Fig. 1

The Models for psychological inflexibility, depressive symptoms, and sleep difficulty. For clarity, error terms for each indicator variable were omitted from the diagram. The upper values are the coefficients when the Patient Health Questionnaire-9 (PHQ) was used to measure depressive symptoms, and the bottom values are the coefficients when the 8-item PHQ was used to measure depressive symptoms. N = 663. ***p < .001; ** p < .01