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Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs (2022)

Chapter: Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs

Suggested Citation:"Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs." National Academies of Sciences, Engineering, and Medicine. 2022. Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs. Washington, DC: The National Academies Press. doi: 10.17226/26545.
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MARCH 2022 INCREASING UPTAKE OF COVID-19 VACCINATION THROUGH REQUIREMENT AND INCENTIVE PROGRAMS
Authors: Noel T. Brewer*
Alison Buttenheim**
Anica Law***
Saad B. Omer****
This rapid expert consultation was produced by the Societal Experts Action Network (SEAN), an activity of the National Academies of Sciences, Engineering, and Medicine that is sponsored by the National Science Foundation and the Alfred P. Sloan Foundation. SEAN links researchers in the social, behavioral, and economic sciences with decision makers to respond to policy questions arising from the COVID-19 pandemic. This project is a collaboration with the National Academies’ Standing Committee on Emerging Infectious Diseases and 21st Century Health Threats, which is sponsored by the U.S. Department of Health and Human Services, Office of the Assistant Secretary for Preparedness and Response.
SEAN is interested in your feedback. Was this rapid expert consultation useful? For further inquiries regarding this rapid expert consultation or to send comments, contact sean@nas.edu or (202) 334-3440.

* Gillings Distinguished Professor in Public Health, Gillings School of Global Public Health, University of North Carolina

** Associate Professor of Nursing and Health Policy, University of Pennsylvania

*** Assistant Professor, Boston University School of Medicine

**** Director, Yale Institute for Global Health

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Suggested Citation:"Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs." National Academies of Sciences, Engineering, and Medicine. 2022. Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs. Washington, DC: The National Academies Press. doi: 10.17226/26545.
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EXECUTIVE SUMMARY

As the COVID-19 pandemic enters its third year, the emergence of highly transmissible variants has elevated the urgency of increasing vaccine uptake. Increases in COVID-19 cases, hospitalizations, and deaths in the United States among the unvaccinated reinforce the importance of vaccinating large portions of the population. Accordingly, decision makers nationwide have been implementing various interventions, such as COVID-19 vaccine requirement and incentive programs for specific populations, to increase vaccine uptake. It is important to stress that such programs need to address equitable access to vaccines. Further, while incentives have not proven consistently to be effective in the United States as a means of promoting uptake of first doses of the COVID-19 vaccines, they may have potential for impact if used for booster doses.

This rapid expert consultation draws on existing social, behavioral, and economic science research to identify actionable guidance for state and local decision makers engaged in designing COVID-19 vaccine requirement and incentive programs. This guidance comprises the key design considerations listed in Box 1.

Suggested Citation:"Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs." National Academies of Sciences, Engineering, and Medicine. 2022. Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs. Washington, DC: The National Academies Press. doi: 10.17226/26545.
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INTRODUCTION

As the COVID-19 pandemic moves into its third year in the United States, the emergence of the highly transmissible omicron variant—which as of the week ending January 15, 2022, accounted for 99.5 percent of new COVID-19 cases1—and the potential for additional variants to appear in the future point to the urgency of continuing to increase vaccine uptake. The omicron variant has also highlighted the importance of high uptake of booster doses among vaccinated people.2 Yet while initial COVID-19 vaccination efforts were successful in getting large numbers of people vaccinated relatively rapidly, the percentage of the population that is vaccinated remains suboptimal3 (Ndugga et al., 2022). Vaccine hesitancy across various demographic groups, combined with the spread of misinformation and disinformation through social and other media and ongoing barriers to access, has contributed to the stalling of vaccinations (NASEM, 2021a,b; Viswanath et al., 2021). The net result is suboptimal vaccination coverage that varies greatly across regions and population subgroups.4 Efforts to increase vaccine uptake have included removing barriers to access, distributing vaccines equitably, providing incentives, requiring vaccination for access to certain venues, and implementing messaging strategies targeting different groups (Dai et al., 2021; Gonzales et al., 2021; Law et al., 2021; Mazar et al., 2022; Rutten et al., 2021; Viswanath et al., 2021; Walkey, Law, and Bosch, 2021).

Previous rapid expert consultations from the National Academies5 have provided guidance on implementing communication strategies to improve understanding of vaccine efficacy, effectiveness, and safety; communicating about variants and childhood vaccinations;

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1 See https://www.cdc.gov/coronavirus/2019-ncov/covid-data/covidview/index.html.

2 See https://www.cdc.gov/coronavirus/2019-ncov/vaccines/stay-up-to-date.html?CDC_AA_refVal=https%3A%2F%2Fwww.cdc.gov%2Fcoronavirus%2F2019-ncov%2Fvaccines%2Ffully-vaccinated.html.

3 The vaccination rates for the United States as of December 5, 2021, were 59.9 percent fully vaccinated and 71 percent with at least one dose; as of January 31, 2022, the respective proportions were 63.8 and 75.9 percent. See https://www.mayoclinic.org/coronavirus-covid-19/vaccine-tracker.

