A 680,000-person megastudy of nudges to encourage vaccination in pharmacies

Encouraging vaccination is a pressing policy problem. To assess whether text-based reminders can encourage pharmacy vaccination and what kinds of messages work best, we conducted a megastudy. We randomly assigned 689,693 Walmart pharmacy patients to receive one of 22 different text reminders using a variety of different behavioral science principles to nudge flu vaccination or to a business-as-usual control condition that received no messages. We found that the reminder texts that we tested increased pharmacy vaccination rates by an average of 2.0 percentage points, or 6.8%, over a 3-mo follow-up period. The most-effective messages reminded patients that a flu shot was waiting for them and delivered reminders on multiple days. The top-performing intervention included two texts delivered 3 d apart and communicated to patients that a vaccine was “waiting for you.” Neither experts nor lay people anticipated that this would be the best-performing treatment, underscoring the value of simultaneously testing many different nudges in a highly powered megastudy

Differences in sensitivity to deviance partly explain ideological divides in social policy support

We propose that political differences in social policy support may be partly driven by the tendency for conservatives to show greater sensitivity to deviance than liberals, even among targets lacking social or functional relevance. In 3 studies, participants were shown geometric figures and were asked to identify the extent to which they were “triangles” (or circles, squares, etc.). More conservative participants reported greater differentiation between perfect and imperfect shapes than more liberal participants, indicating greater sensitivity to deviance. Moreover, shape differentiation partly accounted for the relationship between political ideology and social policy, partially mediating the link between conservatism and harsher punishment of wrongdoers (Studies 1 and 4), less support for public aid for disadvantaged groups (Study 2), and less financial backing for policies that benefit marginalized groups in society (Study 3). This effect was specific to policies that targeted deviant groups (Study 3) and who were not too highly deviant (Study 4). Results suggest that, in addition to commonly cited affective and motivational reactions to deviant actors, political differences in social policy may also be driven by conservatives’ greater cognitive propensity to distinguish deviance

A victim-centered approach to justice? Victim satisfaction effects on third-party punishments

Three studies investigated whether victims' satisfaction with a restorative justice process influenced third-party assignments of punishment. Participants evaluated criminal offenses and victims' reactions to an initial restorative justice conference, and were later asked to indicate their support for additional punishment of the offender. Across the three studies, we found that victim satisfaction (relative to dissatisfaction) attenuates people's desire to seek offender punishment, regardless of offense severity (Study 2) or conflicting reports from a third-party observer (Study 3). This relationship was explained by the informational value of victim satisfaction: Participants inferred that victims felt closure and that offenders experienced value reform, both of which elevated participants' satisfaction with the restorative justice outcome. The informational value communicated by victim satisfaction, and its criminal justice implications, are discussed

Megastudy shows that reminders boost vaccination but adding free rides does not

Encouraging routine COVID-19 vaccinations is likely to be a crucial policy challenge for decades to come. To avert hundreds of thousands of unnecessary hospitalizations and deaths, adoption will need to be higher than it was in the autumn of 2022 or 2023, when less than one-fifth of Americans received booster vaccines. One approach to encouraging vaccination is to eliminate the friction of transportation hurdles. Previous research has shown that friction can hinder follow-through and that individuals who live farther from COVID-19 vaccination sites are less likely to get vaccinated. However, the value of providing free round-trip transportation to vaccination sites is unknown. Here we show that offering people free round-trip Lyft rides to pharmacies has no benefit over and above sending them behaviourally informed text messages reminding them to get vaccinated. We determined this by running a megastudy with millions of CVS Pharmacy patients in the United States testing the effects of (1) free round-trip Lyft rides to CVS Pharmacies for vaccination appointments and (2) seven different sets of behaviourally informed vaccine reminder messages. Our results suggest that offering previously vaccinated individuals free rides to vaccination sites is not a good investment in the United States, contrary to the high expectations of both expert and lay forecasters. Instead, people in the United States should be sent behaviourally informed COVID-19 vaccination reminders, which increased the 30-day COVID-19 booster uptake by 21% (1.05 percentage points) and spilled over to increase 30-day influenza vaccinations by 8% (0.34 percentage points) in our megastudy. More rigorous testing of interventions to promote vaccination is needed to ensure that evidence-based solutions are deployed widely and that ineffective but intuitively appealing tools are discontinued