Risk perceptions are central to many health behavior theories. However, the relationship between risk perceptions and behavior, muddied by instances of inappropriate assessment and analysis, often looks weak. A meta-analysis of eligible studies assessing the bivariate association between adult vaccination and perceived likelihood, susceptibility, or severity was conducted. Thirty-four studies met inclusion criteria (N = 15,988). Risk likelihood (pooled r = .26), susceptibility (pooled r = .24), and severity (pooled r = .16) significantly predicted vaccination behavior. The risk perception-behavior relationship was larger for studies that were prospective, had higher quality risk measures, or had unskewed risk or behavior measures. The consistent relationships between risk perceptions and behavior, larger than suggested by prior meta-analyses, suggest that risk perceptions are rightly placed as core concepts in theories of health behavior.

Vaccination is one of the great achievements of the 20th century, yet persistent public-health problems include inadequate, delayed, and unstable vaccination uptake. Psychology offers three general propositions for understanding and intervening to increase uptake where vaccines are available and affordable. The first proposition is that thoughts and feelings can motivate getting vaccinated. Hundreds of studies have shown that risk beliefs and anticipated regret about infectious disease correlate reliably with getting vaccinated; low confidence in vaccine effectiveness and concern about safety correlate reliably with not getting vaccinated. We were surprised to find that few randomized trials have successfully changed what people think and feel about vaccines, and those few that succeeded were minimally effective in increasing uptake. The second proposition is that social processes can motivate getting vaccinated. Substantial research has shown that social norms are associated with vaccination, but few interventions examined whether normative messages increase vaccination uptake. Many experimental studies have relied on hypothetical scenarios to demonstrate that altruism and free riding (i.e., taking advantage of the protection provided by others) can affect intended behavior, but few randomized trials have tested strategies to change social processes to increase vaccination uptake. The third proposition is that interventions can facilitate vaccination directly by leveraging, but not trying to change, what people think and feel. These interventions are by far the most plentiful and effective in the literature. To increase vaccine uptake, these interventions build on existing favorable intentions by facilitating action (through reminders, prompts, and primes) and reducing barriers (through logistics and healthy defaults); these interventions also shape behavior (through incentives, sanctions, and requirements). Although identification of principles for changing thoughts and feelings to motivate vaccination is a work in progress, psychological principles can now inform the design of systems and policies to directly facilitate action.

OBJECTIVE: Improving provider recommendations is critical to addressing low human papillomavirus (HPV) vaccination coverage. Thus, we sought to determine the effectiveness of training providers to improve their recommendations using either presumptive “announcements” or participatory “conversations.” METHODS: In 2015, we conducted a parallel-group randomized clinical trial with 30 pediatric and family medicine clinics in central North Carolina. We randomized clinics to receive no training (control), announcement training, or conversation training. Announcements are brief statements that assume parents are ready to vaccinate, whereas conversations engage parents in open-ended discussions. A physician led the 1-hour, in-clinic training. The North Carolina Immunization Registry provided data on the primary trial outcome: 6-month coverage change in HPV vaccine initiation (≥1 dose) for adolescents aged 11 or 12 years. RESULTS: The immunization registry attributed 17 173 adolescents aged 11 or 12 to the 29 clinics still open at 6-months posttraining. Six-month increases in HPV vaccination coverage were larger for patients in clinics that received announcement training versus those in control clinics (5.4% difference, 95% confidence interval: 1.1%–9.7%). Stratified analyses showed increases for both girls (4.6% difference) and boys (6.2% difference). Patients in clinics receiving conversation training did not differ from those in control clinics with respect to changes in HPV vaccination coverage. Neither training was effective for changing coverage for other vaccination outcomes or for adolescents aged 13 through 17 (n = 37 796). CONCLUSIONS: Training providers to use announcements resulted in a clinically meaningful increase in HPV vaccine initiation among young adolescents.

Reducing smoking prevalence is a top public health priority because smoking is the leading cause of preventable death globally.¹ Clinical approaches to smoking cessation, including nicotine replacement² and pharmacotherapy,³ and behavioral approaches, including counseling and financial incentives,⁴ are effective for the smokers that they reach.⁵ Policy approaches are also useful because even those with a small effect on a single person can have a large effect across the population.⁶ Policy approaches to discourage smoking initiation and encourage cessation include raising prices, clean indoor air laws, restricting tobacco marketing, and requiring warnings on cigarette packs.⁷