4 As of January 22, 2022, for example, 49 percent of the eligible population in Alabama was fully vaccinated, compared with 79 percent of the eligible population in Vermont. See https://www.mayoclinic.org/coronavirus-covid-19/vaccine-tracker. The Centers for Disease Control and Prevention (CDC) defines “fully vaccinated” as having two shots of the Moderna or Pfizer-BioNTech vaccination or one dose of the Johnson & Johnson vaccine as per CDC guidelines. See https://www.cdc.gov/coronavirus/2019-ncov/vaccines/stay-up-to-date.html?CDC_AA_refVal=https%3A%2F%2Fwww.cdc.gov%2Fcoronavirus%2F2019-ncov%2Fvaccines%2Ffully-vaccinated.html.

5 These rapid expert consultations include Strategies for Building Confidence in the COVID-19 Vaccines; Understanding and Communicating about COVID-19 Vaccine Efficacy, Effectiveness, and Equity; and Communication Strategies for Building Confidence in COVID-19 Vaccines: Addressing Variants and Childhood Vaccinations.

Suggested Citation:"Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs." National Academies of Sciences, Engineering, and Medicine. 2022. Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs. Washington, DC: The National Academies Press. doi: 10.17226/26545.
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and building confidence in the COVID-19 vaccines. The key messages of one of these rapid expert consultations, Communication Strategies for Building Confidence in COVID-19 Vaccines: Addressing Variants and Childhood Vaccinations, are summarized in Box 2.

This rapid expert consultation draws on the fields of behavioral economics, health behavior, risk communication, and psychology to inform efforts to increase uptake of COVID-19 vaccines using two of the strategies listed above—namely, requirement6 and incentive programs.7 It describes key aspects of the current COVID-19 landscape (the omicron variant, authorization and approval of vaccines for adults and children, and the availability of boosters) and details considerations that may be useful in designing such programs to increase vaccine uptake.

THE CURRENT COVID-19 LANDSCAPE

Despite early vaccination successes, which achieved rates of adult vaccination higher than those for any other disease within a similarly brief period of time, the evolving COVID-19 pandemic continues to pose a public health risk. The disease remains one of the leading causes of death in all age groups.8 Other major public health implications of an uncontrolled, ongoing

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6 In this rapid expert consultation, the term “requirement” is used to include compulsory vaccination laws and mandates.

7 The full statement of task states: “The National Academies of Sciences, Engineering, and Medicine will produce a rapid expert consultation to assist decision makers in increasing uptake of COVID-19 vaccines in light of the evolving pandemic. Drawing from research on science and risk communication, decision-making, behavioral economics, and social psychology, this document will identify actionable guidance and best practices that state and local government decision-makers can use when designing approaches to increase the uptake of COVID-19 vaccines such as incentives, mandates, and addressing disincentives. This document will be designed to be of practical use to decision makers, but will not recommend specific actions or include other recommendations. It will be reviewed in accordance with institutional guidelines.”

8 See https://www.healthsystemtracker.org/brief/covid-19-leading-cause-of-death-ranking.

Suggested Citation:"Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs." National Academies of Sciences, Engineering, and Medicine. 2022. Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs. Washington, DC: The National Academies Press. doi: 10.17226/26545.
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pandemic include (1) risks to vulnerable people who either cannot be vaccinated or cannot mount a sufficient immune response to a vaccine (Preskorn, 2020); (2) societal disruptions, such as interruption of school and work (Dibner, Schweingruber, and Christakis, 2020; Leroy, Schmidt, and Madjar, 2021); (3) overwhelmed health care systems that impede care for non–COVID-19 patients (Hassan and Mahmoud, 2021); (4) mental trauma and bereavement due to the death of loved ones (Slomski, 2021; Verdery et al., 2020); and (5) the ongoing risk that mutation of the SARS-CoV-2 virus will lead to new variants (Sah et al., 2021).

In the context of newly emerging variants, those who are unvaccinated and not recently infected continue to be at far higher risk of adverse outcomes from COVID-19 relative to those who are vaccinated. According to the Centers for Disease Control and Prevention (CDC) (2022a), as of January 2022, unvaccinated adults aged 18 and older and 12- to 17-year-olds, respectively, were 7 times and 3 times more likely to be hospitalized than their fully vaccinated counterparts. The data also show the positive impact of booster doses, as unvaccinated adults aged 18 and older had a 9 times higher risk of being hospitalized with COVID-19 compared with their fully vaccinated and boosted peers (CDC, 2022a). Among adults aged 65 and older, the unvaccinated were 15 times more likely to be hospitalized than those who were fully vaccinated and had received a booster dose (CDC, 2022a).

Additional CDC data show that within all age groups, unvaccinated people have higher case and death rates (CDC, 2022b). As of January 2022, for example, unvaccinated versus vaccinated adults aged 18 and older had almost 3 times the risk of testing positive for COVID-19 (CDC, 2022b). As of December 2021, unvaccinated versus vaccinated adults aged 18 and older had 41 times the risk of dying from COVID-19 (CDC, 2022b).

