum Press.
Deci, E. L., Ryan, R. M., & Koestner, R. (2001). The pervasive negative
effects of rewards on intrinsic motivation: Response to Cameron (2001).
Review of Educational Research, 71, 43–51. doi:10.3102/
00346543071001043
de Walque, D., Dow, W. H., Medlin, C., & Nathan, R. (2012). Stimulating
demand for AIDS prevention: Lessons from the RESPECT trial. Na-
tional Bureau of Economic Research Working Paper Series, 17865.
Frederick, S., Loewenstein, G., & O’Donoghue, T. (2002). Time discount-
ing and time preference: A critical review. Journal of Economic Liter-
ature, 40, 351– 401. doi:10.1257/002205102320161311
Frey, B. S. (1997). On the relationship between intrinsic and extrinsic work
motivation. International Journal of Industrial Organization, 15, 427–
439. doi:10.1016/S0167-7187(96)01028-4
Frey, B. S., & Goette, L. (1999). Does pay motivate volunteers? Working
Paper Series, (Working Paper No. 7). Retrieved from http://e-collection.
library.ethz.ch/eserv/eth:25512/eth-25512– 01.pdf
Frey, B. S., & Jegen, R. (2001). Motivation crowding theory. Journal of
Economic Surveys, 15, 589 – 611. doi:10.1111/1467-6419.00150
Frey, B. S., & Oberholzer-Gee, F. (1997). The cost of price incentives: An
empirical analysis of motivation crowding-out. American Economic
Association, 87, 746 –755.
Gneezy, U., Meier, S., & Rey-Biel, P. (2011). When and why incentives
(don’t) work to modify behavior. The Journal of Economic Perspectives,
25, 191–210. doi:10.1257/jep.25.4.191
Gneezy, U., & Rustichini, A. (2000). A fine is a price. The Journal of Legal
Studies, 29, 1–17. doi:10.1086/468061
Heyman, J., & Ariely, D. (2004). Effort for payment: A tale of two
markets. Psychological Science, 15, 787–793. doi:10.1111/j.0956-7976
.2004.00757.x
Johnston, M., & Sniehotta, F. (2010). Financial incentives to change
patient behaviour. Journal of Health Services Research and Policy, 15,
131–132. doi:10.1258/jhsrp.2010.010048
Kohler, H-P., & Thornton, R. L. (2012). Conditional cash transfers and
HIV/AIDS prevention: Unconditionally promising? The World Bank
Economic Review, 26, 165–190. doi:10.1093/wber/lhr041
Ledgerwood, D. M., & Petry, N. M. (2006). Does contingency manage-
ment affect motivation to change substance use? Drug and Alcohol
Dependence, 83, 65–72. doi:10.1016/j.drugalcdep.2005.10.012
Lepper, M. R., Greene, D., & Nisbett, R. E. (1973). Undermining chil-
dren’s intrinsic interest with extrinsic reward: A test of the “overjusti-
fication” hypothesis. Journal of Personality and Social Psychology, 28,
129 –137. doi:10.1037/h0035519
Lepper, M. R., Henderlong, J., & Gingras, I. (1999). Understanding the
effects of extrinsic rewards on intrinsic motivation—Uses and abuses of
meta-analysis: Comment on Deci, Koestner, and Ryan (1999). Psycho-
logical Bulletin, 125, 669 – 676. doi:10.1037/0033-2909.125.6.669
Long, J. A., Jahnle, E. C., Richardson, D. M., Loewenstein, G., & Volpp,
K. G. (2012). Peer mentoring and financial incentives to improve glu-
cose control in African American veterans: A randomized trial. Annals
of Internal Medicine, 156, 416 – 424. doi:10.7326/0003-4819-156-6-
201203200-00004
956 PROMBERGER AND MARTEAU
Low, N., McCarthy, A., Macleod, J., Salisbury, C., Campbell, R., Roberts,
T.E.,...Group, C. S. S. P. (2007). Epidemiological, social, diagnostic
and economic evaluation of population screening for genital chlamydial
infection. Health Technology Assessment, 11, iii-iv, ix-xii, 1–165.
