Symptom distressThe Physical Symptom Distress Scale (PSDS; Niu, 2002) was used to measure symptom distress. The original PSDS consisted of 32 items. Tishelamn et al. (2000) sug-gested adding symptom frequency. Therefore, both symp-tom severity and symptom frequency were included in the current study. Symptom severity was measured using a four-point Likert scale (0 = ‘none’ to 3 = ‘severe’). Symptom frequency was measured using a five-point Likert scale (0 = ‘none’ to 4 = ‘almost every day’). The symptom distress was calculated by the symptom severity score multiplied the symptom frequency score. The range for final total PSDS scores was 0 to 384 (32 3 4 = 384). Cronbach’s alpha