J o u r n a l P r e -p r o o f 2012; Sanzcarrillo, Garciacampayo, Rubio, Santed, & Montoro, 2002) . Besides, according to terror management theory, self-esteem is the main force to buffer against anxiety (Burke, Martens, & Faucher, 2010; Rosenblatt, Greenberg, Solomon, Pyszczynski, & Lyon, 1989) . A meta-analysis of longitudinal studies has provided support for this theory, showing that higher self-esteem significantly predicted lower levels of anxiety (Sowislo & Orth, 2013) . Importantly, many studies demonstrated that collective self-esteem could buffer better against anxiety when the importance of collectivity was recognized (Gupta, Rogers-Sirin, Okazaki, Ryce, & Sirin, 2014; Lam, 2007; Xie, Leong, & Feng 2008; Zhang, 2005) . Therefore, we assume that collective self-esteem could reduce the perceived stress by relieving anxiety.
It is worth mentioning that perceived social support and anxiety are not separate mediators. According to the cognitive theory of emotion, negative emotions (anxiety) usually arise when we appraise our life pessimistically. (Beck, 1971; Folkman & Lazarus, 1985; Oatley & Johnsonlaird, 1987) . Social support can help people reinterpret events or problems in a more positive and constructive light, which helps relieve anxiety (House, Umberson, & Landis, 1988; Thoits, 1995) . Therefore, collective self-esteem may reduce perceived stress through the chain mediation of perceived social support and anxiety.
J o u r n a l P r e -p r o o f the perceived stress through the indirect paths of perceived social support and anxiety separately, and their chain mediating path. The proposed multiple mediation model is shown in Figure 1 . Compared with the traditional simple mediating effect, the multiple mediating effect in this study is more likely to reveal the complex mechanism between collective self-esteem and perceived stress, which can guide subsequent research. Furthermore, the current study will identify the important factors buffering perceived stress, and their relationship, which helps enact psychological interventions for the non-infected general public during COVID-19. Figure 2 shows the development trend of the COVID-19 pandemic in China from February 4 to March 9, 2020. Existing confirmed cases continued to increase until February 17 and then decreased. Our survey was conducted from February 18 to February 25, 2020, a period when the existing confirmed cases gradually declined in number.
A total of 2023 participants were recruited to complete the questionnaire via an online survey platform called "SurveyStar," from February 18 to 25, 2020. Among them, 102 participants (13 unhealthy participants (e.g., with a fever), 1 suspected case, J o u r n a l P r e -p r o o f program failure during data collection, 968 participants did not report their gender.
The remaining 953 participants constituted 291 males and 662 females. 82.9% (n = 1593) of participants had a college degree or above. Participants were asked to choose "Yes" or "No" on their work status (e.g., Do you start to work outside the home?), and only 13.0% (n = 250) of participants had started to work outside the home.
Besides, participants were asked to rate their attention to COVID-19 (e.g., to what extent do you take an interest in information on COVID-19?) from 1 (little) to 5 (extreme), and 71.9% (n = 1381) of them paid great attention (more than or equal 4) to COVID-19. All participants provided written informed consent and were paid 5 yuan (approximately $0.70 US) as an incentive. The study was approved by the local institutional review board (Grant No. IRB20200218).
Collective self-esteem was assessed by CSES (Luhtanen & Crocker, 1992) , which includes 16 items. Each item was rated from 1 (strongly disagree) to 7 (strongly agree), with higher scores indicating higher collective self-esteem. Moreover, the collectivity in the current study referred to the country (questions such as "I am a worthy member of the country I belong to", and "I feel good about the country I belong to"). Cronbach's α for the present study was 0.88.
Journal Pre-proof J o u r n a l P r e -p r o o f Perceived social support was measured by PSSS (Zimet, Powell, Farley, Werkman, & Berkoff, 1990 ). There are 12 items, which are rated from 1 (strongly disagree) to 7 (strongly agree), with higher scores indicating higher perceived social support (questions such as "There are some people in my life who care about my feelings").
Cronbach's α for the present study was 0.91.
Levels of anxiety during the previous seven days were measured by the 20-item SAS (Zung, 1971) . All responses were distributed on a 4-point Likert scale (1 = never, 4 = very often), with higher scores indicating higher levels of anxiety (questions such as "I feel more nervous and anxious than usual"). Cronbach's α for the present study was 0.80.
