Introduction: Adherence to COVID-19 mitigation measures is an important vehicle that has contributed to the fight against the pandemic. The present study investigated potential changes of the level of adherence and its predictors between 2020 and 2021 in eight countries. Methods: Adherence to COVID-19 measures and its potential predictors (perception of usefulness of the measures, rating of the governmental COVID-19 communication, mental health variables, COVID-19 burden) were compared between representative population samples from European Union countries (France, Germany, Poland, Spain, Sweden) and non-European Union countries (Russia, UK, USA) assessed in 2020 (N = 7,658) and 2021 (N = 8,244). Results: In the overall sample, multiple analyses of variance revealed significantly higher levels of adherence to the measures, their perception as useful, positive mental health, and feelings of being well supported and well informed by governments in 2020 than in 2021. In contrast, feelings of being left alone and symptoms of depression, anxiety, and stress were significantly higher in 2021 than in 2020. In France, Poland, Spain, and the UK, the adherence level was significantly higher in 2020 than in 2021. In European Union countries, ratings of governmental communication were less positive, and levels of mental health were lower in 2021 than in 2020. In non-European countries, an opposite result pattern was found. Conclusion: The current results indicate a decrease in adherence to the mitigation measures and factors that could foster it. Potential ways how governments and authorities could enhance the population’s trust in COVID-19 mitigation measures are discussed.

To fight the spread of COVID-19, many governments introduced lockdowns, curfews, and behavioral mitigation measures such as “social distancing,” hand disinfection, and wearing of face masks in public places (for detailed explanation, see [1]). In some countries, vaccination against the virus has become compulsory. Only vaccinated or recovered people were allowed to enter public places. In other countries, a negative COVID-19 test was sufficient to participate in public life [2]. The introduced measures differed between countries and within the same country at different points in time [3]. The adherence to the measures in the population is important to reduce the COVID-19 cases, the severity of the infection course, and the COVID-19 mortality rate [4‒6].

Following recent cross-national research, the level of adherence to the measures is positively linked to the perception of the measures as useful [7, 8]. The usefulness perception and the adherence to the governmental measures are positively associated with the perception of the governmental communication on the pandemic as clear and understandable, credible and honest, as well as guided by the interests of people [7, 9]. Persons who felt themselves supported, well informed, and taken seriously by government and authorities in the COVID-19 situation were characterized by high usefulness perception and adherence to the measures [10, 11]. In contrast, individuals who felt left alone tended to perceive the measures as less useful and to have a low level of adherence [7, 12].

Furthermore, usefulness perception and adherence to the measures are closely related to one’s mental health [13, 14]. Following dual-factor models [15], mental health is not only the absence of psychopathology. It consists of two interrelated but distinct dimensions: positive and negative. To assess the complete level of mental health, both dimensions should be considered [16]. Since the pandemic outbreak, available studies reported an increase in symptoms of depression, anxiety, and stress that represent the negative dimension of mental health [17, 18]. In contrast, positive mental health (PMH) – the psychological, emotional, and social well-being [19] – that represents the positive dimension decreased [20]. Both dimensions of mental health are directly related to usefulness perception and adherence to COVID-19 mitigation measures [7]. While they are negatively associated with depression, anxiety, and stress symptoms, their relationship with PMH is positive [13]. Furthermore, available literature described an indirect link between the mental health factors, on the one hand, and the usefulness perception and adherence to the COVID-19 mitigation measures, on the other hand. Psychological burden caused by the COVID-19 situation mediated this relationship. Specifically, the lack of perceived governmental support and the unpredictability of the duration of the COVID-19 situation can result in a high level of psychological burden that is characterized by frustration and hopelessness [21]. Cross-sectional and longitudinal research showed that especially people with enhanced symptoms of depression, anxiety, and stress were at risk for a high level of psychological burden by the COVID-19 situation. In contrast, the level of PMH predicted the burden negatively [22, 23]. Psychological burden by the COVID-19 situation served as a significant negative predictor of usefulness perception and adherence to the mitigation measures [24, 25].

The governmental measures to fight the pandemic spread changed over time, which could also change the level of adherence to the measures among the population [12]. It could be that some people evaluated the COVID-19 situation as less harmful during its early stages. Therefore, they could show lower adherence to the introduced measures. With the progress of the pandemic and the rising rates of infection and mortality, they could recognize the seriousness of the situation and tend to a higher adherence. In contrast, we cannot exclude that the trust of others – who showed high adherence at the pandemic outbreak – in the effectivity of governmental measures decreased over time. As a consequence, their perception of usefulness of the measures and the adherence to them could also decrease.

To better understand the consequences of the COVID-19 situation and to be able to predict their further course, we compared exploratory the level of the usefulness perception of COVID-19 mitigation measures and of the adherence to them, as well as their previous predictors (perception of the governmental communication as clear and understandable, credible and honest, guided by the interests of the people; feeling of being well supported, informed, taken seriously and left alone by the government; PMH, symptoms of depression, anxiety, and stress, and COVID-19 burden) [13] between the years 2020 and 2021. We used two population-representative datasets from eight countries with different welfare systems (for detailed explanation, see [26, 27]) that were assessed in May/June 2020 and 2021 [7, 28]. The datasets included five countries that belong to the European Union: France (FR), Germany (GE), Poland (PL), Spain (ES), and Sweden (SV); and three non-European Union countries: Russia (RU), the UK (UK), and the USA (US).

In all eight countries, the first COVID-19 cases were detected in January 2020 [29]. In France, Germany, Poland, Spain, Russia, the UK, and the USA, the first national lockdown was introduced in March 2020 that included a “stay-at home” order, closing of public establishments, bands on traveling, compulsory wearing of face masks, and social distancing. In Sweden, the government did not introduce strict compulsory lockdowns except bans on large public gatherings and events. During the first data collection in May/June 2020, about one million COVID-19 cases were detected worldwide [30]. Considering the eight investigated countries, most cases were detected in the USA followed by Spain; the fewest cases were detected in Poland (e.g., [31, 32]). At that time, an easing of the lockdown such as re-opening of some public establishments and allowing of larger public gatherings began in the investigated countries [30]. The wearing of face masks remained compulsory in public places in France, Germany, Poland, Spain, and Russia; in the USA, the wearing was compulsory at all places outside the home; in the UK, the wearing was only recommended; and in Sweden, there were no specific recommendations on the wearing of face masks [33]. The willingness for anti-COVID-19 vaccination as soon as it will be available was relatively high in most of the eight countries in May/June 2020; a cross-national study revealed the highest vaccination willingness of 75.4% in the USA, and the lowest willingness was in Russia with 54.9% [8]. The willingness of the other six countries was within this range [8]. Between the data collections in 2020 and 2021, there were several increases and decreases of active COVID-19 cases in the investigated countries that were accompanied by new lockdowns and their easing [2, 5]. The main raising of the case numbers was recorded in winter 2020/2021 in all eight countries. During the second data collection in May 2021, there was a slow decline of active COVID-19 cases in the eight countries [29]. Worldwide, there were about 4.2 million detected COVID-19 cases [30]. Of the eight investigated countries, the most cases were again detected in the USA, followed by France; the fewest cases were detected in Poland [30]. Considering the mitigation measures, there were still bans on public events in the investigated countries, in May 2021; the only exception was the USA, with a recommendation for the cancellation of public events [33]. In France, Germany, and Spain, there was a “stay-at-home” requirement except for essentials; in Poland, the UK, and the USA, the “stay-at-home” was recommended; and in Russia, this mitigation measure was no longer valid. The wearing of face masks in public places was compulsory in the eight countries; moreover, the wearing was mandatory at all places outside the home in France and Spain [33]. In the eight countries, anti-COVID-19 vaccinations were available and for some occupation sectors such as the medical care sector being vaccinated became mandatory in May 2021 [34, 35]. Moreover, in the seven countries with mitigation measures, a significant easing of the measures was introduced for already vaccinated people. Non-vaccinated people required a negative COVID-19 test no older than 24 h or 48 h to enter public establishments [2]. This was a relief for people with a high vaccination willingness, while this regulation put under pressure persons with a low vaccination willingness [36]. In May 2021, considering the eight investigated countries, the highest vaccination willingness was in the UK and the lowest in Russia [28].

The continuation of the COVID-19 pandemic, the fluctuation in active case numbers, and the permanent changes in validity of mitigation measures, including lockdowns, could influence the usefulness perception of the governmental measures and the adherence to them among the population. Against this background, we aimed to investigate whether potential changes of usefulness perception, adherence, and their predictors show a universal course across different countries or whether they exhibit country-specific patterns. Of note, there was no strict, consistent pattern of the introduced mitigation measures, following that we could clearly sort the eight countries. Therefore, to avoid speculations, we did not formulate specific hypotheses regarding the potential changes, and the present investigation had an explorative character.

Procedure and Participants

The present study is a secondary data analysis of previous research that focused on predictors of adherence to COVID-19 mitigation measures [7, 28]. The first data collection took place from the end of May to the beginning of June 2020. The sample 2020 consisted of 7,658 participants from eight countries: FR: N = 940, GE: N = 917, PL: N = 924, RU: N = 986, ES: N = 960, SV: N = 922, UK: N = 1,105, and US: N = 904. The second data collection took place in the middle of May 2021. The sample 2021 included 8,244 participants: FR: N = 1,001, GE: N = 1,145, PL: N = 1,004, RU: N = 1,024, ES: N = 985, SV: N = 1,003, UK: N = 1,050, and US: N = 1,032. The two data collections were independent from each other. Table 1 shows the demographics of both samples.

