National identity predicts public health support during a global pandemic

The ongoing COVID-19 pandemic is a devastating global health crisis. Without a vaccine or effective medication, the best hope for mitigating virus transmission is collective behavior change and support for public health interventions (e.g., physical distancing, physical hygiene, and endorsement of health policies). In a large-scale international collaboration (N = 46,650 across 67 countries), we investigated why people adopted public health behaviors and endorsed public policy interventions (e.g., closing bars and restaurants) during the early stages of the pandemic (April-May, 2020). Results revealed that respondents who identied more strongly with their nation consistently reported engagement in public health behaviors and greater support for public health policies. We also found a small effect of political orientation, indicating that left-wing respondents were more likely to report public health behaviors and support for public health measures than right-wing respondents. We discuss the implications of links between national identity, leadership, and public health for managing the COVID-19 and future pandemics.

the nation than for the well-being of fellow citizens (Cichocka, 2016;Cislak et al., 2018;Marchlewska et al., 2020). Thus, national narcissists may be less inclined to engage in behaviours to prevent the spread of COVID-19 (Nowak et al., 2020). Therefore, in predicting compliance with public health measures, we distinguished the effects of national identi cation from those of national narcissism.

Overview
The COVID-19 pandemic is a truly global crisis with over 200 countries reporting infections. To understand how public health support and their predictors vary around the globe, we launched a collaborative, international project in April 2020 collecting large-scale data from as many nations as possible. We collected quote samples that were representative with respect to gender and age in 67 countries (n = 46,650; see Fig. 1). We analysed the data using multi-level models, which allows us to account for country-level variation in economic, political and health measures while examining whether national identi cation predicted public health support. We modeled country-level factors, like the Human Development Index (HDI), to see if the impact of person-level factors, like national identi cation, would predict public health support, even after adjusting for the general health and standard of living in a country (see Methods for details and sample items). We also adjusted for the COVID-19 infection and mortality rates within each country to ensure that public health support was not merely a function of local risks.
Our results provide robust evidence that national identi cation is a reliable predictor of all three forms of public health support measured in our survey: self-reported spatial distancing, physical hygiene, and policy support. Citizens who identi ed more strongly with their nation reported greater support for critical public health measures, even after adjusting for national narcissism and political ideology (as well as the country-level Human Development Index and local rates of COVID-19 infections and mortality). Right-wing participants reported lower levels of support for all three protective measures than more left-wing participants. National narcissism was only weakly related to support for several of the measures. In sum, the results provide clear evidence that national identi cation is related to public health support across national and cultural contexts, and may be useful for promoting collective health responses to the COVID-19 pandemic.
People generally reported following the guidelines for contact and hygiene and they supported policies that were intended to reduce the impact of COVID-19 (i.e., means for all three measures were above 8, on scales ranging from 0 to 10; see Table 1). For all measures, except political ideology, there were negative relationships between HDI scores and country-level means (see Table 2). In other words, citizens in countries with higher scores on the global Human Development Index also reported less support for COVID-19 public health measures. Note: * p < .05; *** p < .001 As can be seen from the coe cients presented in Table 3, national identi cation was the most reliable and strongest predictor of our COVID-19 public health support measures (see Fig. 2 for the coe cients in each country). It was signi cantly and positively related to all three measures (even after adjusting for national narcissism and political ideology). Individuals with stronger national identi cation (relative to other people within their own nation) reported stronger support for limiting physical distance and improving physical hygiene than individuals with weaker identi cation, and they also endorsed COVID-19 public health policies to a greater extent. Note: * p < .05; *** p < .001 National narcissism was signi cantly positively related to two of the three protective measures (albeit weakly). Individuals scoring higher in national narcissism supported recommendations for physical hygiene and endorsed COVID-19 related policies more strongly compared to individuals with lower levels of national narcissism.
The relations between political ideology and public health support were negative (albeit weakly) for all three outcome measures, indicating that individuals with more left-leaning or liberal political orientation tended to adhere to recommendations for contact, hygiene and supported COVID-19-related policies more strongly than those with more right-leaning or conservative political orientation. The three predictors accounted for 8% of the person-level variance of the contact measure, for 7% of the person-level variance of the hygiene measure, and 5% of the person-level variance of the policy support measure.

