On January 30th, 2020, the World Health Organization (WHO) announced a notice that the COVID-19 epidemic had been accounted for a public health emergency which aroused international concern (World Health Organization, 2019). Its characteristics such as highly infectious and rapid transmission had posed a threat to people's health, both physically and mentally. Faced with the infection which had become more and more serious, there were some countermeasures adopted by the Chinese government in order to control population flow and reduce infection, for instance, home quarantine and postponing the start of school year (Wang H. et al., 2020). However, due to the sudden long-term isolation, the reduction of social interaction and the change of learning style, college students might experience maladjustment, anxiety and other negative emotions. Students often experienced academic anxiety in learning situations (Collie et al., 2017; Lee, 2020). Some studies had shown that, compared to the ordinary college students, the medical students had a higher level of anxiety and depression under the impact of the epidemic of COVID-19 (Wang H. et al., 2020; Wang K. et al., 2020). At the same time, the level of anxiety in daily life and work continued to rise as the pandemic spread (Rodriguez et al., 2020). With the longer time of social isolation, people's anxiety and depression symptoms would become more prominent (Knopf, 2020). Indeed, academic anxiety had been proved to be significantly correlated with academic engagement and disengagement (Martin, 2008; Martin et al., 2012). Therefore, making a thorough inquiry of the academic anxiety level of medical students in time of COVID-19 epidemic and its psychological mechanism could provide evidence for future intervention.

Self-handicapping was the process of creating barriers to achieving successful performance designed to safeguard individuals' sense of self- competence (Jones and Berglas, 1978). The phenomenon that self-handicapping had a positive correlation with test anxiety was discovered in a qualitative study, and it was more likely that people with high self- handicapping were more likely to seek pretext for their procrastination, abandonment or failure (Martin et al., 2003). In other words, people with high self-handicapping had higher pressure before the exam, but they would not work very hard, so the final score was poorer than others (McCrea and Hirt, 2009). As mentioned above, people with high self-handicapping might procrastinate, deliberately lose learning materials, strategically give up efforts or avoid practicing skills in advance, which led to a decline in their academic performance (Martin, 2011; Putwain, 2019). As a major barrier to realizing personal potential and achievement, self-handicapping had many negative connections with physical and mental health and academic life (Barutçu and Demir, 2020). In time of the COVID-19 outbreak, applying the strategies of self-handicapping was one of the important factors affecting the physical and mental health development of medical students, which might lead to negative effects, such as poor learning status and lack of effort (Zarshenas et al., 2019). Therefore, for the purpose of enabling students to have a higher level of mental health and better academic performance during the COVID-19 epidemic, exploring their self-handicapping behaviors was worthwhile.

The emergence of the COVID-19 epidemic might aggravate symptoms such as academic anxiety and self-handicapping. Previous studies have explored the direct relationship between the academic anxiety and self-handicapping (Martin et al., 2003; McCrea and Hirt, 2009). However, it was still unclear about the potential mediating mechanism or moderating mechanism of academic anxiety affecting self-handicapping. In order to fill in these gaps, this study constructed a four-variable theoretical model to test whether and how the self-handicapping of Chinese medical students was affected by academic anxiety, procrastination, and hardiness. The way and time academic anxiety could affect self-handicapping would be advanced by the findings, and how to get rid of the negative influence of academic anxiety in time of the COVID-19 epidemic would also be known.

This paper analyzed the mechanisms underlying the association between academic anxiety and self-handicapping by constructing a moderated mediation model among medical students in time of the COVID-19 epidemic. This study found that, in the relationship between academic anxiety and self-handicapping, procrastination played a mediating role, and that hardiness played a moderating role. Furthermore, hardiness also moderated the mediating effect of procrastination. Taking into account the negative effects of academic anxiety and self-handicapping, more attention should be paid to the psychological conditions of medical students in time of the COVID-19 epidemic, so as to intervene in self-handicapping by cultivating hardiness in an appropriate way.

