Participants and procedure
A total of 330 medical students participated in the cross-sectional survey, and 306 (92.73%) of them answered all the questions. Out of the 306 participants, 115 (37.6%) were male and 191 (62.4%) were female, and their mean age was 23.24 years (SD = 1.35, range 18-27). In terms of professional distribution, 103 (33.7%) were practitioners of traditional Chinese medicine, 65 (21.2%) of clinical Chinese and Western medicine, 74 (24.2%) of rehabilitation therapy, and 64 (20.9%) of acupuncture and massage.
This study was conducted in affiliated hospitals of a provincial medical university. It deployed a pen-and-paper questionnaire to investigate the socio-demographic characteristics, empathy, self-esteem, and gratitude of medical interns. After signing the informed consent, participants were asked to complete a questionnaire in the classroom. The researcher and the trained graduate student of psychology were chosen as the experimenter, explaining the intention of the research to the students and emphasizing the principles of voluntariness, anonymity, and pragmatic answers. All questionnaires were recovered on the spot after completing the test. The Institutional Ethics Committee approved all the procedures.
Measures
Self-Esteem
Self-Esteem was measured according to the Self-Esteem Scale, or SES (Rosenberg, 1965). Out of ten items of the Scale, five adopt the reverse scoring method, each of them scored on a four-point scale ranging from 1 (very inconsistent) to 4 (very consistent). It includes items such as “I am satisfied with my life” and “In most ways my life is close to my ideal”. Scores may be anywhere from 10 to 40 points. The higher the scores are, the higher the level of self-esteem is. Scores below 25 points are grouped as low self-esteem, 26-32 moderate-level self-esteem, and over 33 high self-esteem [47]. The Chinese version of the Scale proves reliable and is widely used [48]. Cronbach’s alpha was tested 0.86 in the study.
Gratitude
Gratitude was measured according to the Gratitude Questionnaire-6, or GQ-6 [36]. Each of the six items included in the Questionnaire is scored on a seven-point scale ranging from 0 (completely disagree) to 6 (completely agree). It includes items such as “I feel thankful for what I have received in life” and “I sometimes feel grateful for the smallest things”. Scores may be anywhere from 6 to 42 points. The higher the scores are, the higher the level of gratitude is. The Chinese version of the Scale proves reliable [49]. Cronbach’s alpha was tested 0.76 in the paper.
Empathy
Empathy was measured according to the Chinese version of the Interpersonal Reactivity Index, or IRI-C, whose usage in the Chinese context has been proved reliable with adequate concurrent and construct validity by Zhang et al. [50]. The IRI-C is a 22-item self-report scale assessing individual empathy from four dimensions, namely, perspective-taking, fantasy, empathy concern, personal distress. The study used perspective-taking and empathy concern subscales, which contained 11 items. Each item is rated on a five-point scale ranging from 1 (very inconsistent) to 5 (very consistent). Five items adopt the reverse scoring method. The Index is compiled by Davis (1980) based on the multidimensional theory of empathy, a tool to measure the ability of empathy. The factor of perspective-taking is to measure the cognitive components, find out the tendency of individuals to understand, and see things from others' point of view in real life. The factor of empathy concern measures the emotional components and the degree of concern for others, warmth, and compassion. Therefore, the study adopts the perspective-taking subscale with the five items to measure cognitive empathy (e.g., “I sometimes try to understand my friends better by imagining how things look from their perspective.”). Scores range from 5 to 25, with higher scores indicating greater cognitive empathy. Affective empathy was measured by the empathy concern subscale with six items (e.g., “I often have tender, concerned feelings for people less fortunate than me.”). Scores of empathy concern subscales range from 6 to 30, with higher scores indicating greater affective empathy. Cronbach’s alpha of the perspective-taking subscale and the empathy concern subscale were 0.70 and 0.71 respectively, and the total Cronbach’s alpha was 0.74 in the study.
Data Analyses
Data analyses were conducted via SPSS 23.0 and Mplus 7.0. First, SPSS was used for data analyses, descriptive analyses, reliability tests, t-test, and correlation analyses for the whole sample. This study only used the self-report method to collect data, and there may be a common method bias (CMB) problem. In order to further improve the rigor of research, statistical analyses were carried out by Harman’s single factor test and the confirmatory factor analysis of the single-factor model.
Next, the Structural Equation Model (SEM) was deployed to examine the mediating role of gratitude in the relationship between self-esteem and empathy of medical college students during the pandemic of COVID-19. We used chi-square values to evaluate model fit, the Akaike information criterion (AIC), the Bayesian information criterion (BIC), the root-mean-square error of approximation (RMSEA), the Tucker Lewis index (TLI), the comparative fit index (CFI), the standardized root-mean-square residual (SRMR). A non-significant chi-square indicates a good model-data fit. General cutoffs for accepting a model are equal to, or greater than 0.90 for the CFI and TLI, and less than 0.08 for the SRMR and RMSEA.
Finally, we applied the SEM approach to assessing the following models: (a) a direct effect model with structural paths from self-esteem to cognitive empathy and affective empathy, and (b) an indirect effect model, with the gratitude inserted in between. The final model is presented in Figure 1.