Discussion
Our research suggests that national identities can play a constructive role in the ght against a global pandemic. Indeed, following WW2, early work in social psychology had a tendency to focus on the negative side of nationalism and leadership persuasion, such as deconstructive obedience to authority (Milgram, 1963) and group conformity to incorrect beliefs held by others (Asch, 1956). However, in the decades since then, research on social identity (Tajfel, 1978) and a "social cure" approach to mental health (Jetten, Haslam & Haslam, 2011) have presented a more balanced view, suggesting that there is also a pro-social side to social identity. It was based on this latter perspective we predicted, and found, that national identi cation would be positively associated with public health support around the globe.
Individual differences in the strength of identi cation with one's nation robustly predicted public health support, operationalized as behavioral health intentions (physical distance and physical hygiene) and support for COVID-19 policy interventions. In short, citizens who identi ed more strongly with their nation reported greater engagement with critical public health measures around the globe. These results are consistent with the social psychological literature on the bene ts of identifying with one's social groups, in this case, one's nation. It also underscores a potential bene t of national identi cation. Our research provides evidence that this form of identi cation might be relevant to understanding public health behavior and delivering effective campaigns to promote those behaviours during a global pandemic.
There is reason to believe that different forms of social identi cation can undercut public health. For instance, recent research suggests that partisanship within countries (i.e., when people strongly identify with a speci c political party) may be associated with risky behavior. One recent paper found that partisanship was a robust predictor of spatial distancing behavior (Gollwitzer, Martel, Brady, Knowles, & Van Bavel, 2020; see also Alcott et al., 2020). Using geotracking data of 15 million smartphones per day, they found that counties that voted for Donald Trump (a Republican) over Hillary Clinton (a Democrat) in 2016 exhibited 14% less physical distancing during the early stages of the pandemic. Moreover, these partisan differences in distancing predicted subsequent increases in infections and morality in counties that voted for Donald Trump. This may be due to leadership, social norms, and media consumed by people from different identity groups. As such, social identi cation is not always conducive to healthy behavior.
National identi cation and narcissism were both positively associated with more right-wing political ideology, yet, their associations with COVID-19 protection were very different. Right-wing political beliefs were associated with less compliance with COVID-19 protection, compared to left-wing political beliefs. This relationship between political beliefs and compliance has been observed in several countries (e.g., Gollwitzer et al., 2020; Ponce, 2020). However, both national identi cation and national narcissism were associated with greater support for public health measures, whereas right-wing political ideology was associated with less support for public health measures. This suggests that in a pandemic, a collective identity might lead people to value the protection of the entire group even after adjusting for their ideological differences. This can be seen as the positive side of national identity and how it might be leveraged in a global crisis to promote activities that bene t a society.
It is also important to note that the relation between national identity and public health support was distinct from national narcissism and political ideology. In past research, national narcissism has predominantly been linked to problematic attitudes both towards other and own group members (Cichocka, 2016;Cichocka & Cislak, 2020;Marchlewska et al., 2020). However, we found national narcissism to be positively associated with self-reported physical hygiene and support for COVID-19 preventative policies. Still, these effects were much smaller than those for national identi cation and depended on the context (i.e., this relation was associated with lower likelihood of physical distancing in relatively more developed countries). This suggests that future work should carefully consider national differences in human development as well as local norms associated with national identity. It is also noteworthy that there was an unexpected negative link between HDI and health behaviors. It is unclear why this link exists but we speculate that people in these countries might have placed a greater faith in their political and medical institutions during the early stages of the pandemic.

