2.4.1. Symptom checklist-90(SCL-90)

The SCL-90 was originally developed by Derogatis In 1984.^[7] Yu et al translated it into Chinese.^[8] SCL-90 is used to assess individual psychological symptoms. It comprises 90 items, and includes 9 subscales (somatization, obsessive–compulsive, interpersonal sensitivity, depression, anxiety, hostility, phobic anxiety, paranoid ideation, and psychoticism). It uses a 5-point scale (1 = “no problem” to 5 = “very serious”). Higher scores indicate profound psychological distress. When the total SCL-90 score is > 160 or a subscale score is > 2, it was judged that the participant has abnormal psychological performance. The validity coefficient of various symptoms is between 0.77 and 0.99.