Measurements

The demographic characteristics included in the questionnaire used in this study were as follows: age, sex, province, education level (undergraduate, graduate, doctoral, and postdoctoral), and school/vocational institution (universities, hospitals, research institutes and other research institutions).

PHQ-9 is a 9-item instrument used for evaluating depressive symptoms. Each item is scored from 0 (never) to 3 (almost all the time), with the total score ranging from 0 to 27. Higher scores imply more severe depressive symptoms. Usually, scores within the range of 0–4 are classified as presenting no obvious depressive symptoms, 5–9 indicate mild depression, 10–14 moderate depression, 15–19 severe depression, with scores ≥ 20 indicating very severe depression.³⁴ In this study, total scores < 5 were classified as indicating no symptoms of depression, ≥ 5 as indicating depression, with scores ≥ 1 in Item 9, “It is better to die or hurt oneself in some way”, indicating symptoms of self-injury or suicidal ideation.³⁵ The reliability and validity of the Chinese version of the scale has already been confirmed in previous studies.^36,37 Cronbach’s alpha for the internal consistency reliability ranged from 0.77 to 0.91 in the research of Sun et al.³⁶ While Wang et al demonstrated that the PHQ-9 scale correlated positively with the self-rating depression scale (r = 0.29, P < 0.001), with a cutoff score of 7 or higher on the PHQ-9 having a sensitivity of 0.86 and a specificity of 0.86.³⁷

GAD-7 consists of 7 items with each item scored at 4 levels ranging from 0 (never) to 3 (almost all the time). The total score ranges are from 0 to 21. Higher scores imply severe anxiety symptoms. Usually, total scores ≤ 4 are classified as indicating no anxiety, 5–9 as mild anxiety, 10–14 as moderate anxiety, and 15–21 as severe anxiety.³⁸ In this study, total scores < 5 were classified as indicating no anxiety and ≥ 5 as indicating symptoms of anxiety. Based on previous studies, the Chinese version of the scale has shown satisfying reliability (Cronbach’s alpha = 0.92³⁹) and validity (The Pearson correlation coefficient between GAD-7 and the anxiety subscale of the Hospital Anxiety and Depression scale scores was 0.66.⁴⁰ At the optimal cutoff value of 10, a sensitivity of 86.2% and a specificity of 95.5% were calculated.³⁸).

The original scale was compiled by Cohen et al in 1983.²⁸ In the present study, PSS-10 was used to measure perceived stress. This scale contains 10 items and includes two factors: Factor 1 (subjects’ perception of stress) is made up of negatively phrased items (items 1, 2, 3, 6, 9, 10); and Factor 2 (ability to cope with stress) is made up of positively phrased items (items 4, 5, 7, 8). The scale uses the Likert 5-point rating method with scores ranging from 0 (never) to 4 (always). Higher scores imply greater perceived pressure on the participants. The Chinese version has previously shown good reliability (Cronbach’s alpha = 0.81) according to the research of Sun et al.⁴¹ A previous study conducted by Wang has also shown that the PSS-10 is significantly correlated with both the Revised Beck Depression Inventory and the Beck Anxiety Inventory, indicating an acceptable degree of concurrent validity.⁴²

In the present study, the MBI-GS scale translated and revised by Li et al was used, with a total of 15 items covering three dimensions: emotional exhaustion (5 items), deindividuation (4 items), and low self-accomplishment (6 items).⁴³ Each item was scored from 0 (never) to 6 (daily), with 7 levels in total. The higher the score, the stronger the sense of job burnout. The reliability and validity of the Chinese version of the MBI-GS has been confirmed.⁴⁴ The internal consistency coefficients of emotional exhaustion, deindividuation, and low self-accomplishment were 0.925, 0.895 and, 0.920 respectively.⁴⁵ According to the research of Sun, the Corrected Item-Total Correlation values of items 1–6 in the dimension of low self-accomplishment are 0.757, 0.799, 0.838, 0.741, 0.795, and 0.82, respectively.⁴⁶ The deletion of any item will not significantly increase the reliability coefficient, so it can be reasonably concluded that the six items in the dimension of low self-accomplishment are reasonably set and the data are reliable. This study focused only on the dimension of low self-accomplishment.