According to the Kaiser Family Foundation’s COVID-19 Vaccine Monitor (February, 2022), which measures vaccination intention,9 77 percent of adult respondents said they had already been vaccinated, 16 percent said they would definitely not get vaccinated, 4 percent said they would wait and see, 3 percent said they would get vaccinated if doing so were required, and only 1 percent said they would get vaccinated as soon as possible.10 Among respondents who had not yet been vaccinated, 6 in 10 were under age 50, 6 in 10 identified as Republican or lean Republican, and 5 in 10 had a high school education or less.11 Tailoring requirement and incentive programs to address the underlying reasons for hesitancy or procrastination across groups could increase vaccine uptake. For incentive programs, understanding the target population and the purpose of the incentives can help in determining how best to design, implement, and frame them. For example, incentives can be framed as inducements, designed to convey that vaccination has significant benefits (Brewer, 2021). Incentives can also be framed as compensation for the costs of getting vaccinated (e.g., lost income, time off from work, and child care expenses) (Volpp and Cannuscio, 2021). These two framings can both be effective under different conditions and may differ in their impact on long-term outcomes (e.g., trust, relationships with the health care system).

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9 While measurement of vaccine intention can provide some useful information, it is limited in predicting actual behavior, and results need to be interpreted with caution.

10 See https://www.kff.org/coronavirus-covid-19/dashboard/kff-covid-19-vaccine-monitor-dashboard.

11 See https://www.kff.org/coronavirus-covid-19/dashboard/kff-covid-19-vaccine-monitor-dashboard/#uptake.

Suggested Citation:"Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs." National Academies of Sciences, Engineering, and Medicine. 2022. Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs. Washington, DC: The National Academies Press. doi: 10.17226/26545.
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DESIGN CONSIDERATIONS FOR INCREASING UPTAKE OF COVID-19 VACCINES THROUGH REQUIREMENT AND INCENTIVE PROGRAMS

Vaccine requirement programs function by requiring or mandating vaccination for such purposes as work, travel, attending school, and visiting restaurants or entertainment venues. Vaccine incentive programs provide a reward for getting vaccinated; the reward may be monetary or nonmonetary and may either be guaranteed or offer the chance to win something of value (e.g., via a lottery). Communication efforts aimed at educating the public and increasing accessibility are usually a first step in public health strategies for promoting wider adoption of particular behaviors. Examples of such efforts include content placed in traditional media, public health and governmental communications, and formal communication campaigns targeting specific segments of the population using trusted messengers (NASEM, 2021b; Salmon et al., 2021). While these efforts need to continue, requirement programs can serve as an additional tool for targeting those who remain unvaccinated, while if properly designed, incentive programs may be helpful for targeting vaccinated individuals who have not yet received a booster dose. Often these strategies intersect, and complementary efforts involving the two types of interventions are needed.

Requirement and incentive programs may be particularly helpful when people’s stated intentions suggest a desire to remain unvaccinated, or when people indicate that they intend to get vaccinated but have not yet taken action to do so. Requirements and incentives can increase vaccine uptake by changing the cost/benefit calculus of the decision (Brewer, 2021; Building Trust and Battling Barriers: The Urgent Need to Overcome Vaccine Hesitancy, 2021). A major unanswered question remains as to which hesitant groups, and under which conditions, are responsive to requirement or incentive programs. While this issue goes beyond the scope of this rapid expert consultation, the importance of understanding the context of the targeted population is emphasized below (see Salali and Uysal, 2021, for more discussion).

As with ongoing communication efforts, however, designing successful requirement and incentive programs depends on the target population, desired outcomes, and political realities. Increasing access to vaccination is also critical because requirement and incentive programs will be much less effective if vaccines are not readily available. Research has shown the importance of addressing such barriers to access such as: (1) structural barriers, including the cost of visiting the vaccine site, the administrative burdens of registering and accessing the vaccines, barriers to physical access (including geographic and functional proximity to vaccines), limited job flexibility, and supply chain disruptions and (2) attitude barriers, including low perceived risks of contracting COVID-19, lack of trust in vaccines, misinformation or disinformation about vaccines, and costs (Gonzales et al., 2021; Mazar et al., 2022; Rutten et al., 2021; Viswanath et al., 2021). Some strategies for increasing access are discussed in Box 3.

Suggested Citation:"Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs." National Academies of Sciences, Engineering, and Medicine. 2022. Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs. Washington, DC: The National Academies Press. doi: 10.17226/26545.
×
Suggested Citation:"Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs." National Academies of Sciences, Engineering, and Medicine. 2022. Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs. Washington, DC: The National Academies Press. doi: 10.17226/26545.
×

Development of Vaccine Requirement Programs

Historically, vaccine requirement programs have been used to determine access to work and school, and they have been effective in increasing vaccination rates for targeted populations (Hill et al., 2015; Lytras et al., 2016; Omer et al., 2006a; Phadke et al., 2016). In the United States, targeted requirements for vaccination have historically sustained high immunization coverage for such diseases as measles, pertussis, and chicken pox (Hill et al., 2015; Omer et al., 2006; Phadke et al., 2016). A prepandemic review exploring psychological principles with respect to vaccination in general found that vaccination requirements were more likely to affect vaccination rates relative to interventions aimed at changing how people think and feel about vaccination (Brewer et al., 2017).

Other prepandemic work has explored mandatory vaccinations in relation to the seasonal influenza vaccine. One review of studies evaluating interventions aimed at increasing coverage of that vaccine among health care workers found that mandatory vaccination was the most effective compared with declination statements,12 increased awareness, and increased access (Lytras et al., 2016).13 Other studies have likewise shown the effectiveness of mandatory seasonal influenza vaccination policies among health care workers in the United States, which have achieved vaccination rates as high as 98 percent following the introduction of a vaccination requirement (Babcock et al., 2010; Gaughan, 2010; Rakita et al., 2010).

