Since the start of the COVID-19 pandemic, the world’s hopes have been pinned on vaccines that have the potential to allow people to return to “life as normal” [1
]. The rollout of these vaccines is now well underway, with 2.3 billion people (29.6% of the world’s population) having received at least one dose at the time of writing. Some countries have already vaccinated the majority of their populations—for instance, 62.3% of Israel’s population are fully vaccinated, as is 57.3% of the UK’s population [2
These high proportions demonstrate that people in most countries, on the whole, have accepted the need for vaccines and are eager to get vaccinated [3
]. However, there remain some individuals who are reluctant to take the vaccine. In Israel, for example, 15% of the eligible adult population have not taken up the opportunity to get vaccinated [5
]. Likewise, 11% of eligible adults in the UK have not yet chosen to get vaccinated [6
]. Although these reluctant groups are relatively small, they are not insignificant—some estimates suggest that any vaccine refusal rate greater than 10% could significantly hinder herd immunity [1
]. Therefore, if we want to ensure enough people choose to get vaccinated to control the spread of the virus, it is vital that we understand the factors that affect people’s willingness to get vaccinated.
One important policy that might affect willingness to get vaccinated is vaccine passports. In order to allow vaccinated individuals to move freely and return to daily activities, several countries have introduced or considered measures that would restrict access to public spaces for people who are unvaccinated [7
]. The first country to implement such a policy was Israel. “Green passes” were provided from January 2021 onwards to fully vaccinated residents or people who had recovered from COVID-19, permitting entry to otherwise restricted sites such as gyms, restaurants, hotels, theatres, and music venues. In the US, New York required vaccine certification in order to access certain social activities, and many other states have also expressed interest in the idea [8
]. In Europe, Denmark launched its “coronapas” system in March to be used domestically [9
The goal of vaccine passports is to pave the way for economic recovery and restore people’s freedoms [10
]. However, these passports also raise concerns about potential violations of people’s autonomy and freedom of choice [7
]. For example, in the UK, more than 375,000 people signed a petition against the rollout of COVID-19 vaccine passports because they “could be used to restrict the rights of people who have refused a COVID-19 vaccine” (https://petition.parliament.uk/petitions/569957
, accessed on 8 August 2021). Even putting aside these ethical issues, it remains unclear how these passports might affect people’s vaccination decisions and well-being. On the one hand, vaccine passports could incentivize people to get vaccinated so they are able to move freely in society [11
]. However, on the other hand, there are reasons to think that measures such as vaccine passports might actually increase some people’s resistance to vaccination or alter the motivation behind their decision to get vaccinated in ways that might have detrimental long-term consequences.
Decades of research shows that societies and individuals can only flourish in environments that foster basic psychological needs [13
]. According to self-determination theory (SDT), there are three of these needs: a need for autonomy (a sense of meaning, volition, choice over one’s life), a need for competence (the feeling of being capable of achieving one’s goals and overcoming challenges), and a need for relatedness (feeling cared for by others, trusted and understood). Satisfaction of these three psychological needs is critical for self-regulating and sustaining behaviours that improve health and well-being, such as exercising, smoking cessation and adherence to prescribed medications [14
]. Recent evidence also suggests that the satisfaction of these needs is important for adherence to preventative COVID-19 measures [16
]. In contrast, the frustration of these needs may elicit ill-being, a lack of motivation to act, or in some cases might even provoke defensiveness (doing the opposite of what is requested) [18
]. People with frustrated needs are also more drawn to conspiracy theories, which could feed into vaccine hesitancy [20
Together, these data provide reasons to expect that people’s willingness and motivation to get vaccinated will depend on their psychological needs—more specifically, the extent to which they feel a sense of autonomy over the decision to get vaccinated, the extent to which they feel competent in their ability to get vaccinated, and the extent to which they feel a sense of relatedness to local and health authorities. If this hypothesis is correct, then if vaccine passports frustrate people’s psychological needs—for example by making people feel a lack of autonomy over their decision—then these passports might paradoxically reduce people’s willingness to get vaccinated.
Furthermore, behaviours are more likely to be sustained over time if people’s motivation for engaging in those behaviours is self-determined and autonomous (performed for internal reasons) than if their motivation is controlled (performed due to external pressures) [18
]. In addition, there is evidence that the frustration of psychological needs can shift people’s motivation from autonomous to controlled [23
A common form of autonomous motivation is identified regulation
—when one identifies and understands the value and importance of a behaviour. This is facilitated when local authorities provide meaningful rationales for a behaviour, and do not apply pressure and external controls [14
]. In contrast, common forms of controlled motivation are external regulation
, in which one only acts to avoid punishment, receive a reward or be in accordance with social pressure and introjected regulation
, in which one acts to receive approval or avoid feelings of guilt [14
]. According to SDT, in contrast to autonomous motivation, these forms of controlled regulations are not sustainable and may improve adherence only for a short period of time [25
]. In the context of vaccination, measures such as vaccine passports may increase vaccination uptake in the short term, but might also shift people’s motivation to external or introjected, making them less likely to sign-up for a second dose of the vaccine, less willing to take up the opportunity to receive a “booster” shot, or less willing to take a yearly vaccine against new variants.