Table 1.

Country-specific demographic variables in sample 2020 and 2021

YearAllFRGEPLRUESSVUKUS
Gender (female), % 2020 53.0 57.7 51.0 54.7 54.7 51.0 51.0 52.2 51.8 
2021 52.8 54.9 52.0 53.7 51.5 51.9 51.5 55.4 51.3 
Age groups, % 
 18–24 years 2020 8.1 8.5 6.7 9.6 7.8 6.3 6.8 10.0 8.7 
2021 7.4 8.8 7.7 9.7 8.5 7.5 6.0 2.7 8.4 
 25–34 years 2020 16.6 14.8 12.8 17.5 20.9 14.0 20.9 17.9 13.5 
2021 16.2 14.8 14.2 18.1 22.0 14.1 19.6 13.4 13.5 
 35–44 years 2020 16.5 14.9 14.4 18.9 20.3 21.3 8.8 16.9 15.6 
2021 16.8 16.3 14.5 19.7 21.6 19.7 12.7 15.0 15.0 
 45–54 years 2020 18.4 18.5 19.8 15.4 17.3 20.9 19.0 18.0 18.6 
2021 17.8 17.4 19.8 15.6 18.2 20.4 17.1 15.7 18.2 
 55 years and older 2020 40.4 43.3 46.3 38.5 33.7 37.6 44.5 37.1 43.6 
2021 41.8 42.8 43.8 36.9 29.8 38.3 44.6 53.2 44.9 
Marital status (with partner), % 2020 64.2 66.4 60.7 67.7 69.0 67.0 58.2 61.7 63.2 
2021 62.4 62.3 57.6 64.5 70.0 64.1 55.3 64.5 61.3 
Social status, % 
 Lower class 2020 5.1 7.6 7.6 3.8 2.8 4.1 5.1 2.7 7.6 
2021 5.8 7.7 6.9 4.8 4.4 4.1 6.9 3.0 8.7 
 Working class 2020 22.2 19.3 18.4 15.8 19.1 31.4 20.7 33.8 16.4 
2021 22.5 20.6 18.9 17.7 17.5 33.9 21.8 32.6 17.4 
 Lower middle class 2020 25.9 26.7 25.3 32.6 37.3 21 13.6 30.2 19.1 
2021 26.3 31.0 28.7 34.0 36.1 20.1 14.8 26.8 18.8 
 Middle middle class 2020 36.8 32.8 38.9 36.3 36.8 36.9 46.6 28.4 39.6 
2021 35.5 30.9 36.9 32.5 35.4 36.8 42.9 32.7 35.9 
 Upper middle class 2020 12 9.2 8.9 3.4 6.6 12.8 4.9 15.9 
2021 8.6 8.7 7.7 8.5 5.0 5.1 12.8 4.6 16.2 
 Upper class 2020 1.7 0.5 2.7 0.5 0.1 1.2 1.3 
2021 1.3 1.2 1.0 2.6 1.6 0.1 0.8 0.4 2.9 
Urbanicity (large city), % 2020 42.3 28.9 35.1 48.8 77.3 37.9 47.7 25.5 38.4 
2021 40.6 29.9 35.2 43.8 74.7 38.6 45.4 22.3 35.9 
YearAllFRGEPLRUESSVUKUS
Gender (female), % 2020 53.0 57.7 51.0 54.7 54.7 51.0 51.0 52.2 51.8 
2021 52.8 54.9 52.0 53.7 51.5 51.9 51.5 55.4 51.3 
Age groups, % 
 18–24 years 2020 8.1 8.5 6.7 9.6 7.8 6.3 6.8 10.0 8.7 
2021 7.4 8.8 7.7 9.7 8.5 7.5 6.0 2.7 8.4 
 25–34 years 2020 16.6 14.8 12.8 17.5 20.9 14.0 20.9 17.9 13.5 
2021 16.2 14.8 14.2 18.1 22.0 14.1 19.6 13.4 13.5 
 35–44 years 2020 16.5 14.9 14.4 18.9 20.3 21.3 8.8 16.9 15.6 
2021 16.8 16.3 14.5 19.7 21.6 19.7 12.7 15.0 15.0 
 45–54 years 2020 18.4 18.5 19.8 15.4 17.3 20.9 19.0 18.0 18.6 
2021 17.8 17.4 19.8 15.6 18.2 20.4 17.1 15.7 18.2 
 55 years and older 2020 40.4 43.3 46.3 38.5 33.7 37.6 44.5 37.1 43.6 
2021 41.8 42.8 43.8 36.9 29.8 38.3 44.6 53.2 44.9 
Marital status (with partner), % 2020 64.2 66.4 60.7 67.7 69.0 67.0 58.2 61.7 63.2 
2021 62.4 62.3 57.6 64.5 70.0 64.1 55.3 64.5 61.3 
Social status, % 
 Lower class 2020 5.1 7.6 7.6 3.8 2.8 4.1 5.1 2.7 7.6 
2021 5.8 7.7 6.9 4.8 4.4 4.1 6.9 3.0 8.7 
 Working class 2020 22.2 19.3 18.4 15.8 19.1 31.4 20.7 33.8 16.4 
2021 22.5 20.6 18.9 17.7 17.5 33.9 21.8 32.6 17.4 
 Lower middle class 2020 25.9 26.7 25.3 32.6 37.3 21 13.6 30.2 19.1 
2021 26.3 31.0 28.7 34.0 36.1 20.1 14.8 26.8 18.8 
 Middle middle class 2020 36.8 32.8 38.9 36.3 36.8 36.9 46.6 28.4 39.6 
2021 35.5 30.9 36.9 32.5 35.4 36.8 42.9 32.7 35.9 
 Upper middle class 2020 12 9.2 8.9 3.4 6.6 12.8 4.9 15.9 
2021 8.6 8.7 7.7 8.5 5.0 5.1 12.8 4.6 16.2 
 Upper class 2020 1.7 0.5 2.7 0.5 0.1 1.2 1.3 
2021 1.3 1.2 1.0 2.6 1.6 0.1 0.8 0.4 2.9 
Urbanicity (large city), % 2020 42.3 28.9 35.1 48.8 77.3 37.9 47.7 25.5 38.4 
2021 40.6 29.9 35.2 43.8 74.7 38.6 45.4 22.3 35.9 

2020: all: N = 7,658; France (FR): N = 940, Germany (GE): N = 917, Poland (PL): N = 924, Russia (RU): N = 986, Spain (ES): N = 960, Sweden (SV): N = 922, the UK (UK): N = 1,105, the USA (US): N = 904; 2021: All: N = 8,244; FR: N = 1,001, GE: N = 1,145, PL: N = 1,004, RU: N = 1,024, ES: N = 985, SV: N = 1,003, UK: N = 1,050, US: N = 1,032; due to rounding, the sum of the frequencies is not always 100%.

In 2020 and 2021, the independent social marketing and research institute YouGov (www.yougov.de) collected the data via population-based online panel surveys in the national language of the countries. Participants were recruited from residential populations (age: 18 years and above). YouGov worked with quota samples and implemented gender, age, and region stratification to achieve representativeness for the population of each of the eight countries.

Participants were compensated by panel-specific tokens that can be converted in monetary payment or voucher. The Ethics Committee of the Faculty of Psychology of the Ruhr-Universität Bochum approved the implementation of the present study (approval number: 118 and 118 extended). YouGov obtained the required permits and approvals for the data collection in all included countries. Both data collections were pre-registered with AsPredicted.org (1. May 25, 2020: pre-registration number: #41686; 2. May 05, 2021: pre-registration number: #64865). All procedures performed in this study were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards. All participants were properly instructed and gave online their informed consent to participate by clicking a box. This procedure has been explicitly approved by the responsible ethics committee. All national regulations and laws regarding human subject research were followed.

Measures

Demographics

Following recommendations from available research (e.g. [37‒40]), the participants were asked to indicate their gender (0 = woman, 1 = man), age range (1 = 18–24 years, 5 = 55 years and older), marital status (0 = without partner, 1 = with partner), social status (1 = lower class, 6 = upper class), and urbanicity (0 = small city or rural community, 1 = large city) (see Table 1 for details).

COVID-19 Specific Content

Participants rated (1) to what extent they think the COVID-19 mitigation measures are useful and (2) how much they adhere to the introduced measures, respectively, on a 5-point Likert-type scale (0 = not at all, 4 = very strong). Moreover, they rated (3) to what extent they assess the COVID-19 communication of the national government and authorities as (3a) clear and understandable, (3b) credible and honest, (3c) guided by interests of the people, respectively, on 5-point Likert-type scales (0 = not at all true, 4 = very true). Also, they rated (4) to what extent they feel themselves by the national government and authorities (4a) well supported, (4b) well informed, (4c) taken seriously, and (4d) left alone, respectively, on 5-point Likert-type scales (0 = not at all true, 4 = very true).

Positive Mental Health

The level of PMH was measured with the unidimensional Positive Mental Health Scale (PMH-Scale [19]) that is an internationally well-established instrument for the assessment of psychological, emotional, and social well-being. Previous research showed good results for measurement invariance of the PMH-Scale across the eight countries focused in the present study [41]. The nine items are rated on a 4-point Likert-type scale (e.g., “I enjoy my life”; 0 = do not agree, 3 = agree). The higher the sum score, the higher the PMH level. In the current study, internal consistency scores ranged from: sample 2020: α = 0.873, 95% CI [0.861, 0.885] (FR) to 0.933, 95% CI [0.926, 0.939] (SV); sample 2021: α= 0.896, 95% CI [0.886, 0.905] (FR) to 0.937, 95% CI [0.931, 0.942] (SV).