The most common vaccine requirement programs have been those targeting school entry, which have proven effective in the United States (see, e.g., Attwell et al., 2018; Bednarczyk et al., 2019; Wang et al., 2014). A review of studies on childhood vaccination in high-income countries, including the United States, found that school vaccination requirements were highly successful in increasing vaccination rates (Community Preventive Services Task Force, 2016). A systematic review exploring the impact of mandatory vaccinations on pediatric vaccination coverage found that school entry mandates (especially for those aged 5–7) were associated with increased pediatric vaccination rates (Greyson, Vriesema-Magnuson, and Bettinger, 2019).14

One caveat is that this same review found that mandates for human papillomavirus (HPV) vaccination for girls in the United States were largely ineffective in increasing uptake (Greyson et al., 2019). Reasons for this failure include easy opt-out provisions in the mandates, the relatively low uptake at the time the policies were adopted, parental skepticism about the vaccine, public perception of HPV as a sexually transmitted infection not spread at school, and perceptions of corporate influence on the adoption of mandates for the vaccine (Barraza et al., 2016; Colgrove, Abiola, and Mellow, 2010; Dempsey et al., 2009; Intlekofer, Cunningham, and Caplan, 2012; Mays, Sturm, and Zimet, 2004). On the other hand, some studies suggest that HPV vaccine requirements may be effective for boys, as shown by an evaluation of such a program in Rhode Island (Ko et al., 2020).

The challenges associated with HPV vaccine mandates offer lessons for any future COVID-19 vaccine requirement program. These lessons include the need to gain the support of influential and trusted organizations, the value of compromises, the need to allow for sufficient time before requirements go into effect, and the importance of informing the public about the requirements and addressing the public’s concerns (Barraza et al., 2016; Schwartz et al., 2007).

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12 A declination statement is a legal document that signals an individual’s intent to refuse a recommended treatment, such as a requirement for vaccination of health care workers against influenza.

13 The review included 46 (18 U.S.-based) eligible studies from 1992 to 2015.

14 The systematic review included 18 U.S., 1 Italian, and 1 Australian studies from 1970 to 2017.

Suggested Citation:"Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs." National Academies of Sciences, Engineering, and Medicine. 2022. Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs. Washington, DC: The National Academies Press. doi: 10.17226/26545.
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In addition, the available literature emphasizes the need for care in developing vaccine requirements so “that policies don’t inadvertently entrench inequity or fuel anti-vaccine activism” (Omer, Betsch, and Leask, 2019, p. 470). Box 4 summarizes some of these design considerations, which are discussed in further detail below.

Public health and ethical considerations have been applied

From an ethical viewpoint, the least intrusive but effective method for increasing vaccination has been shown to be optimal (Jecker, 2021). Ideally, vaccination requirements would be implemented only after other strategies for increasing vaccine uptake (including communications and removal of access barriers) had been exhausted. In addition, “principles of public health law and ethics require that interventions that impinge on autonomy be reasonable and necessary” (Mello, Silverman, and Omer, 2020, p. 1297).

Drawing on lessons from vaccination campaigns for the 1976 swine flu outbreak, the H1N1 influenza outbreak, smallpox, and HPV, ethicists have suggested the importance of meeting certain ethical criteria before introducing vaccine requirements (Mello, Silverman, and Omer, 2020). These criteria include the following: (1) other mitigation strategies have not worked; (2) the CDC’s Advisory Committee on Immunization Practices has recommended vaccination for the groups the requirement will cover; (3) vaccine supply is sufficient to cover these groups; (4) evidence for the vaccine’s safety and efficacy has been communicated transparently; (5) vaccination is easily accessible, with any barriers removed; (6) compensation is provided for those who may need it to take time away from work or child care; (7) real-time surveillance is provided for vaccine side effects; and (8) voluntary uptake among high-priority groups has not reached levels sufficient to obviate the need for increased vaccination (Mello, Silverman, and Omer, 2020).

Requirements are balanced

The how, why, and when of enforcement of vaccine requirement programs merit careful consideration. Research on previous such programs has shown that their design needs to balance excessive leniency, which allows people to exempt themselves easily, and excessive strictness, which disallows any exemption at all (Brewer et al., 2017). There is not a “simple linear

Suggested Citation:"Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs." National Academies of Sciences, Engineering, and Medicine. 2022. Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs. Washington, DC: The National Academies Press. doi: 10.17226/26545.
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relationship between the forcefulness of a policy and its impact on the rate of vaccination” (Omer, Betsch, and Leask, 2019, p. 470). In reviewing the available data on childhood vaccinations from Washington State and California, for example, these researchers concluded that a middle-of-the-road approach whereby requirements are strict but leave room for exemptions may be most effective. They emphasize that balance is important because while requirements can increase vaccine uptake in the short term, the limitations on personal choice may lead to resistance or distrust with respect to future public health interventions (Shachar and Reiss, 2020).