Given these potential detrimental effects of vaccine passports, the aim of this study was to investigate whether people’s willingness and motivation to get vaccinated depends on their psychological needs, and how vaccine passports might affect these needs. Recent studies have called to evaluate the unintended secondary negative effects of vaccine passports, in addition to their effectiveness and impact [7
]. This is the first study to our knowledge to investigate the unintended consequences of domestic vaccine passports using self-determination theory. The results have implications for policy decisions regarding vaccine passports and will help in understanding the importance of autonomy, competence and relatedness in people’s vaccination decisions. We collected data from two countries, one that has implemented vaccine passports and one that has not—Israel and the UK, respectively. We asked participants to report the extent to which their psychological needs were satisfied and frustrated in relation to getting vaccinated. Then, we asked them to report whether they were vaccinated, how willing they would be to get vaccinated and what their attitudes were towards vaccine passports.
Across two countries and 1358 participants, we investigated the relationship between psychological needs and people’s motivation and willingness to take the COVID-19 vaccine. In both the UK and Israel, we found that need frustration—particularly autonomy frustration—predicted unwillingness to get vaccinated and a shift from self-determined to external motivation. Need satisfaction—particularly autonomy and relatedness satisfaction—predicted people’s willingness to get vaccinated. In Israel, autonomy frustration was markedly higher than in the UK, suggesting that people in Israel felt more pressure to get vaccinated.
There could be several reasons as to why people in Israel are more need-frustrated than people in the UK. Differences in health communication messages, social pressure and other circumstantial, social, and cultural differences between the two countries could all contribute. However, the vaccine passports in Israel, called “green passes”, received considerable backlash and criticism, including several appeals to the Israeli supreme court, with citizens and healthcare experts seeing them as coercion and against individual autonomy and freedom of choice [32
]. It seems reasonable to expect, therefore, that vaccine passports would frustrate psychological needs—particularly people’s sense of autonomy—and our data are consistent with this hypothesis. Moreover, we found that the more people felt autonomy frustrated, the more they were against vaccine passports.
To the extent that vaccine passports do increase psychological need frustration, our data suggest that they might reduce people’s willingness to get vaccinated. A vast body of research showed that the satisfaction of the three psychological needs (autonomy, competence and relatedness) is critical for internalising and maintaining behaviours that improve health and well-being [14
]. Moreover, frustration of these needs may elicit undesired responses, including disengagement from the activity or doing the opposite of what is requested (oppositional defiance) [19
]. Our study extends these findings to vaccination behaviour, showing that people’s willingness to get vaccinated against COVID-19 is related to the satisfaction and frustration of psychological needs around getting vaccinated—particularly their sense of autonomy. For this reason, control measures such as vaccine passports that frustrate psychological needs may have detrimental effects on people’s motivation and willingness to get vaccinated.
Furthermore, if people with frustrated needs do succumb to the pressure to get vaccinated, they are more likely to do so due to external motivation (feeling pressure from others or to satisfy others) rather than due to autonomous identified motivation (wanting to take responsibility over one’s health and understanding the importance of the decision). Although such a possibility would provide some immediate benefits in the form of vaccination rates, it might also produce unintended side effects. For example, as previously mentioned, people might be less willing to receive a “booster” shot or to take a yearly vaccine against new variants. In contrast, if people are autonomously motivated to get vaccinated, sustained adherence to vaccine guidance will be more likely [13
Autonomy-frustrating policies such as vaccine passports may also have long-term public health implications in terms of trust in the health system. People who are amotivated, or who feel pressured are unlikely to build good and trusting relationships with local governments and health authorities—relationships that are crucial for public health adherence and behaviour change to occur [16
]. Moreover, need frustration can damage people’s well-being, so need-frustrating policies might add to the already heavy burden of the pandemic on people’s mental health [19
]. It is therefore important for governments and policy makers to apply health and risk communication that enhances basic psychological needs, such as creating an autonomy-supportive health care climate and building a caring and trusting relationship with the public (see [16
] for full guidelines).
Strengths and Limitations
It is important to note that, in Israel, domestic vaccine passports are given only to fully vaccinated residents or people who have recovered from COVID-19; this may be more restricted than other passports’ initiatives, such as the “coronapas” in Denmark, where the requirements for a valid coronavirus passport are full vaccination or two weeks since first dose; a negative test taken within the last 72 h; or recent recovery from COVID-19 [9
]. This may influence the level of perceived autonomy, and hence the motivation and decision to get vaccinated. In this study, we evaluated attitudes towards domestic vaccine passports for everyday use (e.g., going to restaurants, social events), not for facilitating international travel, which may have different implications and should be examined.
In addition, this study only analysed data from two developed and democratic countries. Although previous research has shown that the satisfaction of basic needs for autonomy, relatedness and competence are essential for optimal functioning across cultures and across individual differences in need strength [28
], it is still important to investigate whether our findings are applicable to other countries and cultures.
Furthermore, our study is quantitative in nature, also eliciting qualitative data about attitudes towards vaccine passports, could enhance our understanding of the reasons behind the satisfaction and frustration of needs.
One key strength of this study is that it includes large, representative samples from two different countries (the UK and Israel). Because these countries have advanced vaccination programmes, we were able to investigate the relationships between psychological needs and actual vaccination behaviour in addition to vaccination intentions. A key limitation of this study is the observational design. Although we demonstrated robust relationships between psychological needs and people’s willingness to get vaccinated, we cannot establish causal links between the two. Although it is possible need frustration reduces willingness to get vaccinated, it is also possible that people first decide whether to get vaccinated, and that decision ultimately leads to more or less need frustration. Such a pattern would still be of interest, however. For example, authorities in the US are going to great lengths to encourage people who have chosen not to get vaccinated to change their minds. If people are experiencing need frustration (for example, because of vaccine passports), it is likely to be even more difficult to change their minds [17