Depression, Anxiety, and Stress Symptoms

The Depression Anxiety Stress Scales 21 (DASS-21 [42]) measured symptoms of depression, anxiety, and stress with, respectively, seven items per subscale (e.g., depression subscale: “I felt that life was meaningless”; anxiety subscale: “I felt scared without any good reason”; stress subscale: “I found it hard to wind down”). The measurement invariance of the DASS-21 across the eight countries focused in the present study has been previously demonstrated [43‒45]. Items are rated on a 4-point Likert-type scale (0 = did not apply to me at all, 3 = applied to me very much or most of the time). Higher sum scores indicate higher levels of the symptoms. In the current study, internal consistency scores for the subscales ranged from: sample 2020: α= 0.900, 95% CI [0.890, 0.909] (RU) to 0.937, 95% CI [0.931, 0.943] (US) for depression, α= 0.851, 95% CI [0.837, 0.864] (UK) to 0.923, 95% CI [0.915, 0.930] (US) for anxiety, and α= 0.874, 95% CI [0.861, 0.886]  (ES) to 0.920, 95% CI [0.912, 0.927] (RU) for stress; sample 2021: α= 0.902, 95% CI [0.893, 0.911] (RU) to 0.941, 95% CI [0.936, 0.947] (UK) for depression, α= 0.862, 95% CI [0.850, 0.874] (GE) to 0.901, 95% CI [0.892, 0.910] (US) for anxiety, and α= 0.881, 95% CI [0.869, 0.891] (SV) to 0.919, 95% CI [0.912, 0.926] (GE) and 95% CI [0.911, 0.926] (PL) for stress.

Psychological Burden Caused by COVID-19

The COVID-19 Burden Scale [23] assessed the psychological burden caused by the COVID-19 situation. The six items (e.g., “I feel socially isolated”) are rated on a 7-point Likert-type scale (1 = I do not agree, 7 = I totally agree). The higher the sum scores, the higher the burden. In the current study, internal consistency scores ranged from: sample 2020: α = 0.664, 95% CI [0.607, 0.679] (US) to α = 0.762, 95% CI [0.737, 0.785] (GE); sample 2021: α = 0.665, 95% CI [0.632, 0.696] (US) to α = 0.791, 95% CI [0.772, 0.809] (GE).

Earlier validated national language versions of the included instruments were used (DASS-21: [43], e.g., PMH: [46], COVID-19 Burden Scale: [47]). When no validated national language version was available, the international team of the BOOM-Project translated the scales into the national language from the English language version by the customary translation-back-translation-modification procedure [48]. All instruments focused on the past 2 weeks.

Statistical Analyses

Statistical analyses were conducted using the Statistical Package for the Social Sciences (SPSS 28; [49]). After descriptive analyses, we compared the means of the investigated variables between sample 2020 and sample 2021 by calculating multiple analyses of variance (MANOVAs). Considering that Stevens [50] recommends not to include more than ten dependent variables in one MANOVA, we ran two analyses. In the first MANOVA, we included the evaluation of usefulness of COVID-19 mitigation measures, the adherence to them, the perception of the COVID-19 communication as clear and understandable, credible and honest, guided by interests of people, and the feeling of being well supported, well informed, taken seriously, and left alone as dependent variables. In the second MANOVA, we included PMH, symptoms of depression, anxiety, and stress, and COVID-19 burden as dependent variables. The Box’s test was significant in both analyses. Therefore, the Hotelling’s trace statistic was used. Partial eta squared (ηp2) served as the effect-size measure of the main effects. Post hoc comparisons were all Bonferroni-corrected (level of significance: p < 0.05, two-tailed). All calculations were first conducted with the overall samples (2020: N = 7,568; 2021: N = 8,244) and subsequently with the eight country-specific samples, respectively, in order to identify possible country-specific result patterns.

Table 2 shows the descriptive statistics of the investigated variables for the overall samples and for each country-specific sample in 2020 and 2021. Table 3 presents findings of the MANOVAs.

Table 2.

Descriptive statistics of assessed variables (2020 and 2021)

