In April 2022, we adopted the cluster convenience sampling method to study the medical staff from four hospitals on the Zhejiang Province medical team that was sent to assist Shanghai. According to the particularity of the epidemic prevention and control work, with the active cooperation of all units, the survey subjects are trained in a unified way through tactical meetings before the start of the research investigation to ensure the authenticity, accuracy, and standardization of the data. An anonymous cross-sectional population-based online survey was conducted via the WeChat-incorporated Wen–Juan–Xing platform (Changsha Ranxing Information Technology Co., Ltd., Hunan, China). The questions raised in the completion process were answered in a timely manner, and anonymous responses were returned after completion. This study was approved by the Taizhou Hospital Committee of Zhejiang Province (K20220402).

The self-designed general information questionnaire included items for gender, age, length of service and experience, education, professional title, marital status, family members' status, personnel relations, work experience in emergencies, severe, infection, respiratory and other critical diseases in the early stage of providing aid in Shanghai, experience in participating in epidemic prevention in the past 3 years, and participation in nucleic acid collection in the past 3 months.

Zung's Self-rating Anxiety Scale (SAS): SAS was developed by William W.K. Zung in 1971 (Dunstan and Scott 2020). This scale contains 20 items, including 15 positive scores and five negative scores. Each question is scored ranging from 1 (none or few times) to 4 (most or all times). A cut-off score above 45 points indicates anxiety (Zung 1971). The higher the SAS score, the more obvious the anxiety tendency of the patients. This study's total postanalysis Cronbach's alpha coefficient was 0.931 (Dunstan and Scott 2020).

The Psychological Resilience Scale (CD-RISC): the CD-RISC was developed by American psychologists Connor and Davidson in 2003. This scale comprises 25 items over three metrics (tenacity, strength, and optimism) that assess resilience or capacity to change and to cope with adversity. The Likert 5-level scoring is adopted, and the scoring range of each item is from 0 to 4 points: 0 for completely incorrect scoring, 1 for rarely correct scoring, 2 for sometimes correct scoring, 3 for usually correct scoring, and 4 for almost all times. The total score ranges from 0 to 100. A higher score indicates better resilience. This study's total postanalysis Cronbach's alpha coefficient was 0.912, which indicated good reliability and validity for clinical practice (Kuiper et al. 2019).

Multidimensional Scale of Perceived Social Support (MSPSS): the MSPSS, developed by Zimet et al., modified by Jiang Qianjin, evaluates the respondents’ perceived level of support that they received from their social network. This tool comprises 12 items that assess social support from family, friends, and significant others. Participants used a seven-point Likert response format (1 = ‘very strongly disagree’ to 7 = ‘very strongly agree’) to rate these items. The total scores range from 12 to 84, with higher scores indicating greater total perceived social support from all three sources. The total postanalysis Cronbach’s alpha coefficient of the MSPSS in this study was 0.953 (Pushkarev et al. 2020).

Simple coping style questionnaire (SCSQ): the questionnaire was prepared by Xie Yaning in 1998. The simple coping style questionnaire consists of two dimensions (subscale), positive coping and negative coping, including 20 items, which can effectively reflect the possible coping tendencies when people are stimulated by external stimuli (Shigemura et al. 2020). The scale scores "0/1/2/3" corresponded to "not/occasionally/sometimes/often". The positive response dimension consists of items 1–12, which mainly reflect the characteristics of positive response. The negative coping dimension consists of items 13–20, which mainly reflect the characteristics of negative coping. This study will also adopt the positive response part of this questionnaire. The postanalysis Cronbach’s alpha coefficient of positive coping dimensions in this study was 0.880.

This study utilized SPSS 22.0 software for data analysis. Data are described by the number of cases and percentage (%), and the chi-square (X2) test was used for comparisons between groups. The measurement data conforming to the normal distribution were described by the mean with standard deviation, and the comparison between the two groups was performed with a t test. Pearson’s correlation analysis was used to analyse the correlation between coping style and anxiety, psychological resilience, and social support. Stepwise multiple linear regression analysis was used to explore the influencing factors of coping styles. P < 0.05 indicates statistical significance.