Assessment of Depressive symptoms
Zung’s Self-Rating Depression Scale (SDS) was used [30]. The SDS also considered both emotional and physical symptoms, including 20 items, of which 10 were negative experiences and 10 were positive experiences. Add all the items together to form a rough score, which is multiplied by 1.25 and rounded to get the standard score to evaluate anxiety. The index score of 50 (original score=41) was set as the cut-off point for clinical significant depression in our study [32]. The Cronbach’s alpha of it was 0.921 in this study.