Firstly, our study found that self-handicapping would be significantly predicted by academic anxiety among medical students. Our research result was consistent with the result of previous studies which reported that academic anxiety had a positive association with self-handicapping (Thomas and Gadbois, 2007). In addition, because students were affected by isolation in time of the COVID-19 epidemic, they could only learn via the Internet to replace ordinary face-to-face courses in the classroom. Therefore, teachers could not give immediate feedback on students' learning. Due to the changes in the study, students underwent academic anxiety as the result of their fear toward failure. The self-worth theory (Covington, 1992) suggested that students' self-worth could be affected by failure, because failure was considered a symbol of low ability, which was considered the same as low self-worth (Martin et al., 2001). In the present educational environment, the emphasis on individual achievement and performance, as well as perceptions of self-worth, was heightened (Leondari and Gonida, 2007; Gadbois and Sturgeon, 2011). Consequently, students whose level of academic anxiety was higher were willing to adopt self-handicapping and strategies of defensive pessimistic, which could protect their sense of self-worth from expected failure by reflecting the attribution away from their perceived incompetence (Covington, 2009; Putwain, 2019). Although some of the previous studies have indicated that positive outcomes such as improving performance and enjoyment, minimizing the impact of failure, and preparing people for others' evaluations in case that they might fail would be provided by self-handicapping (Rhodewalt and Hill, 1995; Deppe and Harackiewicz, 1996; Brown and Kimble, 2009), Martin et al. (2001) study showed that, compared with defensive and pessimistic strategies, self-handicapping had a higher degree of negative correlation with educational outcomes (Thomas and Gadbois, 2007). Therefore, high learning anxiety not only led to students' self-handicapping, but also caused students' poor academic performance.

Secondly, the results confirmed that the relationship between academic anxiety and self-handicapping would be partially mediated by procrastination. Studies in the past have revealed that there was a significant connection between procrastination, academic anxiety and self-handicapping (Akin, 2012; Yerdelen et al., 2016), but as far as we know, there was no research which had proved the indirect relationship between academic anxiety and self-handicapping through the mediating effect of procrastination. Our research suggested that academic anxiety had an influence on procrastination, and procrastination mediated the impact of academic anxiety on self-handicapping to a certain extent, and this finding was in consistency with our previous hypothesis. In addition, long-term online learning would increase the time students spend on the Internet, and a high degree of Internet dependence might have negative effects on college students, such as causing anxiety (Lai et al., 2015), social isolation (Shaw and Black, 2008), a decrease in self-confidence (Steel, 2007), and even Internet addiction (Hayat et al., 2020). Research in the past had recognized barriers to online learning environments, such as issues of self-regulation, self-pacing, learning speed, and differences in effort (Azevedo et al., 2005; Hooshyar et al., 2019). Therefore, in time of the quarantine, students were still unable to compare their own learning progress with others and their fear and anxiety increased as a result, which would cause academic procrastination.

Furthermore, the results of this investigation showed that hardiness could moderate both the effect that academic anxiety itself exerted on self- handicapping and the effect that academic anxiety exerted on self- handicapping through procrastination. The direct effect of medical students who had low hardness was stronger, and the indirect effect of medical students with both high and low hardness was stronger. That is, hardiness not only reduced the direct influence of academic anxiety on self- handicapping, but also remitted the indirect influence of academic anxiety on self-handicapping via procrastination. These findings were consistent with research in the past revealing the protective effects of academic anxiety and self-efficacy on hardiness (Abdollahi and Noltemeyer, 2018; Abdollahi et al., 2018; Cheng et al., 2019).

To be more specific, the academic hardiness theory (Benishek et al., 2005) held that medical students who had high levels of academic hardiness had less procrastination. They believed it was a chance for growth and development, rather than a stressful event for students to learn online in time of the COVID-19 epidemic. Furthermore, they were confident and able to continue to study hard and pursue academic goals (Abdollahi et al., 2018). There were an internal locus of control, effective learning strategies, time management skills, achievement orientation, and low levels of academic stress within the students who had high academic hardiness (Abdollahi et al., 2020a,b). This kind of students were unlikely to avoid academic tasks by adopting procrastination or self-handicapping strategies. In time of the COVID-19 epidemic, facing a harsh academic environment, students with high academic hardiness tended to assess this situation as more challenging, controllable and less threatening, and they were easier to adapt and participate in situations to learn more and thrive even under pressure (Kamtsios and Karagiannopoulou, 2015). Students who had high academic hardiness also used more emotional self-regulation skills, which could help them optimistically and actively participate in academic tasks, and challenged their arduous courses to gain experience under pressure (Abdollahi et al., 2015). Therefore, medical students with high hardiness could better deal with academic anxiety.