Research predating the COVID-19 pandemic shows that the effectiveness of a mandate program can be linked to the ease or difficulty of obtaining religious or philosophical exemptions (Delamater et al., 2019; Omer et al., 2018; Wang et al., 2014). Specifically, this research found that mandates that allowed for exemptions but made those exemptions difficult to obtain potentially limited their use among individuals with sincerely held beliefs (Omer et al., 2018; Jones et al., 2018). In the context of COVID-19, finding this balance is important so as to not promote antivaccination sentiments.

Requirements are targeted

Requirements are more likely to be enforceable if they are targeted to specific groups (for example, hospital workers and schoolchildren) and not levied on the population at large. Moreover, ethics scholars have argued that targeting mandatory vaccinations to specific subgroups or circumstances (e.g., those who wish to dine indoors or go unmasked in public indoor spaces) is preferable to targeting whole populations (Savulescu, Pugh, and Wilkinson, 2021).

Targeted requirements for schools and institutions of higher education, individual employers, hospitals, nursing homes, indoor dining, and museum visitation, among others, can be successful in raising vaccination rates. As discussed above, research exploring the effect of vaccine requirements for routine childhood immunizations has shown that the requirements can lead to both short- and long-term increases in vaccine uptake in the targeted groups (Lee and Robinson, 2016). Likewise, targeted workplace vaccination requirements have been successful in increasing coverage for the influenza vaccine by up to 25 percent (Schumacher et al., 2020).

Vaccine Booster Incentive Programs

A large body of literature suggests that incentive programs can increase healthy behaviors, such as medication adherence among individuals at elevated risk of cardiovascular disease (Asch et al., 2015; Barankay et al., 2020) and uptake of seasonal influenza vaccine among college students (Bronchetti, Huffman, and Magenheim, 2015). The CDC’s Community Guide to Preventive Services recommends use of financial incentives to increase vaccine uptake, although the evidence supporting this recommendation predates the pandemic (Jacob et al., 2016).

Several studies using patient-level data have found that financial incentives increased uptake of COVID-19 vaccines when they were first available (Barber and West, 2022; Campos-Mercade et al., 2021; Wong et al., 2022). However, other research on incentive programs, typically using ecological designs to evaluate lotteries, have shown a lack of efficacy (see, e.g., Chang et al., 2021; Dave et al., 2021; Law et al., 2021; Milkman et al., 2021; Thirumurthy et al., in press; Walkey, Law, and Bosch, 2021). In some cases, incentives for first doses of COVID-19

Suggested Citation:"Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs." National Academies of Sciences, Engineering, and Medicine. 2022. Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs. Washington, DC: The National Academies Press. doi: 10.17226/26545.
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vaccines may even have backfired (Chang et al., 2021). Taken together, these conflicting findings show that a positive impact from incentive programs for COVID-19 vaccination is far from guaranteed.

A natural question is what might make financial incentives most effective at promoting uptake of COVID-19 vaccine boosters. Incentives for boosters may have greater potential for impact relative to those for first doses, given that the population in need of boosting has already demonstrated a willingness to be vaccinated and is therefore likely to be more open to receiving another dose given the right reason for doing so. The discussion that follows includes best practices that may be useful to consider when offering incentives for boosters.

The general literature on incentives suggests that they can be an effective tool for persuading difficult-to-reach groups. However, the behavior changes thereby induced typically persist only as long as the incentive is offered and do not last beyond the conclusion of the incentive program (Cahill and Perera, 2008; Marteau, Ashcroft, and Oliver, 2009; Sutherland, Christianson, and Leatherman, 2008). In their review, Fisher and colleagues (2011, p. 332) conclude that incentives are highly recommended for increasing (1) key behaviors that need to occur only once or relatively infrequently versus ongoing behaviors, or (2) the likelihood of behaviors in particular settings or during particularly crucial time periods.

The discussion here draws on principles from psychological research on incentives to offer insights into how incentives for boosters could be implemented effectively and ethically. In general, although financial incentives have proven to be a useful persuasion tactic for purposes other than promoting COVID-19 vaccination, their effectiveness depends on the nature of the behavior being encouraged, the size of the incentive, the population involved, and the social and political context (Thirumurthy, Asch, and Volpp, 2019). Despite the complex decision making related to such programs, the available literature points to some key design considerations that may improve the effectiveness of financial incentive programs for encouraging COVID-19 booster shots. These considerations are discussed below and summarized in Box 5.

Suggested Citation:"Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs." National Academies of Sciences, Engineering, and Medicine. 2022. Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs. Washington, DC: The National Academies Press. doi: 10.17226/26545.
×

The incentive is known and well-advertised

As with other vaccination efforts, targeted communication is important for booster incentive programs. Examples of marketing strategies that have been used in incentive programs include ads in social media and other digital media, press releases, and local television coverage. Widely advertising incentives also can increase public knowledge about the importance of vaccination. Moreover, it can provide a public justification for getting vaccinated among people who in the past have been vaccine hesitant, generating a sense that “everyone else must be getting vaccinated now” and changing the perceived social norm, which in turn can change behavior (Cialdini, 1991).

The incentive is delivered immediately

Psychological and economic research shows that rewards are most effective when they are distributed immediately (Lattal, 1987; Woolley and Fishbach, 2018) because people tend to discount anything they must wait to receive (Laibson, 1997; O’Donoghue and Rabin, 2015; Woolley and Fishbach, 2018). Receiving rewards immediately also adds to the positive experience of taking a rewarded action. To this end, people could receive gift cards or other incentives at the vaccination site.