YearM (SD)
allFRGEPLRUESSVUKUS
Usefulness of measures 2020 2.31 (1.16) 2.08 (1.08) 2.60 (1.16) 2.09 (1.13) 2.16 (1.21) 2.48 (1.14) 2.16 (1.20) 2.51 (1.00) 2.36 (1.24) 
2021 2.21 (1.22) 1.79 (1.12) 2.35 (1.26) 1.91 (1.20) 2.31 (1.21) 2.23 (1.17) 2.06 (1.17) 2.67 (1.05) 2.32 (1.37) 
Adherence to measures 2020 2.97 (1.00) 3.07 (0.94) 3.02 (0.92) 2.79 (1.07) 2.48 (1.03) 3.29 (0.83) 2.85 (0.94) 3.35 (0.80) 2.88 (1.14) 
 2021 2.90 (1.08) 2.97 (1.00) 3.06 (1.02) 2.68 (1.16) 2.41 (1.08) 3.17 (0.93) 2.87 (1.03) 3.22 (0.91) 2.83 (1.24) 
Communication (government, authorities) 
 Clear and understandable 2020 2.75 (1.29) 2.44 (1.22) 3.19 (1.16) 2.72 (1.27) 2.78 (1.35) 2.61 (1.28) 3.15 (1.33) 2.57 (1.24) 2.60 (1.30) 
2021 2.75 (1.28) 2.28 (1.14) 2.62 (1.19) 2.62 (1.25) 3.18 (1.32) 2.45 (1.19) 2.84 (1.33) 2.98 (1.27) 3.02 (1.28) 
 Credible and honest 2020 2.64 (1.30) 2.34 (1.18) 3.13 (1.18) 2.47 (1.28) 2.55 (1.31) 2.62 (1.33) 3.10 (1.37) 2.45 (1.27) 2.49 (1.26) 
2021 2.61 (1.30) 2.24 (1.16) 2.60 (1.22) 2.35 (1.26) 2.79 (1.32) 2.36 (1.19) 2.83 (1.34) 2.73 (1.32) 2.95 (1.36) 
 Guided by interests of people 2020 2.57 (1.25) 2.55 (1.22) 2.81 (1.14) 2.46 (1.25) 2.50 (1.34) 2.63 (1.27) 2.52 (1.18) 2.63 (1.23) 2.47 (1.33) 
 2021 2.55 (1.27) 2.41 (1.20) 2.41 (1.16) 2.31 (1.24) 2.76 (1.34) 2.29 (1.17) 2.56 (1.23) 2.73 (1.31) 2.94 (1.36) 
Feeling of being … by government, authorities 
 …well supported… 2020 2.62 (1.23) 2.51 (1.15) 2.97 (1.16) 2.42 (1.22) 2.39 (1.27) 2.63 (1.24) 2.59 (1.17) 2.76 (1.17) 2.65 (1.32) 
2021 2.52 (1.22) 2.31 (1.14) 2.51 (1.12) 2.14 (1.15) 2.59 (1.31) 2.25 (1.12) 2.38 (1.18) 2.94 (1.19) 2.98 (1.30) 
 …well informed… 2020 2.94 (1.29) 2.62 (1.18) 3.40 (1.15) 2.66 (1.25) 3.06 (1.33) 2.76 (1.33) 3.34 (1.29) 2.94 (1.20) 2.76 (1.33) 
2021 2.82 (1.26) 2.44 (1.14) 2.79 (1.20) 2.48 (1.21) 3.11 (1.29) 2.44 (1.17) 3.04 (1.30) 3.09 (1.20) 3.11 (1.31) 
 …taken seriously… 2020 2.70 (1.25) 2.54 (1.19) 3.02 (1.19) 2.44 (1.28) 2.62 (1.24) 2.69 (1.27) 2.69 (1.18) 2.79 (1.23) 2.78 (1.33) 
2021 2.66 (1.27) 2.35 (1.16) 2.54 (1.21) 2.26 (1.22) 2.91 (1.27) 2.32 (1.15) 2.58 (1.21) 3.04 (1.23) 3.20 (1.31) 
 …left alone… 2020 2.76 (1.34) 2.75 (1.34) 2.44 (1.26) 3.10 (1.35) 3.00 (1.42) 2.66 (1.34) 2.49 (1.36) 2.70 (1.21) 2.95 (1.33) 
2021 2.82 (1.32) 2.86 (1.33) 3.10 (1.32) 3.17 (1.37) 2.68 (1.34) 3.00 (1.33) 2.75 (1.29) 2.60 (1.17) 2.40 (1.21) 
Positive mental health 2020 17.38 (5.78) 16.90 (4.90) 17.91 (5.29) 17.58 (6.44) 15.77 (5.59) 17.51 (5.40) 17.38 (6.73) 17.27 (5.67) 18.85 (5.57) 
2021 16.71 (6.02) 16.23 (5.45) 16.68 (5.94) 17.04 (6.66) 16.36 (5.48) 16.83 (5.69) 16.14 (6.85) 16.49 (5.81) 17.92 (6.00) 
Depression symptoms 2020 5.17 (5.26) 4.03 (4.82) 4.20 (4.73) 6.62 (5.52) 6.26 (4.99) 5.51 (5.32) 4.26 (5.12) 5.51 (5.33) 4.86 (5.59) 
2021 5.39 (5.48) 4.72 (5.40) 4.97 (5.30) 6.54 (5.67) 5.76 (4.99) 6.09 (5.66) 4.86 (5.45) 5.09 (5.44) 5.20 (5.66) 
Anxiety symptoms 2020 3.53 (4.42) 2.94 (3.98) 2.58 (3.65) 5.17 (4.96) 4.60 (4.62) 4.02 (4.57) 2.65 (3.89) 2.79 (3.75) 3.59 (5.05) 
2021 3.92 (4.65) 3.68 (4.56) 3.18 (4.03) 5.20 (5.01) 4.59 (4.80) 4.64 (5.02) 3.40 (4.45) 2.87 (3.88) 3.93 (4.89) 
Stress symptoms 2020 5.80 (5.10) 5.03 (4.87) 4.54 (4.72) 7.15 (5.28) 7.23 (5.21) 6.46 (4.88) 4.55 (4.59) 5.86 (5.07) 5.43 (5.30) 
2021 6.01 (5.21) 5.60 (5.36) 5.50 (5.15) 7.07 (5.43) 6.70 (5.12) 7.12 (5.24) 5.52 (4.83) 5.24 (4.96) 5.41 (5.19) 
COVID-19 burden 2020 22.94 (7.25) 23.04 (6.69) 19.85 (7.13) 22.91 (6.92) 26.31 (7.36) 26.50 (6.60) 20.94 (7.10) 21.79 (6.63) 22.03 (6.74) 
2021 23.08 (7.59) 26.10 (7.02) 23.11 (7.57) 23.57 (7.35) 24.26 (7.67) 27.01 (6.76) 21.91 (7.16) 19.46 (6.69) 19.53 (6.87) 
YearM (SD)
allFRGEPLRUESSVUKUS
Usefulness of measures 2020 2.31 (1.16) 2.08 (1.08) 2.60 (1.16) 2.09 (1.13) 2.16 (1.21) 2.48 (1.14) 2.16 (1.20) 2.51 (1.00) 2.36 (1.24) 
2021 2.21 (1.22) 1.79 (1.12) 2.35 (1.26) 1.91 (1.20) 2.31 (1.21) 2.23 (1.17) 2.06 (1.17) 2.67 (1.05) 2.32 (1.37) 
Adherence to measures 2020 2.97 (1.00) 3.07 (0.94) 3.02 (0.92) 2.79 (1.07) 2.48 (1.03) 3.29 (0.83) 2.85 (0.94) 3.35 (0.80) 2.88 (1.14) 
 2021 2.90 (1.08) 2.97 (1.00) 3.06 (1.02) 2.68 (1.16) 2.41 (1.08) 3.17 (0.93) 2.87 (1.03) 3.22 (0.91) 2.83 (1.24) 
Communication (government, authorities) 
 Clear and understandable 2020 2.75 (1.29) 2.44 (1.22) 3.19 (1.16) 2.72 (1.27) 2.78 (1.35) 2.61 (1.28) 3.15 (1.33) 2.57 (1.24) 2.60 (1.30) 
2021 2.75 (1.28) 2.28 (1.14) 2.62 (1.19) 2.62 (1.25) 3.18 (1.32) 2.45 (1.19) 2.84 (1.33) 2.98 (1.27) 3.02 (1.28) 
 Credible and honest 2020 2.64 (1.30) 2.34 (1.18) 3.13 (1.18) 2.47 (1.28) 2.55 (1.31) 2.62 (1.33) 3.10 (1.37) 2.45 (1.27) 2.49 (1.26) 
2021 2.61 (1.30) 2.24 (1.16) 2.60 (1.22) 2.35 (1.26) 2.79 (1.32) 2.36 (1.19) 2.83 (1.34) 2.73 (1.32) 2.95 (1.36) 
 Guided by interests of people 2020 2.57 (1.25) 2.55 (1.22) 2.81 (1.14) 2.46 (1.25) 2.50 (1.34) 2.63 (1.27) 2.52 (1.18) 2.63 (1.23) 2.47 (1.33) 
 2021 2.55 (1.27) 2.41 (1.20) 2.41 (1.16) 2.31 (1.24) 2.76 (1.34) 2.29 (1.17) 2.56 (1.23) 2.73 (1.31) 2.94 (1.36) 
Feeling of being … by government, authorities 
 …well supported… 2020 2.62 (1.23) 2.51 (1.15) 2.97 (1.16) 2.42 (1.22) 2.39 (1.27) 2.63 (1.24) 2.59 (1.17) 2.76 (1.17) 2.65 (1.32) 
2021 2.52 (1.22) 2.31 (1.14) 2.51 (1.12) 2.14 (1.15) 2.59 (1.31) 2.25 (1.12) 2.38 (1.18) 2.94 (1.19) 2.98 (1.30) 
 …well informed… 2020 2.94 (1.29) 2.62 (1.18) 3.40 (1.15) 2.66 (1.25) 3.06 (1.33) 2.76 (1.33) 3.34 (1.29) 2.94 (1.20) 2.76 (1.33) 
2021 2.82 (1.26) 2.44 (1.14) 2.79 (1.20) 2.48 (1.21) 3.11 (1.29) 2.44 (1.17) 3.04 (1.30) 3.09 (1.20) 3.11 (1.31) 
 …taken seriously… 2020 2.70 (1.25) 2.54 (1.19) 3.02 (1.19) 2.44 (1.28) 2.62 (1.24) 2.69 (1.27) 2.69 (1.18) 2.79 (1.23) 2.78 (1.33) 
2021 2.66 (1.27) 2.35 (1.16) 2.54 (1.21) 2.26 (1.22) 2.91 (1.27) 2.32 (1.15) 2.58 (1.21) 3.04 (1.23) 3.20 (1.31) 
 …left alone… 2020 2.76 (1.34) 2.75 (1.34) 2.44 (1.26) 3.10 (1.35) 3.00 (1.42) 2.66 (1.34) 2.49 (1.36) 2.70 (1.21) 2.95 (1.33) 
2021 2.82 (1.32) 2.86 (1.33) 3.10 (1.32) 3.17 (1.37) 2.68 (1.34) 3.00 (1.33) 2.75 (1.29) 2.60 (1.17) 2.40 (1.21) 
Positive mental health 2020 17.38 (5.78) 16.90 (4.90) 17.91 (5.29) 17.58 (6.44) 15.77 (5.59) 17.51 (5.40) 17.38 (6.73) 17.27 (5.67) 18.85 (5.57) 
2021 16.71 (6.02) 16.23 (5.45) 16.68 (5.94) 17.04 (6.66) 16.36 (5.48) 16.83 (5.69) 16.14 (6.85) 16.49 (5.81) 17.92 (6.00) 
Depression symptoms 2020 5.17 (5.26) 4.03 (4.82) 4.20 (4.73) 6.62 (5.52) 6.26 (4.99) 5.51 (5.32) 4.26 (5.12) 5.51 (5.33) 4.86 (5.59) 
2021 5.39 (5.48) 4.72 (5.40) 4.97 (5.30) 6.54 (5.67) 5.76 (4.99) 6.09 (5.66) 4.86 (5.45) 5.09 (5.44) 5.20 (5.66) 
Anxiety symptoms 2020 3.53 (4.42) 2.94 (3.98) 2.58 (3.65) 5.17 (4.96) 4.60 (4.62) 4.02 (4.57) 2.65 (3.89) 2.79 (3.75) 3.59 (5.05) 
2021 3.92 (4.65) 3.68 (4.56) 3.18 (4.03) 5.20 (5.01) 4.59 (4.80) 4.64 (5.02) 3.40 (4.45) 2.87 (3.88) 3.93 (4.89) 
Stress symptoms 2020 5.80 (5.10) 5.03 (4.87) 4.54 (4.72) 7.15 (5.28) 7.23 (5.21) 6.46 (4.88) 4.55 (4.59) 5.86 (5.07) 5.43 (5.30) 
2021 6.01 (5.21) 5.60 (5.36) 5.50 (5.15) 7.07 (5.43) 6.70 (5.12) 7.12 (5.24) 5.52 (4.83) 5.24 (4.96) 5.41 (5.19) 
COVID-19 burden 2020 22.94 (7.25) 23.04 (6.69) 19.85 (7.13) 22.91 (6.92) 26.31 (7.36) 26.50 (6.60) 20.94 (7.10) 21.79 (6.63) 22.03 (6.74) 
2021 23.08 (7.59) 26.10 (7.02) 23.11 (7.57) 23.57 (7.35) 24.26 (7.67) 27.01 (6.76) 21.91 (7.16) 19.46 (6.69) 19.53 (6.87) 

2020: all: N = 7,658; France (FR): N = 940, Germany (GE): N = 917, Poland (PL): N = 924, Russia (RU): N = 986, Spain (ES): N = 960, Sweden (SV): N = 922, the UK (UK): N = 1,105, the USA (US): N = 904; 2021: All: N = 8,244; FR: N = 1,001, GE: N = 1,145, PL: N = 1,004, RU: N = 1,024, ES: N = 985, SV: N = 1,003, UK: N = 1,050, US: N = 1,032; M, mean; SD, standard deviation.

Table 3.

