Table 2.

Effect of intervention at 1-year follow-up (unmatched)

Outcome measure	Adjusted estimate	P value	95% CI	Relative difference with intervention
EQ-5D summary scores
Health utility score	0.12	0.01	0.04 to 0.20	7.5 %
EQ-5D VAS	11.88	<0.001	5.91 to 17.86	11.9 %
Generalised self-efficacy	2.32	0.02	0.32 to 4.31	7.7 %
Brief Pain Inventory Scores
Summary (mean) pain score (across BPI)	−0.62	0.09	−1.35 to 0.11	6.2 %
Average pain score (single question)	−0.75	0.05	−1.50 to 0.00	7.5 %
Worst pain score (single question)	−0.59	0.16	−1.41 to 0.23	5.9%
Pain interference with enjoyment of life (single question)	−1.00	0.03	−1.89 to −0.11	10.0 %
Pain interference on normal work (single question)	−0.69	0.16	−1.66 to 0.28	6.9%
Mean pain interference summary	−0.73	0.07	−1.52 to 0.06	7.3%
Hospital anxiety and depression (HADS) ORs
HADS depression	0.38	0.01	0.19 to 0.76	62 %
HADS anxiety	0.58	0.11	0.30 to 1.13	43 %

Effect of the intervention on quality-of-life outcome measures compared with usual care at 1-year follow-up. Linear regression models with absolute effects and scaled relative effects for: (1) EQ-5D, EuroQol five-dimension health state; (2) EQ-VAS: EuroQol Visual Analogue Scale; (3) Generalised self efficacy (GSE); (4) Summary (mean of all) pain scores: mean of four scores from brief pain inventory; (5) ‘average pain’; (6) ‘worst pain’; (7) ‘least pain’; (8) ‘pain right now’. All pain scores ranges=0–10. Logistic regression, with ORs for risk of screening for depression (HADS-depression ≥8/21) and anxiety (HADS-anxiety ≥8/21).

BPI, Brief Pain Inventory; HADS, Hospital Anxiety and Depression Scale; VAS, Visual Analogue Scale.