The incentive is valued

Designing successful incentives requires understanding what is valued among the target population (Brewer et al., 2017). Prior research on incentives for health behaviors has found that larger rewards are typically associated with more positive behaviors, such as treatment adherence (Jones et al., 2000; Lussier et al., 2006). Research also has shown that cash incentives are more effective than such equally valuable nonmonetary incentives as grocery coupons, bus tokens, fast-food coupons, and vouchers (Petry et al., 2005), as cash can be used to purchase whatever a person values most.

Some researchers have attempted to explore what amount of a cash incentive is enough when it comes to encouraging COVID-19 vaccination. One study of COVID-19 vaccination found that a hypothetical payment of $100 was more likely than a payment of $20 to increase people’s stated intentions to receive a COVID-19 vaccine (Serra-Garcia and Szech, 2021). On the other hand, another study that explored whether respondents said they would get vaccinated under one of three financial incentive conditions ($1000, $1500, or $2000) or a no-incentive condition found that the size of the cash incentive did not really affect the reported uptake rates (Robertson, Schaefer, and Scheitrum, 2021). Noncash incentives are especially prone to wide variation in the value people assign to them. For example, a hunting license is a popular incentive for many rural residents in West Virginia but is likely to hold less value for a university population.

The incentive is cost-effective

The decision to use a particular financial incentive for COVID-19 vaccination programs needs to depend on cost-effectiveness analysis and the availability of other, more cost-effective strategies. In the past, for example, incentive programs employing lotteries have proven to be particularly cost-effective in motivating health behaviors because individuals tend to overestimate their chances of winning. As a result, these incentives are more cost-effective than guaranteed payments when budgets cannot support such payments that are meaningfully large (Camerer, 2011; Patel et al., 2018; Volpp et al., 2008). Research shows, however, that

Suggested Citation:"Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs." National Academies of Sciences, Engineering, and Medicine. 2022. Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs. Washington, DC: The National Academies Press. doi: 10.17226/26545.
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guaranteed incentives may be more effective overall in changing behavior when their value to the target population is nontrivial (Brewer et al., 2017).

The incentive meets ethical and health equity criteria

Ethicists have justified the use of incentives based on the principles of (1) decreasing overall harm from COVID-19 by reducing its spread, and thus protecting people who are not yet vaccinated and those for whom the vaccines have limited efficacy; (2) reducing the burden on health care systems; and (3) protecting disadvantaged populations that have faced greater barriers to accessing vaccination and could experience worse outcomes if infected (Persad and Emmanuel, 2021). At the same time, however, ethicists have warned of the need to design incentive programs so as to ensure that they are not coercive, particularly for low-income people who may be forced to accept an incentive because of their economic circumstances (Largent and Miller, 2021). Even modest cash awards could constitute unfair inducement for those who are the least well-off, and race-related differences in wealth could compound this effect for some groups (Jecker, 2021). Awards that are too small may also be exploitive among groups that have historically faced inequities (Largent and Miller, 2021). Incentive programs need to build trust and to be transparent and clear.

The potential risks of implementing the incentive program are carefully weighed

It is important to consider certain risks when designing and implementing an incentive program. First, people may come to expect payment for any future vaccination. Indeed, a meta-analysis of experimental studies found that once a behavior has been associated with an incentive, people may be less willing to engage in it again without further incentives (Mantzari, Vogt, and Marteau, 2014). Second, people may construe the incentive as compensation for a potential risk associated with the vaccine (Cryder et al., 2010), which can adversely affect other outcomes, such as trust and perceptions of vaccine efficacy. Finally, incentives that are posed as rewards for vaccination run the risk of being economically inefficient if they end up being used to reward those who would have gotten vaccinated anyway (Buttenheim and Asch, 2013). At present, these risks are largely hypothetical and not based in empirical findings; nonetheless, it is important for incentives programs to take them into account.

CONCLUSION

The continuing pandemic has necessitated the use of additional approaches to increase the uptake of COVID-19 vaccines. Requirement programs can be an effective strategy for increasing rates of vaccination, but their success depends on designing them in ways that are targeted, effective, and build trust. While evidence that incentives can improve first-dose vaccine uptake is limited, incentives may be able to move the needle on booster uptake, especially for people already inclined toward vaccination and early on in the rollout of new boosters.

SEAN is interested in your feedback. Was this rapid expert consultation useful? Send comments to sean@nas.edu or (202) 334-3440.

Suggested Citation:"Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs." National Academies of Sciences, Engineering, and Medicine. 2022. Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs. Washington, DC: The National Academies Press. doi: 10.17226/26545.
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Suggested Citation:"Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs." National Academies of Sciences, Engineering, and Medicine. 2022. Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs. Washington, DC: The National Academies Press. doi: 10.17226/26545.
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Suggested Citation:"Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs." National Academies of Sciences, Engineering, and Medicine. 2022. Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs. Washington, DC: The National Academies Press. doi: 10.17226/26545.
×

ACKNOWLEDGMENTS

We thank the sponsors of SEAN—the National Science Foundation and the Alfred P. Sloan Foundation—and of the Standing Committee on Emerging Infectious Diseases and 21st Century Health Threats—the U.S. Department of Health and Human Services, Assistant Secretary for Preparedness and Response.