Simplified presentation of multivariate analyses of variance (2020 vs. 2021: year with the higher level of the assessed variable and the level of significance of the difference are presented)

AllFRGEPLRUESSVUKUS
1. MANOVA: p, η2p <0.001, 0.008 <0.001, 0.021 <0.001, 0.103 <0.001, 0.020 <0.001, 0.056 <0.001, 0.045 <0.001, 0.039 <0.001, 0.062 <0.001, 0.074 
Usefulness of measures 2020 (<0.001) 2020 (<0.001) 2020 (<0.001) 2020 (<0.001) 2021 (0.006) 2020 (<0.001)  2021 (<0.001)  
Adherence to measures 2020 (<0.001) 2020 (0.020)  2020 (0.041)  2020 (0.003)  2020 (<0.001)  
Communication (government, authorities) 
 Clear and understandable  2020 (0.005) 2020 (<0.001)  2021 (<0.001) 2020 (0.005) 2020 (<0.001) 2021 (<0.001) 2021 (<0.001) 
 Credible and honest  2020 (0.047) 2020 (<0.001) 2020 (0.043) 2021 (<0.001) 2020 (<0.001) 2020 (<0.001) 2021 (<0.001) 2021 (<0.001) 
 Guided by interests of people  2020 (0.009) 2020 (<0.001) 2020 (0.006) 2021 (<0.001) 2020 (<0.001)   2021 (<0.001) 
Feeling of being … by government, authorities 
 …well supported… 2020 (<0.001) 2020 (<0.001) 2020 (<0.001) 2020 (<0.001) 2021 (<0.001) 2020 (<0.001) 2020 (<0.001) 2021 (<0.001) 2021 (<0.001) 
 …well informed… 2020 (<0.001) 2020 (<0.001) 2020 (<0.001) 2020 (0.001)  2020 (<0.001) 2020 (<0.001) 2021 (0.005) 2021 (<0.001) 
 …taken seriously…  2020 (<0.001) 2020 (<0.001) 2020 (0.002) 2021 (<0.001) 2020 (<0.001)  2021 (<0.001) 2021 (<0.001) 
 …left alone… 2021 (0.005)  2021 (<0.001)  2020 (<0.001) 2021 (<0.001) 2021 (<0.001)  2020 (<0.001) 
2. MANOVA: p, η2p <0.001, 0.006 <0.001, 0.056 <0.001, 0.049 n.s <0.001, 0.024 0.031, 0.006 <0.001, 0.018 <0.001, 0.063 <0.001, 0.064 
Positive mental health 2020 (<0.001) 2020 (0.005) 2020 (<0.001)  2021 (0.019) 2020 (0.007) 2020 (0.014) 2020 (0.005) 2020 (<0.001) 
Depression symptoms 2021 (0.010) 2021 (0.003) 2021 (<0.001)  2020 (0.025) 2021 (0.020) 2021 (<0.001)   
Anxiety symptoms 2021 (<0.001) 2021 (<0.001) 2021 (<0.001)   2021 (0.004) 2021 (<0.001)   
Stress symptoms 2021 (0.011) 2021 (0.014) 2021 (<0.001)  2020 (0.020) 2021 (0.004) 2021 (0.003) 2020 (0.004)  
COVID-19 burden  2021 (<0.001) 2021 (<0.001)  2020 (<0.001)  2021 (<0.001) 2020 (0.030) 2020 (<0.001) 
AllFRGEPLRUESSVUKUS
1. MANOVA: p, η2p <0.001, 0.008 <0.001, 0.021 <0.001, 0.103 <0.001, 0.020 <0.001, 0.056 <0.001, 0.045 <0.001, 0.039 <0.001, 0.062 <0.001, 0.074 
Usefulness of measures 2020 (<0.001) 2020 (<0.001) 2020 (<0.001) 2020 (<0.001) 2021 (0.006) 2020 (<0.001)  2021 (<0.001)  
Adherence to measures 2020 (<0.001) 2020 (0.020)  2020 (0.041)  2020 (0.003)  2020 (<0.001)  
Communication (government, authorities) 
 Clear and understandable  2020 (0.005) 2020 (<0.001)  2021 (<0.001) 2020 (0.005) 2020 (<0.001) 2021 (<0.001) 2021 (<0.001) 
 Credible and honest  2020 (0.047) 2020 (<0.001) 2020 (0.043) 2021 (<0.001) 2020 (<0.001) 2020 (<0.001) 2021 (<0.001) 2021 (<0.001) 
 Guided by interests of people  2020 (0.009) 2020 (<0.001) 2020 (0.006) 2021 (<0.001) 2020 (<0.001)   2021 (<0.001) 
Feeling of being … by government, authorities 
 …well supported… 2020 (<0.001) 2020 (<0.001) 2020 (<0.001) 2020 (<0.001) 2021 (<0.001) 2020 (<0.001) 2020 (<0.001) 2021 (<0.001) 2021 (<0.001) 
 …well informed… 2020 (<0.001) 2020 (<0.001) 2020 (<0.001) 2020 (0.001)  2020 (<0.001) 2020 (<0.001) 2021 (0.005) 2021 (<0.001) 
 …taken seriously…  2020 (<0.001) 2020 (<0.001) 2020 (0.002) 2021 (<0.001) 2020 (<0.001)  2021 (<0.001) 2021 (<0.001) 
 …left alone… 2021 (0.005)  2021 (<0.001)  2020 (<0.001) 2021 (<0.001) 2021 (<0.001)  2020 (<0.001) 
2. MANOVA: p, η2p <0.001, 0.006 <0.001, 0.056 <0.001, 0.049 n.s <0.001, 0.024 0.031, 0.006 <0.001, 0.018 <0.001, 0.063 <0.001, 0.064 
Positive mental health 2020 (<0.001) 2020 (0.005) 2020 (<0.001)  2021 (0.019) 2020 (0.007) 2020 (0.014) 2020 (0.005) 2020 (<0.001) 
Depression symptoms 2021 (0.010) 2021 (0.003) 2021 (<0.001)  2020 (0.025) 2021 (0.020) 2021 (<0.001)   
Anxiety symptoms 2021 (<0.001) 2021 (<0.001) 2021 (<0.001)   2021 (0.004) 2021 (<0.001)   
Stress symptoms 2021 (0.011) 2021 (0.014) 2021 (<0.001)  2020 (0.020) 2021 (0.004) 2021 (0.003) 2020 (0.004)  
COVID-19 burden  2021 (<0.001) 2021 (<0.001)  2020 (<0.001)  2021 (<0.001) 2020 (0.030) 2020 (<0.001) 

2020: all: N = 7,658; France (FR): N = 940, Germany (GE): N = 917, Poland (PL): N = 924, Russia (RU): N = 986, Spain (ES): N = 960, Sweden (SV): N = 922, the UK (UK): N = 1,105, the USA (US): N = 904; 2021: All: N = 8,244; France (FR): N = 1,001, Germany (GE): N = 1,145, Poland (PL): N = 1,004, Russia (RU): N = 1,024, Spain (ES): N = 985, Sweden (SV): N = 1,003, the UK (UK): N = 1,050, the USA (US): N = 1,032; M, Mean; SD, standard deviation; MANOVA, multivariate analysis of variance; p = significance; ηp2 = effect size measure of the main effect; empty column = no significant difference between 2020 and 2021; in brackets: significance of the difference.

Both MANOVAs confirmed significant differences between the two data collections (see Table 3). In the overall samples, the rating of the introduced measures as useful and of adherence to them, the feeling of being well supported and well informed, as well as PMH, were significantly higher in 2020 than in 2021. In contrast, the feeling of being left alone, as well as symptoms of depression, anxiety, and stress, were significantly higher in 2021 than in 2020 (see Table 3).

In the country-specific samples, the first MONOVA showed that in four of the eight investigated countries (FR, GE, PL, ES), the rating of the introduced measures as useful was significantly higher in 2020 than in 2021. In Russia and the UK, it was significantly higher in 2021. Adherence to the measures was significantly higher in 2020 than in 2021 in France, Poland, Spain, and the UK (see Table 3).

For governmental communication and for how participants feel treated by the government and authorities, we found a similar result pattern in the five countries that belong to the European Union: France, Germany, Poland, Spain, and Sweden. Russia, the UK, and the USA showed an opposite result pattern. In the European Union countries, the rating of the governmental communication as clear and understandable (FR, GE, ES, SV), credible and honest (FR, GE, PL, ES, SV), and guided by interests of people (FR, GE, PL, ES) was significantly higher in 2020 than in 2021. In the non-European Union countries, its rating as clear and understandable (RU, UK, US), credible and honest (RU, UK, US), and guided by interests of people (RU, US) was significantly higher in 2021 than in 2020 (see Table 3).

In the European Union countries, the feeling of being well supported, well informed (both: FR, GE, PL, ES, SV), and taken seriously (FR, GE, PL, ES) by government and authorities was significantly higher in 2020 than in 2021, while the feeling of being left alone was significantly higher in 2021 than in 2020 (GE, ES, SV). In the non-European Union countries, the feeling of being well supported (RU, UK, US), well informed (UK, US), and taken seriously (RU, UK, US) was significantly higher in 2021 than in 2020, while the feeling of being left alone was significantly higher in 2020 than in 2021 (RU, US) (see Table 3).

In the second MANOVA, PMH was significantly higher in 2020 than in 2021 in six of the investigated countries (FR, GE, ES, SV, UK, US). In contrast, it was higher in 2021 than in 2020 in Russia. For the negative symptoms, we found a similar result pattern for four of the five European Union countries (FR, GE, ES, SV). Symptoms of depression, anxiety, and stress (all: FR, GE, ES, SV), as well as COVID-19 burden (FR, GE, SV), were significantly higher in 2021 than in 2020. In contrast, symptoms of depression (RU) and stress (RU, UK), as well as COVID-19 burden (RU, UK, US), were significantly higher in 2020 than in 2021 in non-European Union countries. There were no significant mental health differences in Poland between 2020 and 2021 (see Table 3).

