**4. Discussion**

The abrupt spread of the COVID-19 pandemic worldwide and the declaration of the disease as a Public Health Emergency of International Concern were bad omens for public health. Healthcare providers and health science students were always at high risk of infectious diseases and, conclusively, their knowledge of and their attitudes toward the new virus are of major importance for future interventions and health policy planning.

According to our knowledge, this is the first study to develop a tool with these dimensions investigating Greek nursing students' views during the COVID-19 confinement. In this study, which was conducted one month after the announcement of lockdown in Greece, the researchers attempted to investigate COVID-19-related knowledge, the attitude toward this new situation, the level of adherence towards the restriction measures, and volunteerism among nursing students. The developed instrument was comprehensively tested and showed satisfactory psychometrical properties, and it can be used as a valid research tool in future studies in this field. The instrument accounted for 50% of the total variance, indicating that the four factors model was statistically appropriate, including COVID-19 knowledge, attitudes toward restriction measures, compliance with restriction measures, and volunteering. Regarding the dimension of COVID-19 knowledge, we conclude that knowledge is an essential issue, as has been confirmed by several studies [21–24]. Increased awareness and promotion of positive attitudes among students are imperative to changing students' health practices and improving compliance with preventive measures. Positive attitudes and compliance with restriction measures could significantly improve the public's preventive health behaviors and the preparedness for COVID-19 [21–23,25,26]. Finally, a relatively new issue emerged from our factor analysis: the factor "volunteering". Health care students internationally volunteered to assist in hospitals due to the COVID-19 pandemic, providing crucial aid to hospital functioning and patients' care in healthcare systems [27,28].

One of the main results of this study was the students' high knowledge levels (mean = 4.22), as well as their preference to get informed by official organizations and official electronic databases compared with social media. Recent studies show the importance of the need for health science students to be well-informed regarding the symptoms of COVID-19 and prevention strategies [17]. Further, a study in Turkey regarding nursing students revealed that almost half of the respondents (48%) were well-informed about the coronavirus disease, despite the fact that knowledge was associated with an increase in their stress levels [29]. Furthermore, a study based on medical and health students in India found a lack of availability of credible knowledge, with the majority (65.17%) getting informed through social media, and a small percentage of them (11.47%) not informed regarding the pandemic [19]. Notably, there is evidence indicating that health science students have higher levels of knowledge compared with social science students [30], and also have an obligation to adopt true knowledge and disseminate valid evidence regarding the spread of the virus [17].

Literature highlights the need for students' attention to the value of the knowledge refinement process and evidence-based answers through critical appraisal of the information before applying or sharing it [31]. At the same time, authors in cooperation with public health organizations and WHO suggest frameworks, strategic partnerships, and coordinated actions for infodemic management, involving health professionals, students, researchers, and stakeholders [32–34]. As a further step, researchers claim that virus-related knowledge and health literacy are needed in order to achieve higher levels of compliance with restriction measures to control citizens' fear, resist the infodemic, and to promote citizens' trust in reliable information and recommendations [15].

Moreover, in this study, most of the participants hold a positive attitude toward restriction measures. Similarly, a national study in the United Kingdom conducted among final year medical students showed that the majority (93.6%) believed that the measures during the pandemic are necessary [35]. In contrast, in the US, 37.8% of the students presented unwillingness to comply with restriction measures, while in Cyprus, researchers showed that women and individuals over the age of 30 were more likely to implement the measures [36,37].

Additionally, the present study reveals the intentions of students to volunteer in clinical settings. This is in line with previous studies' findings in Spain, which found that a high percentage of students expressed the desire to assist nurses in providing patient care during the pandemic [38]. Internationally, nursing and medical students were willing to volunteer for certain tasks in order to assist the healthcare system and support the COVID-19 response effort [39]. Volunteerism in the period of the COVID-19 crisis, although can cause uncertainty and fear for students acting in the frontlines, is still considered a valuable lesson for their future interprofessional practice, and therefore, a high percentage of students report a willingness to get involved [28,35].

Moreover, students reported that the COVID-19 pandemic could change people's lives in a significant way, which is in line with previous findings. Similarly, a study conducted in Hong Kong showed that the vast majority of participants (97%) were worried about COVID-19 and its impact on their daily routines [40], while another study conducted in the United Kingdom reported medical students' disappointment due to the worldwide travel restriction [35].

In the present study, a portion of the participants alleged that the quarantine measures could have a moderate effect on their health (mean = 2.46). Rawls and Gibson stated that the pandemic may cause negative economic, psychological, and cultural consequences [41], as this situation affects students' psychological status and creates anxiety and fears for their future careers [38,42]. In addition, there is evidence linking social isolation with uncertainty, insecurity, and instability to students, as well as with emotional difficulties during student life [36]. Generally speaking, studies have shown that the COVID-19 pandemic and measures to control it have a great impact on individuals' quality of life and mental health, while in a study conducted in the general population of Cyprus, the psychological morbidity was associated with being a university student [42].

The present study has some strengths, as well as limitations. A possible limitation of our study is its cross-sectional study design, which does not allow us to assess possible changes in nursing students' attitudes, their levels of knowledge, or their adherence to restrictions over the different stages of the COVID-19 pandemic. On the other hand, the cross-sectional design allows researchers to use real-time data and clearly depicts the participants' knowledge and attitudes at that point in time, during the confinement. It is worth noting that to our knowledge, this is the first study to develop and validate a tool to assess nursing students' knowledge and attitudes toward COVID-19 in a university environment during the period of quarantine. Another limitation is that we did not perform a confirmatory factor analysis since we did not have a prior theory regarding the number and the structure of the factors. Thus, there is a need for further studies in this field to confirm and expand our findings.