Malotte, C. K., Hollingshead, J. R., & Larro, M. (2001). Incentives vs.
outreach workers for latent tuberculosis treatment in drug users. Amer-
ican Journal of Preventive Medicine, 20, 103–107. doi:10.1016/S0749-
3797(00)00283-X
Malotte, C. K., Ledsky, R., Hogben, M., Larro, M., Middlestadt, S., St. Lawrence,
J.S.,...The GCAP Study Group. (2004). Comparison of methods to
increase repeat testing in persons treated for gonorrhea and/or chlamydia at
public sexually transmitted disease clinics. Sexually Transmitted Diseases,
31, 637– 642. doi:10.1097/01.olq.0000143083.38684.9d
Mantzari, E., Vogt, F., & Marteau, T. M. (2012). The effectiveness of
financial incentives for smoking cessation during pregnancy: Is it from
being paid or from the extra aid? BMC Pregnancy Childbirth, 12, 24.
doi:10.1186/1471-2393-12-24
Niza, C., Tung, B., & Marteau, T. M. (2013). Incentivizing blood donation:
Systematic review and meta-analysis to test Titmuss’s hypotheses.
Health Psychology.
Packel, L., Dow, W., de Walque, D., Isdahl, Z., & Majura, A. (2012).
Sexual behavior change intentions and actions in the context of a
randomized trial of a conditional cash transfer for HIV prevention in
Tanzania. World Bank Policy Research Working Paper, No. 5997.
Parfit, D. (1984). Reasons and persons. Oxford, UK: Oxford University
Press.
Parke, H., Ashcroft, R., Brown, R., Marteau, T. M., & Seale, C. (2011).
Financial incentives to encourage healthy behaviour: An analysis of UK
media coverage. Health Expectations. Advanced online publication.
doi:10.1111/j.1369-7625.2011.00719.x
Paul-Ebhohimhen, V., & Avenell, A. (2008). Systematic review of the use
of financial incentives in treatments for obesity and overweight. Obesity
Reviews, 9, 355–367. doi:10.1111/j.1467-789X.2007.00409.x
Prendergast, C. (1999). The provision of incentives in firms. Journal of
Economic Literature, 37, 7– 63. doi:10.1257/jel.37.1.7
Promberger, M., Brown, R. C. H., Ashcroft, R. E., & Marteau, T. M.
(2011). Acceptability of financial incentives to improve health outcomes
in U.K. and U.S. samples. Journal of Medical Ethics, 37, 682– 687.
doi:10.1136/jme.2010.039347
Titmuss, R. (1970). The gift relationship: From human blood to social
policy. London, UK: George Allen and Unwin.
Tulsky, J., Pilote, L., Hahn, J. A., Zolopa, A. J., Burke, M., Chesney, M.,
& Moss, A. R. (2000). Adherence to isoniazid prophylaxis in the
homeless: A randomized controlled trial. Archives of Internal Medicine,
160, 697–702. doi:10.1001/archinte.160.5.697
Volpp, K. G., Asch, D., Galvin, R., & Loewenstein, G. (2011). Redesign-
ing employee health incentives—Lessons from behavioral economics.
The New England Journal of Medicine, 365, 388 –390. doi:10.1056/
NEJMp1105966
Volpp, K. G., John, L., Troxel, A., Norton, L., Fassbender, J., & Loew-
enstein, G. (2008). Financial incentive-based approaches for weight loss:
A randomised trial. Journal of the American Medical Association, 300,
2631–2637. doi:10.1001/jama.2008.804
Volpp, K. G., Troxel, A., Pauly, M., Glick, H., Puig, A., Asch, D.,...
Audrain-Mcgovern, J. (2009). A randomized, controlled trial of financial
incentives for smoking cessation. The New England Journal of Medi-
cine, 360, 699 –709. doi:10.1056/NEJMsa0806819
Webb, T. L., & Sheeran, P. (2006). Does changing behavioral intentions
engender behavior change? A meta-analysis of the experimental evi-
dence. Psychological Bulletin, 132, 249 –268.
Received August 13, 2012
Revision received January 11, 2013
Accepted January 24, 2013 䡲
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HEALTH INCENTIVES AND INTRINSIC MOTIVATION
Correction to Promberger and Marteau (2013)
The article “When Do Financial Incentives Reduce Intrinsic Motivation? Comparing Behaviors
Studied in Psychological and Economic Literatures” by Marianne Promberger and Theresa M.
Marteau (Health Psychology, Vol. 32, No. 9, pp. 950 –957. doi: 10.1037/ a0032727), was published
with the incorrect copyright line. The copyright line should have read ©2013 The Author(s).
Additionally, the Author Note should have stated, “This article has been published under the terms
of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0/), which
permits unrestricted use, distribution, and reproduction in any medium, provided the original author
and source are credited. Copyright for this article is retained by the author(s). Author(s) grant(s) the
American Psychological Association the exclusive right to publish the article and identify itself as
the original publisher.” The online version of this article has been corrected.
http://dx.doi.org/10.1037/hea0000036