Special thanks go to the members of the SEAN executive committee, who dedicated time and thought to this project: Mary T. Bassett (co-chair), New York State Department of Health; Robert M. Groves (co-chair), Georgetown University; Dolores Acevedo-Garcia, Brandeis University; Mahzarin R. Banaji, Harvard University; Dominique Brossard, University of Wisconsin–Madison; Janet Currie, Princeton University; Michael Hout, New York University; Maria Carmen Lemos, University of Michigan; Adrian E. Raftery, University of Washington; and Wendy Wood, University of Southern California. We thank as well the Standing Committee on Emerging Infectious Diseases and 21st Century Health Threats, particularly Harvey Fineberg (Gordon and Betty Moore Foundation).

We extend gratitude to the staff of the National Academies, in particular to Emily P. Backes, Malvern T. Chiweshe, Chelsea Fowler, and Shalini Singaravelu, who contributed research, editing, and writing assistance. We thank Dara Shefska and Mary Ghitelman, who led communication and dissemination for the project. Thanks are also due to Elizabeth Tilton who managed the administrative aspects of the project and assisted with report production. From the Division of Behavioral and Social Sciences and Education, we thank Kirsten Sampson Snyder, who shepherded the report through the review process. We thank as well Rona Briere and Allie Boman for their skillful editing.

To supplement their own expertise, the authors received input from several external sources, whose willingness to share their perspectives and expertise was essential to this work. We thank: Hengchen Dai, University of California, Los Angeles; Jamie Druckman, Northwestern University; W. Douglas Evans, The George Washington University; Robert Hornik, University of Pennsylvania; Nancy S. Jecker, University of Washington; Katherine Milkman, University of Pennsylvania; Alex Rothman, University of Minnesota; Dietram Scheufele, University of Wisconsin–Madison; Elisa Sobo, San Diego State University; Kevin Volpp, University of Pennsylvania; Robb Willer, Stanford University; and Itzhak Yanovitzky, Rutgers University.

We also thank the following individuals for their review of this rapid expert consultation: William J. Congdon, Economic Studies, Brookings Institution; Karen S. Cook, Department of Sociology, Stanford University; LaQuandra S. Nesbitt, Department of Health, Washington, D.C.; Amelie G. Ramirez, Department of Population Health Sciences and Institute for Health Promotion Research, University of Texas Health San Antonio; and Timothy D. Wilson, Department of Psychology, University of Virginia.

Although the reviewers listed above provided many constructive comments and suggestions, they were not asked to endorse the conclusions of this document, nor did they see the final draft before its release. The review of this document was overseen by Alicia L. Carriquiry, Department of Statistics, Iowa State University, and Robert A. Moffitt, Department of Economics, The Johns Hopkins University. They were responsible for making certain that an independent examination of this rapid expert consultation was carried out in accordance with the standards of the National Academies and that all review comments were carefully considered. Responsibility for the final content rests entirely with the authors and the National Academies.

Suggested Citation:"Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs." National Academies of Sciences, Engineering, and Medicine. 2022. Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs. Washington, DC: The National Academies Press. doi: 10.17226/26545.
×

SOCIETAL EXPERTS ACTION NETWORK (SEAN) EXECUTIVE COMMITTEE

MARY T. BASSETT (Co-chair), New York State Department of Health

ROBERT M. GROVES (Co-chair), Georgetown University

DOLORES ACEVEDO-GARCIA, Brandeis University

MAHZARIN R. BANAJI, Harvard University

DOMINIQUE BROSSARD, University of Wisconsin–Madison

JANET CURRIE, Princeton University

MICHAEL HOUT, New York University

MARIA CARMEN LEMOS, University of Michigan

ADRIAN E. RAFTERY, University of Washington

WENDY WOOD, University of Southern California

Staff:

EMILY P. BACKES, Senior Program Officer

MALVERN T. CHIWESHE, Program Officer

CHELSEA FOWLER, Associate Program Officer

DARA SHEFSKA, Communications Specialist (until February 2022)

ELIZABETH TILTON, Senior Program Assistant

Suggested Citation:"Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs." National Academies of Sciences, Engineering, and Medicine. 2022. Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs. Washington, DC: The National Academies Press. doi: 10.17226/26545.
×

STANDING COMMITTEE ON EMERGING INFECTIOUS DISEASES AND 21ST CENTURY HEALTH THREATS

HARVEY FINEBERG (Chair), Gordon and Betty Moore Foundation

KRISTIAN ANDERSEN, The Scripps Research Institute

RALPH STEVEN BARIC, University of North Carolina at Chapel Hill

MARY T. BASSETT, New York State Department of Health

GEORGES BENJAMIN, American Public Health Association

DONALD BERWICK, Institute for Healthcare Improvement

RICHARD BESSER, Robert Wood Johnson Foundation

R. ALTA CHARO, University of Wisconsin Law School

PETER DASZAK, EcoHealth Alliance

JEFFREY S. DUCHIN, University of Washington

ELLEN EMBREY, Stratitia, Inc.