Implications
Our evidence suggests that national identity may have modest predictive value for people's endorsement of and adherence to public health measures in the context of COVID-19. This information may be leveraged to create a sense of inclusive nation-based in-groups, potentially increasing engagement with recommended policies. Political and public health leaders might be able to similarly adapt effective communication strategies to appeal to a sense of national identi cation. Indeed, this might be particularly helpful (albeit di cult) in highly polarized countries where adherence to public health recommendations has become a partisan issue (see Gollwtizer et al., 2020). Such recategorizations to overarching inclusive groups (see, for example, Gaertner et al., 2016) may be necessary to prevent unhealthy behaviours. As such, leaders who wish to inspire public health behavior might bene t from connecting the issue to feelings of national identity. However, we note that national identi cation also be used to foment intergroup con ict and the effective application of these appeals requires future research.
Our study focused on COVID-19 protection within each country, but effective management of the pandemic requires collaboration across nations (Dovidio et al., 2020;Harari, 2020). Although one might worry that national identi cation might be associated with greater preoccupation with one's own country's response, it could translate into concern for other nations as well. In past research, national identi cation (in its nonnarcissistic form) was associated with more positive attitudes towards other nations (Golec de Zavala, Cichocka, & Bilewicz, 2013). National narcissism, in contrast, is likely to be associated with lower solidarity with other nations in the crisis (e.g., Gorska et al., 2019). Thus, the nature of national identity (e.g., as being helpful vs. militarily aggressive) might be an important determinant of the effectiveness of identity and the potential for international cooperation.

Limits On Generalizability
The vast majority of published research in psychology and social sciences has been conducted in so-called WEIRD cultures (Henrich, Heine, & Norenzayan, 2010), typically restricted to the narrow western and educational setting of American or European university students, and nonrepresentative online participants from industrialized, rich and democratic countries. The COVID-19 pandemic, however, is a truly global issue, currently affecting 213 countries and territories all over the world. We aimed to collect representative samples to help make generalizations to the wider population within each country as well as the broader sample of countries around the globe. Although we managed to collect data from 67 countries and territories, we were nevertheless unable to ensure representative samples from many countries or even conduct our survey in other countries (especially in many African countries as well as the Middle East). Therefore, we need to focus our generalizations on nations where we managed to complete this research and the speci c samples we obtained.
A major limitation of our work is the fact that it was correlational in nature and that it was conducted during the early phase of the pandemic.
Thus, while we expect that national identi cation is more likely to cause public health behavior than the other way around, we have no evidence as to the directionality of this effect or whether it would apply during later stages of the current or future pandemics. Indeed, it is possible that national identity increases during times of crisis as people recognize their duty as citizens to help respond to this issue or that a third variable such as international competition explains this correlation (e.g., Bieber, 2020). We encourage future work to examine ways to experimentally manipulate national identi cation or tighten the link between identi cation and the public health measures required to mitigate the spread of the pandemic. A related issue is the critical need to measure actual behavior rather than behavioral intentions or policy support (see Isler, Isler, Kopsacheilis, & Ferguson, 2020) as well as consider access to the necessary resources to engage in health behavior.

Conclusion
The COVID-19 pandemic sweeping through the world is one of the most devastating global health crises of the century. In the absence of a successfully-tested vaccine or effective medicine, efforts to inspire collective action for greater compliance with public health measures (e.g., spatial distancing, physical hygiene and support for health policies) become the central challenge when mitigating the transmission of the SARS-CoV-2 virus. Our large-scale international collaboration across 67 countries suggests that identi cation with one's nation is associated with support for critical public health measures. This nding might provide an important insight for leaders and policy makers when designing programs and messages to promote critical public health initiatives.

Methods And Analysis
In April 2020, we launched a call using social media to collect data all over the world on psychological factors that might be related to COVID-19 pandemic response, with public health support as the primary outcome. Each team was asked to collect data from at least 500 participants, representative with respect to gender and age, in their own country or territory. We created a survey in English (see below) that we sent to each team. The survey was approved by the ethics board at the University of Kent. Where necessary, each team translated the survey into the local language, using the standard forward-backward translation method, and then collected the data. The datasets were then collated and analyzed using multi-level models. We report how we determined our sample size, all data exclusions (if any), all manipulations, and all measures in the study (see supplement).