Adherence to COVID-19 mitigation measures can speed up the global return to a “normal” life (a life without infection fear and restrictions of everyday life caused by the pandemic) [12]. The perception of the measures as useful is an important positive predictor of adherence [7]. The present study compared two population-representative datasets from eight countries and revealed significant changes in usefulness perception and adherence to COVID-19 mitigation measures, as well as of their potential predictors between the years 2020 and 2021.

In the overall samples, the perception of usefulness of the measures and the adherence to them were higher in 2020 than in 2021. The country-specific analyses showed mostly the same result pattern. An exception was the higher usefulness perception in 2021 than in 2020 in Russia and the UK. However, this change was not accompanied by a higher adherence level in 2021 than in 2020.

Following considerations at least partly explain this finding. At the beginning of the pandemic in 2020, trust in the governmental measures and the motivation to adhere to them were enhanced among people in many countries driven by the hope that the pandemic state would be quickly over [51]. However, the pandemic and the restrictive measures were still not over in 2021 [52]. Moreover, the validity of the mitigation measures changed permanently in all countries except Sweden [33]. During the data collection in May 2021, there were still bans on public gathering in most of the investigated countries; a “stay-at-home” was mainly mandatory or at least recommended, except in Russia; and the wearing of face masks was still required [33]. This could reduce the trust and motivation of the population [53]. Furthermore, previous research showed that the adherence level can differ depending on the specific measures [54]. Notably, the mitigation measures in 2020 mostly referred to less invasive actions such as the wearing of face masks in seven of the investigated countries [33]. In 2021, vaccination became one of the most important COVID-19 mitigation measures in the investigated countries that is more invasive than the other measures [55, 56]. Less invasive measures were associated with higher adherence than more invasive measures such as vaccination that was treated with high skepticism and rejection by some people [53, 57]. In the present study, usefulness perception and adherence to the COVID-19 measures were assessed very generally with, respectively, one item. Therefore, we can only hypothesize that the higher usefulness perception and adherence in 2020 than in 2021 could be due to the differences in the required mitigation measures.

Furthermore, in the overall sample, variables that were previously shown to increase usefulness perception and adherence to the measures (i.e., PMH, feeling of being well supported and well informed by the government) [7, 28] were lower in 2021 than in 2020. In contrast, variables that predicted them negatively (i.e., depression, anxiety, and stress symptoms, feeling of being left alone) [13] were higher in 2021 than in 2020. This could also contribute to the explanation of the lower level of usefulness perception and adherence in 2021 than in 2020.

The country-specific results indicated a differentiation between European Union and non-European Union countries. In France, Germany, Poland, Spain, and Sweden – the five European Union countries – the rating of the governmental communication on the COVID-19 situation was less positive and trustful in 2021 than in 2020. The population in these countries felt less support by the government in 2021 than in 2020. And specifically in Germany, Spain, and Sweden, the feeling of being left alone was higher in 2021 than in 2020. The same result pattern in the European Union countries is interesting considering that the course of the infection rates differed between the countries [58]. For example, Spain was affected especially strongly at the beginning of the pandemic. In Germany, a remarkable rise of COVID-19 cases was much later in winter 2020 [58]. Furthermore, even though the governments of all countries introduced similar mitigation measures – except Sweden – there were no general Europe-wide regulations on the measures [59]. Each government decided on its own which measures to introduce (e.g., [60‒62]). Moreover, the feeling of European unity is supported by open national borders and free mobility between the countries [63]. This feeling was disrupted when many borders were temporarily closed to slow down the pandemic spread [64, 65]. Nevertheless, the present findings allow the assumption that in all five European Union countries, trust in the governmental COVID-19 actions decreased over time which could also reduce the usefulness perception and the adherence to the mitigation measures.

In contrast, the present findings show that in Russia, the UK, and the USA – the three non-European Union countries – the rating of the governmental COVID-19 communication was more positive and trustful in 2021 than in 2020. The population of these countries felt more supported by the government in 2021 than in 2020. In the USA, there was a presidential election in the second part of 2020 that resulted in a change of the president and further governmental changes. This could be a confounded variable that was not controlled for in the present study which could at least partly influence the perception of the governmental communication and actions [66]. However, there were no such significant governmental changes between 2020 and 2021 in Russia and in the UK that could explain the present findings. Notably, some mitigation measures such as the wearing of face masks in public places were similar in the three non-European Union countries in May 2021. Other measures such as the ban on public events and gatherings were country-specific. While the ban was valid in Russia and the UK, a cancellation of public events was only recommended in the USA [33].

In line with the dual-factor models [15], both dimensions of mental health showed an own specific result-pattern. In most European Union and non-European Union countries, PMH was higher in 2020 than in 2021. Only in Russia, a reversed pattern was found. The negative mental health variables were higher in 2021 than in 2020 in most of the included European Union countries. This finding confirms available research that described an increase of depression and anxiety symptoms, for example, in Germany [67] and Spain [68] since the pandemic outbreak. Following recent literature [21], this could be a longitudinal consequence of the psychological burden caused by COVID-19. Notably, in the overall sample as well as in France, Germany, and Sweden, the burden level was higher in 2021 than in 2020. However, in non-European Union countries, the negative dimension of mental health and the burden level were higher in 2020 than in 2021. This contradicts earlier studies that showed an increase of depression, anxiety and stress symptoms in the UK [69], the USA [70], and Russia [71] during the pandemic.

The following considerations could explain this difference at least partly. Notably, most recent research on mental health changes during the pandemic focused on specific population groups such as students or health-care workers [72, 73]. In the present study, we investigated representative samples. The found difference allows the hypothesis that, especially in non-European Union countries, the trajectories of the pandemic’s impact on mental health could depend on the specificity of the investigated sample. Therefore, general conclusions on their population could be less precise and conclusive. This hypothesis should be investigated by future research that compares changes in mental health between population-representative samples and, for example, representants of specific occupations in non-European Union countries.

The present study has some limitations. First, both datasets were distinct from each other. Thus, even though they consisted of population-representative samples, conclusions on changes of the investigated variables over time should be drawn with caution. An investigation of potential within-person changes would provide more reliable findings on differences of the investigated variables between the years 2020 and 2021. Moreover, the data were collected by the marketing and research institute YouGov. YouGov used quota samples to achieve representativity. However, only people who have a panel account can be invited to a survey. Therefore, we cannot exclude a self-selection bias. Second, previous research showed that adherence to the COVID-19 mitigation measures can differ depending on the specific measure [54]. In the present study, general usefulness perception and adherence to the measures were assessed, respectively, by one item only that has not previously been validated in other studies. The unspecific measures do not allow conclusions on specific measures. Third, no Asian, African, and South American countries were included in the investigation that limits the global generalizability of the present findings. Fourth, previous research showed that the type of media used as information source about the COVID-19 situation as well as the amount of time spent on media use can influence a person’s trust in national governments’ and authorities’ actions. In the present study, the information on participants' media use and, therefore, its influence as a potential confounder is missing. Overall, potential confounder variables were not considered in the present study.

New mutations of the coronavirus complicate the fight against the pandemic [74]. This increases the significance of adherence to the COVID-19 mitigation measures [75, 76]. Our explorative results reveal no increase in adherence between 2020 and 2021 in the eight investigated countries. In contrast, we found that in 2021, the level of adherence to the measures was significantly lower than in 2020 in countries such as France, Poland, Spain, and the UK Predictors of adherence such as the usefulness perception of the measures, the rating of the governmental COVID-19 communication, and how people feel threatened were less positive in 2021 than in 2020 in European Union countries. In contrast, these factors became more positive in non-European Union countries such as Russia, the UK, and the USA. In Russia, the level of mental health was higher in 2021 than in 2020, while it decreased in other countries.

Against this background, especially governments and authorities in European Union countries should consider how to enhance the population trust in their COVID-19-related decisions. More public relation work is required. It should be worked on for a clearer and more understandable public explanation of the governmental COVID-19 actions, their short- and long-term sense should be described, and it should be disclosed how the interests of the population enter the governmental decisions. Governmental campaigns should try to foster the feelings of support among the population. Furthermore, a stronger focus on the improvement of mental health – decrease of depression, anxiety, and stress symptoms, increase of PMH – is necessary. There is a strong need for more low-threshold access to mental health programs and psychotherapeutic treatment. In addition, public advertising campaigns offline and on social media should promote ways of self-care mental health protection such as keeping daily routine, sleep hygiene, healthy nutrition, and more social interaction with family members who live in the same home (e.g., playing board games) [77, 78]. Also, a conscious setting of time limits for daily use of social media has been described as an important mental health protection step [79]. Time that becomes free from online activity can be used for engagement in physical activity (e.g., jogging, yoga) that does not require cost-intensive equipment and can be engaged in without a violation of social distancing [80, 81]. These steps are important for people’s mental health during the pandemic and in non-pandemic situations. They could foster adherence to the COVID-19 measures among the population and thus contribute to the pandemic fight.

The Ethics Committee of the Faculty of Psychology of the Ruhr-Universität Bochum approved the implementation of the present study (approval number: 118 and 118 extended). YouGov obtained the required permits and approvals for the data collection in all included countries. Both data collections were pre-registered with AsPredicted.org (1) May 25, 2020: Pre-registration number: #41686; see https://aspredicted.org/e7a9g.pdf; (2) May 05, 2021: Pre-registration number: #64865; see https://aspredicted.org/blind.php?x=j7jk4s). All procedures performed in this study were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards. The present study was endorsed by DZPG (German Center for Mental Health). All participants were properly instructed and gave online their informed consent to participate by clicking a box. This procedure has been explicitly approved by the responsible ethics committee.

