Examining the roles of depression, pain catastrophizing, and self-efficacy in quality of life changes following chronic pain treatment

Figures & data

Figure 1. The proposed moderated mediation model.

Table 1. Mean and SD for the study variables (N = 195) at baseline and 1-year follow-up.

	Baseline		Follow-up		Change scores
Variable	Mean	SD	Mean	SD	Mean	SD
Pain catastrophizing	15.30	5.13	12.15	6.31	−3.15***	5.64
Mental QOL	39.77	12.37	41.21	11.82	1.44	10.48
Physical QOL	30.91	9.63	33.19	9.82	2.28*	7.90
Depression	12.30	6.11	10.29	6.38	−2.01**	5.38
Pain self-efficacy	7.01	3.27	7.09	2.95	0.09	2.75

Note: *P < 0.05, **P < 0.01, ***P < 0.001 and indicates a significant difference between baseline and follow-up mean scores.

Table 2. Pearson correlation coefficients for the study variables (N = 195).

Variable	1	2	3	4	5	6	7
1. Baseline pain catastrophizing
2. Baseline physical QOL	−0.19**
3. Baseline mental QOL	−0.52***
4. Baseline depression	0.61***	−0.29***	−0.75***
5. Change in physical QOL	0.03	−0.39***	0.25***	−0.06
6. Change in mental QOL	0.21**	−0.01	−0.48***	0.32***
7. Change in depression	−0.20**	0.13	0.18**	−0.39***	−0.15*	−0.62***
8. Change in pain self-efficacy	0.10	−0.11	−0.18*	0.18*	0.18*	0.34***	−0.30***

Note: *P < 0.05, **P < 0.01, ***P < 0.001.

Figure 2. The moderation effect of the change in pain self-efficacy between baseline pain catastrophizing and change in depression. When pain self-efficacy decreased or was unchanged, there was no relationship between baseline pain catastrophizing and change in depression. However, there was a significant relationship between pain catastrophizing and the change in depression when pain self-efficacy increased. Patients with lower baseline pain catastrophizing had more severe (or worsening) depression after a year. Conversely, those with high baseline pain catastrophizing had decreased (or improved) depression after a year.