This is Part 8 of the Nudge Database.
Part I|| Part II|| Part III|| Part IV|| Part V || Part VIPart VIIPart IX @Makeuya
looked at different ways to encourage employees (n=1299, 81% female, mean age
41) at a health care management and IT consulting company to complete Health
Risk Assessments (HRAs); specifically examining whether a lottery is more
effective than a direct payment of equivalent monetary value (i.e. a gift
certificate). There was a control group in addition to these two treatment
authors cite inspiration from the Dutch postal code lottery for their design,
which incorporates regret aversion. In their lottery, employees were divided
into teams of 4-8 and one team was randomly selected as the winner each week. Each
member of the winning team who had completed the HRA prior to the time of the
drawing would win $100. If at least 80% of the members of the team completed
the HRA, the prize would increase to $125.
showed significantly higher HRA completion for the lottery group (64%) than the
gift certificate group (44%) and the control (40%). Effects were larger for lower-income
Tags: financial incentives / lotteries
Source: Haisley et al. (2012), ‘The impact of alternative
incentive schemes on completion of health risk assessments’ American
Journal of Health Promotion
Nudge: This experiment (n=150) tested
the impact of various notes on the likelihood of a person completing a survey.
For those who received only the survey and cover page the completion rate was
36%, compared to 48% for those with a handwritten message on the front-page and
76% when the survey was accompanied by a hand-written post-it note.
Source: Garner (2005), ‘Post-It® note persuasion: a
Journal of Consumer Psychology
authors conducted a Safety
Attitudes Questionnaire (SAQ) in eight hospitals participating in a
trial of a
WHO surgical safety checklist. Clinicians (n=281) in the
had a mean SAQ score of 3.91 (1-5 scale where 5 represents better safety
attitude) while the post-intervention group (n=257) had a statistically
significantly different mean of 4.01. Improvements in postoperative
were associated with improved perception of teamwork and safety climate
respondents, suggesting that changes in these may be partially
the effect of the checklist. Clinicians held the checklist in high
93.4% would want it used if they were undergoing surgery themselves.
Tags: checklists / healthcare
Source: Haynes et al (2011). ‘Changes in safety
attitude and relationship to decreased postoperative morbidity and ', Quality Safety Health Care
Nudge: The authors elicit subjects'
beliefs about the likelihood that they will redeem a mail-in form. Expected
redemption rates exceed actual redemption rates by 49 percentage points,
meaning that subjects are overoptimistic about their likelihood of redemption.
The authors conduct three treatments to reduce overoptimism; (1) informing
subjects about a previous cohort's redemption rates, (2) reminding subjects
about the redemption deadline and (3) reducing transaction costs (i.e. making
the third nudge had any effect and it reduced overoptimism by one half. The
third nudge increased redemption but had no effect on beliefs suggesting that
weak cost-salience is the mechanism for overoptimism.
Source: Letzler & Tasoff (2013) ‘Everyone Believes in Redemption:
Nudges and Overoptimism in Costly Task Completion’, Working Paper.
compared the effectiveness of a conventional informational poster intervention
designed to increase condom use among gay men to a ‘self-justification’
intervention designed to bridge the hot-cold behavioral gap between acting in
the throes of passion and later cool objectivity. Subjects in the latter group
were sent a questionnaire which instructed them to recall as vividly as
possible an unsafe (in terms of protection) sexual encounter they had
previously engaged in and were asked to indicate which of a given list of
possible self-justifications for having unsafe sex had been in their mind at
the moment they decided not to use a condom. They were then how reasonable
those justifications seemed now and to briefly justify those new responses.
percentage of men in the ‘self-justification’ group subsequently differed
dramatically in probability of reporting 2 or more acts of unsafe sex; 17%
compared to 41% for the poster group and 42% for the control.