The authors have no conflicts of interest to declare.

The authors did not receive support from any organization for the submitted work.

Julia Brailovskaia, Silvia Schneider, and Jürgen Margraf conducted the study design. Julia Brailovskaia wrote the first draft of the manuscript. Julia Brailovskaia and Xiao Chi Zhang conducted statistical analysis. Julia Brailovskaia conducted literature searches, data collection, and data preparation. Jürgen Margraf reviewed and edited the first draft. All authors contributed to and have approved the final manuscript and state their compliance with the Code of Ethics of the World Medical Association (Declaration of Helsinki).

The dataset will be available from the corresponding author on reasonable request. Research data are not publicly available on ethical grounds.

1.
Tso RV, Cowling BJ. Importance of face masks for COVID-19: a call for effective public education. Clin Infect Dis. 2020;71(16):2195–8.
2.
Wright L, Steptoe A, Mak HW, Fancourt D. Do people reduce compliance with COVID-19 guidelines following vaccination? A longitudinal analysis of matched UK adults. J Epidemiol Community Health. 2022;76(2):109–15.
3.
Androniceanu A.Major structural changes in the EU policies due to the problems and risks caused by COVID-19. Administratie Management Pub; 2020. Vol. 34. p. 137–49.
4.
Liang L-L, Tseng C-H, Ho HJ, Wu C-Y. Covid-19 mortality is negatively associated with test number and government effectiveness. Sci Rep. 2020;10(1):12567–7.
5.
Howard J, Huang A, Li Z, Tufekci Z, Zdimal V, van der Westhuizen H-M, et al. An evidence review of face masks against COVID-19. Proc Natl Acad Sci USA. 2021;118(4):e2014564118.
6.
Margraf J, Brailovskaia J, Schneider S. Adherence to behavioral Covid-19 mitigation measures strongly predicts mortality. PLoS One. 2021;16(3):e0249392.
7.
Margraf J, Brailovskaia J, Schneider S. Behavioral measures to fight COVID-19: an 8-country study of perceived usefulness, adherence and their predictors. PLoS One. 2020;15(12):e0243523.
8.
Lazarus JV, Ratzan SC, Palayew A, Gostin LO, Larson HJ, Rabin K, et al. A global survey of potential acceptance of a COVID-19 vaccine. Nat Med. 2020;27(2):225–8.
9.
Schaner S, Theys N, Angrisani M, Banerjee J, Khobragade PY, Petrosyan S, et al. Adherence to COVID-19 protective behaviours in India from May to December 2020: evidence from a nationally representative longitudinal survey. BMJ Open. 2022;12(2):e058065.
10.
Berg-Beckhoff G, Dalgaard Guldager J, Tanggaard Andersen P, Stock C, Smith Jervelund S. What predicts adherence to governmental COVID-19 measures among Danish students?Int J Enviro Res Pub Health. 2021;18(4):1822.
11.
Wright L, Steptoe A, Fancourt D. Predictors of self-reported adherence to COVID-19 guidelines. A longitudinal observational study of 51,600 UK adults. Lancet Reg Health Eur. 2021;4:100061.
12.
Júnior A, Dula J, Mahumane S, Koole O, Enosse S, Fodjo JNS, et al. Adherence to COVID-19 preventive measures in Mozambique: two consecutive online surveys. Int J Enviro Res Pub Health. 2021;18(3):1091.
13.
Lavallee KL, Brailovskaia J, Scholten S, Schneider S, Margraf J. Perceptions of macro- and micro-level factors predict COVID-19 self-reported health and safety guidelines adherence: a study across eight countries. Eur J Psychol Open. 2021;80(4):152–64.
14.
Shewasinad Yehualashet S, Asefa KK, Mekonnen AG, Gemeda BN, Shiferaw WS, Aynalem YA, et al. Predictors of adherence to COVID-19 prevention measure among communities in North Shoa Zone, Ethiopia based on health belief model: a cross-sectional study. PLoS One. 2021;16(1):e0246006.
15.
Keyes CLM. Mental illness and/or mental health? Investigating axioms of the complete state model of health. J Consult Clin Psychol. 2005;73(3):539–48.
16.
Suldo SM, Shaffer EJ. Looking beyond psychopathology: the dual-factor model of mental health in youth. Sch Psych Rev. 2008;37(1):52–68.
17.
Bueno-Notivol J, Gracia-García P, Olaya B, Lasheras I, López-Antón R, Santabárbara J. Prevalence of depression during the COVID-19 outbreak: a meta-analysis of community-based studies. Int J Clin Health Psychol. 2021;21(1):100196.
18.
Salari N, Hosseinian-Far A, Jalali R, Vaisi-Raygani A, Rasoulpoor S, Mohammadi M, et al. Prevalence of stress, anxiety, depression among the general population during the COVID-19 pandemic: a systematic review and meta-analysis. Glob Health. 2020;16(1):57–11.
19.
Lukat J, Margraf J, Lutz R, van der Veld WM, Becker ES. Psychometric properties of the Positive Mental Health Scale (PMH-scale). BMC Psychol. 2016;4(1):8.
20.
Capaldi CA, Liu L, Dopko RL. Positive mental health and perceived change in mental health among adults in Canada during the second wave of the COVID-19 pandemic. Res Policy Practice. 2021;41(11):359–77.
21.
Bäuerle A, Steinbach J, Schweda A, Beckord J, Hetkamp M, Weismüller B, et al. Mental health burden of the CoViD-19 outbreak in Germany: predictors of mental health impairment. J Prim Care Community Health. 2020;11:2150132720953682.
22.
Brailovskaia J, Cosci F, Mansueto G, Margraf J. The relationship between social media use, stress symptoms and burden caused by Coronavirus (Covid-19) in Germany and Italy: a cross-sectional and longitudinal investigation. J Affect Disord Rep. 2021;3:100067.
23.
Brailovskaia J, Margraf J. Predicting adaptive and maladaptive responses to the Coronavirus (COVID-19) outbreak: a prospective longitudinal study. Int J Clin Health Psychol. 2020;20(3):183–91.
24.
Brailovskaia J, Margraf J. Relationship between sense of control, psychological burden, sources of information and adherence to anti-COVID-19 rules. J Affect Disord Rep. 2022;8:100317.
25.
Pollak Y, Dayan H, Shoham R, Berger I. Predictors of non-adherence to public health instructions during the COVID-19 pandemic. Psychiatry Clin Neurosci. 2020;74(11):602–4.
26.
Scholten S, Velten J, Margraf J. Mental distress and perceived wealth, justice and freedom across eight countries: the invisible power of the macrosystem. PLoS One. 2018;13(5):e0194642.
27.
Scholten S, Velten J, Neher T, Margraf J. Wealth, justice and freedom: objective and subjective measures predicting poor mental health in a study across eight countries. SSM Popul Health. 2017;3:639–48.
28.
Brailovskaia J, Schneider S, Margraf J. To vaccinate or not to vaccinate!? Predictors of willingness to receive Covid-19 vaccination in Europe, the U.S., and China. PLoS One. 2021;16(12):e0260230.
29.
Beltekian D, Gavrilov D, Giattino C, Hasell J, Macdonald B, Mathieu E, et al. Covid-19-data. 2023 [cited 2023 July 14]. Available from: https://github.com/owid/covid-19-data/tree/master/public/data.
30.
World Health Organization. WHO Coronavirus (COVID-19) Dashboard 2023 [cited 2023 July 14]. Available from: https://covid19.who.int/.
31.
Gershman J. A guide to state coronavirus reopenings and lockdowns. The Wall Street Journal; 2020. [cited 2023 July 14]. Available from: https://www.wsj.com/articles/a-state-by-state-guide-to-coronavirus-lockdowns-11584749351?mod=theme_coronavirus-ribbon.
32.
Robert Koch Institut. Täglicher Lagebericht des RKI zur Coronavirus-Krankheit-2019 (COVID-19), 23.03.2020 – aktualisierter Stand für Deutschland 2020 [cited 2023 July 14]. Available from: : https://www.rki.de/DE/Content/InfAZ/N/Neuartiges_Coronavirus/Situationsberichte/2020-03-23-de.pdf?__blob=publicationFile.
33.
Mathieu E, Ritchie H, Rodés-Guirao L, Appel C, Gavrilov D, Giattino C, et al. Policy responses to the coronavirus pandemic. Our Wotld in Data 2023 [cited 2023 July 14]. Available from: https://ourworldindata.org/policy-responses-covid.
34.
Nohl A, Afflerbach C, Lurz C, Brune B, Ohmann T, Weichert V, et al. Acceptance of COVID-19 vaccination among front-line health care workers: a nationwide survey of emergency medical services personnel from Germany. Vaccin. 2021;9(5):424–235.
35.
Sherman SM, Smith LE, Sim J, Amlôt R, Cutts M, Dasch H, et al. COVID-19 vaccination intention in the UK: results from the COVID-19 vaccination acceptability study (CoVAccS), a nationally representative cross-sectional survey. Hum Vaccin Immunother. 2021;17(6):1612–21.
36.