J o u r n a l P r e -p r o o f was conducted (see Table 2 and Figure 3 ). Results showed that higher collective self-esteem significantly predicted higher perceived social support (B = 0.35, t = 19.97, p < 0.001; see Model 1 of Table 2 Table 2) After controlling for perceived social support and anxiety, collective self-esteem could significantly predict perceived stress, which indicates that perceived social support and anxiety were partial mediators between collective self-esteem and Consistent with our hypothesis, collective self-esteem was effective in reducing perceived stress. In general, individuals with higher self-esteem could respond better to threats and frustrations, which is important for reducing perceived stress (Abouserie, 1994; Hubbs et al., 2012; Hudd et al., 2000; Kesting et al., 2013) .
Importantly, a serious catastrophe can be more effectively addressed by the collectivity (Tziner, 1982; Wang et al., 2020) ; therefore, we may speculate that the relationship between collective self-esteem and perceived stress may be enhanced during COVID-19. Finally, the collectivity in the current study referred to the country, which indicated the individual's value assessment of their own country and their citizenship of this country can effectively reduce perceived stress during COVID-19.
Multiple mediating analysis further revealed the reasons why collective self-esteem could reduce perceived stress. The first reason is individuals with higher collective self-esteem could perceive more social support. Social support is defined as an important resource deriving from the social relationship, which means a good social relationship is the precondition of more social support (Heaney & Israel, 2008).
Individuals with higher collective self-esteem usually emphasize their social relationships and tend to ask for help when facing difficulties (Barker, 2009;  Journal Pre-proof J o u r n a l P r e -p r o o f Gangadharbatla, 2008) , which, arguably, makes them perceive more social support during COVID-19. Furthermore, perceived stress is essentially a sense of uncontrollability (Cohen et al., 1983) , which can be effectively relieved by perceived social support (Budge et al., 2013; Dean & Lin, 1977; Heaney & Israel, 2008) . Another reason is that collective self-esteem could buffer against anxiety. Terror management theory has demonstrated that self-esteem plays an important role in relieving anxiety, which is confirmed by many studies (Burke et al., 2010; McFarlin & Blascovich, 1981; Rosenblatt et al., 1989; Sowislo & Orth, 2013) .Furthermore, based on this theory, many researchers have investigated the influence of collective self-esteem on anxiety, and results were consistent with the current study, indicating that collective self-esteem could also be effective in relieving anxiety (Gupta et al., 2014; Lam, 2007; Xie et al., 2008; Zhang, 2005) . Above all, the conception of "emotion-focused coping" suggested that reducing negative emotions such as anxiety is an effective way to reduce perceived stress (Lazarus & Folkman, 1984) . Also, evidence showed that lower anxiety was significantly associated with lower perceived stress (Bergdahl & Bergdahl, 2002; Hand et al., 2006; Lee, 2012; Sanzcarrillo et al., 2002) , which was further confirmed by our study.
Finally, collective self-esteem could reduce perceived stress through the chain mediation of perceived social support and anxiety, which is in line with our
hypothesis. An important function of perceived social support is to provide emotional comfort (House et al., 1988) , which can make us more optimistic (Thoits, 1995) .
Anxiety is usually caused by our pessimistic appraisal of our life (Beck, 1971; Folkman & Lazarus, 1985; Oatley & Johnsonlaird, 1987) , for which it can be effectively relieved by perceived social support. Moreover, the effect of chain mediation was stronger than the mediation of perceived social support, which reminds us the general public might perceive more emotional support from the country.
There are some limitations. First, 968 participants did not report their gender because of a program failure during data collection, for which we only analyzed the data with gender information again to control the potential influence of gender differences (N = 953, 291 males and 662 females). Results showed that the chain mediating effect (Effect = −0.02, Boot SE = 0.004, Boot 95%CI = [−0.024, −0.010]) was stable. Second, the current study mainly explored the influence of collective self-esteem on perceived stress. Future studies could carefully examine other types of self-esteem. Finally, the present study was a cross-sectional design that cannot confirm causality. Further research should adopt experimental or longitudinal designs to explore the causal assumptions in this study.
In all, the current study showed that collective self-esteem could reduce perceived Note. CSES = Collective Self-Esteem Scale; PSSS = Perceived social support scale; SAS = Self-Rating Anxiety Scale; PSS = Perceived stress scale; *** p < 0.001; ** p < 0.01; * p < 0.05 Note. Attention = Attention to COVID-19; CSES = Collective Self-Esteem Scale; PSSS = Perceived social support scale; SAS = Self-Rating Anxiety Scale; PSS = Perceived stress scale; *** P < 0.001; ** P < 0.01; * P < 0.05; The dependent variable in Models 1-3 was separately perceived social support, anxiety, and perceived stress. February 28: the WHO raised the global risk level for an outbreak to "very high".
March 10: all the 14 mobile cabin hospitals in Wuhan were closed.
February 12: the government intensifies checks for confirmed cases, adopts a "reception of new patients as much as possible" policy, and the number of confirmed cases peaks.