Tags: sexual behavior / hot-cold gaps
Source: Gold (1994), ‘Why we need to rethink Aids
education for gay men’,
Nudge: A field experiment in 31 primary
schools in England & Wales tested the efficacy of incentives to
encourage healthy eating by
schoolchildren (n=664). Children’s consumption patterns were monitored for 6
weeks and an intervention was carried out in 2/3rds of the schools for 4 weeks.
Children who ate a portion of fruit & veg were rewarded with stickers and
small gifts. At the end of the week the stickers could be exchanged for
stationery or small toys. There were two incentive programs; (i) piece rate
incentives where kids got an extra reward for choosing more than 4 pieces of
fruit & veg and (ii) competitive incentives where kids got an extra reward
if they received more stickers than their peers.
authors monitored consumption one week before the 4 week intervention, during
the intervention itself, one week after and 6 months later.
were two main results. First, the incentives have heterogeneous effects,
particularly by age and gender. Younger kids and girls are more responsive to
competitive incentives, which are more effective overall. Piece rate incentives
worked adversely on younger kids. Secondly, most of the effects were
short-lived and did not persist once the incentives are removed. An important
exception is that those kids from lower SES backgrounds do benefit from
long-term effects, remaining 16% more likely to try fruit & veg after 6
Tags: incentives / healthy eating
Source: Belot et al (2013), 'Changing Eating Habits: A Field
Experiment in Primary Schools',
Nudge: The authors use a randomized
field experiment to test the efficacy of personalized information in letters
sent to seniors for Medicare Part D prescription drug plans in the U.S. The
control group was given the address of the Medicare Plan Finder website. The
treatment group received a letter with personalized cost information; information
which was readily available for free and widely advertised. This
additional step—providing the information rather than having consumers actively
access it—had an impact. Plan switching was 28% in the intervention group,
versus 17% in the control group, and the intervention caused an average decline
in predicted consumer cost of about $100 a year among letter recipients—roughly
5% of the cost in the comparison group.
Tags: salience / healthcare
Source: Kling et al (2012) 'Comparison Friction:
Experimental Evidence from Medicare Drug Plans', Quarterly Journal
Nudge: A RCT looked a situation where
residential electricity customers saw price increases, with households in the
treatment group receiving
high-frequency information displays that give information about usage and
prices. This lowering of information acquisition costs allows identification of
the marginal information effect. Households only experiencing price increases
reduce demand by 0-7% whereas those also exposed to information feedback reduce
by 8-22%, depending on the amount of advance notice.
Tags: energy usage
Source: Jessoe & Rapson (2012) 'Knowledge
is (Less) Power: Experimental Evidence from Residential Energy Use', NBER Working
Nudge: This paper reviewed 7 recent
studies on calorie labeling (of which 2 were considered good quality, 5
considered fair). Only two of the seven studies reported a statistically
significant reduction in calories purchased among consumers using
calorie-labeled menus. The current body of evidence suggests that calorie
labeling does not have the intended effect of decreasing calorie purchasing or
Tags: calorie labeling / food
Source: Swartz et al (2011), ‘Calorie menu labeling on
quick-service restaurant menus: an updated systematic review of the literature’, International Journal of
Behavioral Nutrition and Physical Activity
Nudge: The authors examine the efficacy
of shifting consumers towards zero calorie beverages. Three sites in the U.S.
received 5 interventions in the period Oct 2009-May 2010; (1) a 10% discount on
zero-calorie beverages, (2) the 10% discount + discount messaging, (3)
messaging comparing calorie information of sugar beverages with zero-calorie
alternatives, (4) messaging comparing exercise equivalent information and (5)
messaging comparing both calorie and exercise equivalent information. The main
outcome measure was daily sales of zero-cal and sugared beverages.
failed to demonstrate a consistent effect across interventions. Treatments (2)
and (3) had statistically significant effects: the former saw an increase in
purchases of zero-cal beverages, the latter saw an increase in sugar-beverage
Tags: beverage consumption / messaging
Source: Jue et al (2012), ‘The
impact of price discounts and calorie messaging on beverage consumption: a