There were a few limitations in this study, which demanded to be improved in consecutive research. Firstly, the study used a cross-sectional study design; therefore, no causal explanation could be obtained. Consecutive research should use longitudinal design or experimental research to explore the causal relationship between academic anxiety and self-handicapping by using cross design, multi-layer linear model or by manipulating the independent variables and mediating variables. Secondly, we used the self-report questionnaires to explore the role of academic anxiety, procrastination, and hardiness. Consecutive research should conduct interventions for students and their families. Thirdly, the participants in this study came from Fujian Province of China. Fujian Province is a low-risk area for COVID-19. Moreover, this study did not collect data right before the final exam. Thus, the response of medical students might be affected by the time and place of data collection. Finally, this research only assessed procrastination as a mediating factor and hardiness as a moderating factor. Thus, consecutive studies are demanded to assess other potential factors to improve its robustness. Future research can aim to address these limitations.

Although this study had some limitations, it was the first study to investigate academic anxiety and self-handicapping of medical students in time of the COVID-19 epidemic, and it also explored the mediating role of procrastination and the moderating role of hardiness. The exploration of the underlying mechanism of this relationship would enrich the existing research results. In particular, this study explained how and when academic anxiety affected self-handicapping, and how procrastination impacted self-handicapping. In addition, there were some important practical implications. First, parents and educators must be aware of the academic anxiety of medical students in time of the COVID-19 epidemic and its negative effects in order to help them reduce their academic anxiety over time. Second, given that procrastination was a significant mechanism linking academic anxiety and self-handicapping, it should be effective for educators and psychologists to help medical students to develop good study habits to reduce the behavior of procrastination. And if we could combine psychoeducational, behavioral, and cognitive interventions, a positive effect could be achieved (Van Eerde and Klingsieck, 2018; Malouff and Schutte, 2019). For instance, some studies have suggested that the way to meddle in medical students' procrastination through the internet-based acceptance and commitment therapy and cognitive behavioral therapy which were effective and acceptable (Gagnon et al., 2019; Küchler et al., 2019). Besides, the need to develop specific support plans for medical students' procrastination behavior was emphasized, including improving academic skills, increasing self-regulated learning strategies, and reducing emotional state problems (Hen, 2018). Thirdly, the direct influence of academic anxiety on self-handicapping could be alleviated by hardiness, but the indirect influence of academic anxiety on self- handicapping through the mediating role of hardiness could also be alleviated by hardiness. Children's tough personality could be affected by parental education styles (Higinio and Antonia, 2020). Moreover, previous studies had suggested that the hardiness of nurses, as a positive personal resource, could reduce nurses' stress and burnout, influenced the way nurses interacted with the working environment, and improved nurses' input (Bemana et al., 2014; Garrosa et al., 2014). Thus, to improve medical students' hardiness might be a good method for buffering the negative impacts of academic anxiety.

The association between academic anxiety and self-handicapping was partially mediated by the level of procrastination of medical students during the COVID-19 pandemic. In addition, hardiness not only moderated the effect of academic anxiety on self-handicapping of medical students, but also moderated the mediating effect of procrastination. Specifically, it moderated the effect of procrastination on self-handicapping. As academic anxiety and self-handicapping had a negative impact on medical students, it was necessary to pay close attention to their physical and mental conditions, and appropriate intervention could be taken with the self- handicapping of medical students by cultivating hardiness.

The original contributions presented in the study are included in the article/Supplementary Material, further inquiries can be directed to the corresponding author/s.

The studies involving human participants were reviewed and approved by Biomedical Research Ethics Committee of Fujian Medical University (No. 79). The patients/participants provided their written informed consent to participate in this study.

The idea for this study was conceived by QJ, JJ, and BZ. QJ and JX collected data. JJ made an analysis and interpretation of the data. JJ and LW wrote the manuscript. QJ revised the manuscript. The final version was read and approved by all authors.

This study was supported by School of Health of Fujian Medical University, Research topics of Ideological and Political Work of Fujian Medical University (70000049).

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

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