BARUCH FISCHHOFF, Carnegie Mellon University

DIANE GRIFFIN, Johns Hopkins Bloomberg School of Public Health

GIGI GRONVALL, Johns Hopkins Bloomberg School of Public Health

ROBERT GROVES, Georgetown University

MARGARET HAMBURG, Foreign Associate, National Academy of Medicine

DAN HANFLING, In-Q-Tel

JOHN HICK, Hennepin County Medical Center

KENT E. KESTER, International AIDS Vaccine Initiative

PATRICIA KING, Georgetown University Law Center

NICOLE LURIE, Coalition for Epidemic Preparedness Innovations

JONNA MAZET, University of California, Davis, School of Veterinary Medicine

PHYLLIS MEADOWS, The Kresge Foundation

TARA O’TOOLE, In-Q-Tel

ALEXANDRA PHELAN, Georgetown University

DAVID RELMAN, Stanford University

MARK SMOLINSKI, Ending Pandemics

DAVID WALT, Harvard Medical School

Project Staff

LISA BROWN, Senior Program Officer

EMMA FINE, Associate Program Officer

SHALINI SINGARAVELU, Associate Program Officer

MARGARET MCCARTHY, Research Associate

JULIE PAVLIN, Director, Board on Global Health

ANDREW M. POPE, Senior Director, Board on Health Sciences Policy

Suggested Citation:"Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs." National Academies of Sciences, Engineering, and Medicine. 2022. Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs. Washington, DC: The National Academies Press. doi: 10.17226/26545.
×
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Suggested Citation:"Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs." National Academies of Sciences, Engineering, and Medicine. 2022. Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs. Washington, DC: The National Academies Press. doi: 10.17226/26545.
×
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Suggested Citation:"Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs." National Academies of Sciences, Engineering, and Medicine. 2022. Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs. Washington, DC: The National Academies Press. doi: 10.17226/26545.
×
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Suggested Citation:"Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs." National Academies of Sciences, Engineering, and Medicine. 2022. Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs. Washington, DC: The National Academies Press. doi: 10.17226/26545.
×
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Suggested Citation:"Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs." National Academies of Sciences, Engineering, and Medicine. 2022. Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs. Washington, DC: The National Academies Press. doi: 10.17226/26545.
×
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Suggested Citation:"Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs." National Academies of Sciences, Engineering, and Medicine. 2022. Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs. Washington, DC: The National Academies Press. doi: 10.17226/26545.
×
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Suggested Citation:"Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs." National Academies of Sciences, Engineering, and Medicine. 2022. Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs. Washington, DC: The National Academies Press. doi: 10.17226/26545.
×
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Suggested Citation:"Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs." National Academies of Sciences, Engineering, and Medicine. 2022. Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs. Washington, DC: The National Academies Press. doi: 10.17226/26545.
×
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Suggested Citation:"Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs." National Academies of Sciences, Engineering, and Medicine. 2022. Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs. Washington, DC: The National Academies Press. doi: 10.17226/26545.
×
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Suggested Citation:"Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs." National Academies of Sciences, Engineering, and Medicine. 2022. Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs. Washington, DC: The National Academies Press. doi: 10.17226/26545.
×
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Suggested Citation:"Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs." National Academies of Sciences, Engineering, and Medicine. 2022. Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs. Washington, DC: The National Academies Press. doi: 10.17226/26545.
×
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Suggested Citation:"Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs." National Academies of Sciences, Engineering, and Medicine. 2022. Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs. Washington, DC: The National Academies Press. doi: 10.17226/26545.
×
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Suggested Citation:"Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs." National Academies of Sciences, Engineering, and Medicine. 2022. Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs. Washington, DC: The National Academies Press. doi: 10.17226/26545.
×
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Suggested Citation:"Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs." National Academies of Sciences, Engineering, and Medicine. 2022. Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs. Washington, DC: The National Academies Press. doi: 10.17226/26545.
×
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Suggested Citation:"Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs." National Academies of Sciences, Engineering, and Medicine. 2022. Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs. Washington, DC: The National Academies Press. doi: 10.17226/26545.
×
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Suggested Citation:"Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs." National Academies of Sciences, Engineering, and Medicine. 2022. Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs. Washington, DC: The National Academies Press. doi: 10.17226/26545.
×
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Suggested Citation:"Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs." National Academies of Sciences, Engineering, and Medicine. 2022. Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs. Washington, DC: The National Academies Press. doi: 10.17226/26545.
×
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Suggested Citation:"Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs." National Academies of Sciences, Engineering, and Medicine. 2022. Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs. Washington, DC: The National Academies Press. doi: 10.17226/26545.
×
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Suggested Citation:"Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs." National Academies of Sciences, Engineering, and Medicine. 2022. Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs. Washington, DC: The National Academies Press. doi: 10.17226/26545.
×
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Suggested Citation:"Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs." National Academies of Sciences, Engineering, and Medicine. 2022. Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs. Washington, DC: The National Academies Press. doi: 10.17226/26545.
×
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Suggested Citation:"Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs." National Academies of Sciences, Engineering, and Medicine. 2022. Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs. Washington, DC: The National Academies Press. doi: 10.17226/26545.
×
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Suggested Citation:"Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs." National Academies of Sciences, Engineering, and Medicine. 2022. Increasing Uptake of COVID-19 Vaccination Through Requirement and Incentive Programs. Washington, DC: The National Academies Press. doi: 10.17226/26545.
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