Results of the review
Twelve relevant studies were identified (614 patients, range 8 to 256), three of which had more than one intervention (giving 16 interventions overall). Seven studies had control groups. Five studies only made pre-treatment post-treatment comparisons.
Pooled effect sizes at post-treatment: The pooled meta-analysis showed that participants who received cognitive and behavioural treatment had a significantly lower level of pain than the comparison groups (pre-treatment or control groups) for all 16 comparisons (z score 0.47, 95% CI 0.34 to 0.60). The pooled effect size for medication use for seven comparisons at post treatment was not significant; and neither was that for depression for seven comparisons. The pooled effect size for eight comparisons showed that cognitive and behavioural treatment had a significant, but very small, positive benefit for physical functioning (z score 0.15, 95% CI 0.01 to 0.30).
Pooled effect sizes at follow-up: The pooled meta-analysis at follow-up (mean 9.2 months) showed that participants who received cognitive and behavioural treatment had a significantly lower level of pain than the comparison groups (for ten comparisons) at follow-up (z score 0.56, 95% CI 0.41 to 0.71). The pooled effect size (for seven comparisons) showed that cognitive and behavioural treatment had a significant but small positive benefit for physical functioning (z score 0.21, 95% CI 0.05 to 0.37). Pooled analyses were not performed for depression or medication use at follow-up as insufficient results for individual interventions were available.