Rodríguez-Blanco N, Montero-Navarro S, Botella-Rico JM, Felipe-Gómez AJ, Sánchez-Más J, Tuells J. Willingness to Be vaccinated against COVID-19 in Spain before the start of vaccination: a cross-sectional study. Inter J Environ Res Pub Health. 2021;18(10):5272–87.
37.
Eurostat. Task. Force on core social variables. Luxembourg: Office for official publications of the European Communities; 2007.
38.
Hoffmeyer-Zlotnik JHP, Warner U. Harmonisierung demographischer und sozioökonomischer Variablen. Heidelberg: Springer; 2012.
39.
Elo IT. Social class differentials in health and mortality: patterns and explanations in comparative perspective. Annu Rev Socio. 2009;35(1):553–72.
40.
Lund C, Breen A, Flisher AJ, Kakuma R, Corrigall J, Joska JA, et al. Poverty and common mental disorders in low and middle income countries: a systematic review. Soc Sci Med. 2010;71(3):517–28.
41.
Velten J, Brailovskaia J, Margraf J. Positive Mental Health Scale: validation and measurement invariance across eight countries, genders, and age groups. Psychol Assess. 2022;34(4):332–40.
42.
Lovibond PF, Lovibond SH. The structure of negative emotional states: comparison of the Depression Anxiety Stress Scales (DASS) with the beck depression and anxiety inventories. Behav Res Ther. 1995;33(3):335–43.
43.
Scholten S, Velten J, Bieda A, Zhang XC, Margraf J. Testing measurement invariance of the Depression, Anxiety, and Stress Scales (DASS-21) across four countries. Psychol Assess. 2017;29(11):1376–90.
44.
Bibi A, Lin M, Zhang XC, Margraf J. Psychometric properties and measurement invariance of depression, anxiety and stress scales (DASS-21) across cultures. Int J Psychol. 2020;55(6):916–25.
45.
Oei TPS, Sawang S, Goh YW, Mukhtar F. Using the Depression Anxiety Stress Scale 21 (DASS-21) across cultures. Int J Psychol. 2013;48(6):1018–29.
46.
Bieda A, Hirschfeld G, Schönfeld P, Brailovskaia J, Zhang XC, Margraf J. Universal happiness? Cross-cultural measurement invariance of scales assessing positive mental health. Psychol Asses. 2017;29(4):408–21.
47.
Brailovskaia J, Cosci F, Mansueto G, Miragall M, Herrero R, Baños RM, et al. The association between depression symptoms, psychological burden caused by Covid-19 and physical activity: an investigation in Germany, Italy, Russia, and Spain. Psychiatr Res. 2021;295:113596.
48.
Berry JW. Introduction to methodology. In: Triandis H, Berry JW, editors. Handbook of cross-cultural psychology 2. Boston: Allyn &amp; Bacon; 1989. p. 1–28.
49.
IBM Corp. IBM SPSS statistics for Windows, version 28.0. Armonk, (NY): IBM Corp; 2021.
50.
Stevens JP. Power of the multivariate analysis of variance tests. Psychol Bull. 1980;88(3):728–37.
51.
Bromme R, Mede NG, Thomm E, Kremer B, Ziegler R. An anchor in troubled times: trust in science before and within the COVID-19 pandemic. PloS One. 2022;17(2):e0262823.
52.
Hartmann M, Müller P. Acceptance and adherence to COVID-19 preventive measures are shaped predominantly by conspiracy beliefs, mistrust in science and fear: a comparison of more than 20 psychological variables. Psychol Rep. 2023;126(4):1742–83.
53.
Warren GW, Lofstedt R. Risk communication and COVID-19 in Europe: lessons for future public health crises. J Risk Res. 2022;25(10):1161–75.
54.
Petherick A, Goldszmidt R, Andrade EB, Furst R, Hale T, Pott A, et al. A worldwide assessment of changes in adherence to COVID-19 protective behaviours and hypothesized pandemic fatigue. Nat Hum Behav. 2021;5(9):1145–60.
55.
Neumann-Böhme S, Varghese NE, Sabat I, Barros PP, Brouwer W, van Exel J, et al. Once we have it, will we use it? A European survey on willingness to be vaccinated against COVID-19. Springer; 2020.
56.
Alley SJ, Stanton R, Browne M, To QG, Khalesi S, Williams SL, et al. As the pandemic progresses, how does willingness to vaccinate against COVID-19 evolve?Int J Environ Res Pub Health. 2021;18(2):797.
57.
Verger P, Scronias D, Dauby N, Adedzi KA, Gobert C, Bergeat M, et al. Attitudes of healthcare workers towards COVID-19 vaccination: a survey in France and French-speaking parts of Belgium and Canada, 2020. Eurosurveillance. 2021;26(3):2002047–8.
58.
Hasell J, Mathieu E, Beltekian D, Macdonald B, Giattino C, Ortiz-Ospina E, et al. A cross-country database of COVID-19 testing. Sci Data. 2020;7(1):345–7.
59.
Hantrais L, Letablier M-T. Comparing and contrasting the impact of the COVID-19 pandemic in the European Union. Routledge; 2020.
60.
Government of Poland. Koronawirus: informacje i zalecenia 2020 [cited 2023 July 14]. Available from: https://www.gov.pl/web/koronawirus.
61.
France Gournement. Covid-19. Toutes les informations essentielles sur la situation sanitaire 2020 [cited 2023 July 14]. Available from: https://www.gouvernement.fr/.
62.
Koch Institut Robert. COVID-19 (Coronavirus SARS-CoV-2) 2021 [cited 2023 July 14]. Available from: https://www.rki.de/DE/Content/InfAZ/N/Neuartiges_Coronavirus/nCoV.html.
63.
Mannin M. Pushing back the boundaries: the European Union and central and eastern Europe. Manchester (UK): Manchester University Press; 1999.
64.
Opiłowska E. The Covid-19 crisis: the end of a borderless Europe?Eur Soc. 2021;23(Suppl 1):S589–S600.
65.
Schimmelfennig F. Rebordering Europe: external boundaries and integration in the European Union. J Eur Public Policy. 2021;28(3):311–30.
66.
Baccini L, Brodeur A, Weymouth S. The COVID-19 pandemic and the 2020 US presidential election. J Popul Econ. 2021;34(2):739–67.
67.
Brailovskaia J, Teismann T, Friedrich S, Schneider S, Margraf J. Suicide ideation during the COVID-19 outbreak in German university students: comparison with pre-COVID 19 rates. J Affect Dis Rep. 2021;6:100228.
68.
Ausín B, González-Sanguino C, Castellanos MA, Sáiz J, Zamorano S, Vaquero C, et al. The psychological impact of the COVID-19 pandemic in Spain: a longitudinal study. Psicothema. 2022;34(1):66–73.
69.
Shevlin M, McBride O, Murphy J, Miller JG, Hartman TK, Levita L, et al. Anxiety, depression, traumatic stress and COVID-19-related anxiety in the UK general population during the COVID-19 pandemic. BJPsych Open. 2020;6(6):e125–9.
70.
Venanzi L, Dickey L, Green H, Pegg S, Benningfield MM, Bettis AH, et al. Longitudinal predictors of depression, anxiety, and alcohol use following COVID-19-related stress. Stress Health. 2022;38(4):679–91.
71.
Zinchenko YP, Shaigerova LA, Almazova OV, Shilko RS, Vakhantseva OV, Dolgikh AG, et al. The spread of COVID-19 in Russia: immediate impact on mental health of university students. Psychol Stud. 2021;66(3):291–302.
72.
Sobregrau Sangrà P, Aguiló Mir S, Castro Ribeiro T, Esteban-Sepúlveda S, García Pagès E, López Barbeito B, et al. Mental health assessment of Spanish healthcare workers during the SARS-CoV-2 pandemic. A cross-sectional study. Compr Psychiatry. 2022;112:152278.
73.
Tuncer AM. The effect of the COVID-19 pandemic on healthcare workers. Adv Appl Sociol. 2022;12(02):29–33.
74.
Karim SSA, Karim QA. Omicron SARS-CoV-2 variant: a new chapter in the COVID-19 pandemic. Lancet. 2021;398(10317):2126–8.
75.
Mahase E. Covid-19: omicron and the need for boosters. Brit Med J. 2021;2082:374–5.
76.
Del Rio C, Omer SB, Malani PN. Winter of omicron: the evolving COVID-19 pandemic. JAMA. 2022;327(4):319–20.
77.
Chouchou F, Augustini M, Caderby T, Caron N, Turpin NA, Dalleau G. The importance of sleep and physical activity on well-being during COVID-19 lockdown: reunion island as a case study. Sleep Med. 2021;77:297–301.
78.
Williams CYK, Townson AT, Kapur M, Ferreira AF, Nunn R, Galante J, et al. Interventions to reduce social isolation and loneliness during COVID-19 physical distancing measures: a rapid systematic review. PLoS One. 2021;16(2):e0247139.
79.
Brailovskaia J, Swarlik VJ, Grethe GA, Schillack H, Margraf J. Experimental longitudinal evidence for causal role of social media use and physical activity in COVID-19 burden and mental health. Z Gesundh Wiss. 2022;1–14.
80.
Brailovskaia J, Zhang XC, Cai D, Lu S, Gao ZH, Margraf J. The benefits of physical activity and positive mental health for reducing the burden of COVID-19: validation from a cross-sectional and longitudinal investigation in China and Germany. Int J Ment Health Addict. 2023;21(2):1186–99.
81.
Dwyer MJ, Pasini M, De Dominicis S, Righi E. Physical activity: benefits and challenges during the COVID-19 pandemic. Scand J Med Sci Sports. 2020;30(7):1291–4.