Effects of behavioural exercise therapy on the effectiveness of multidisciplinary rehabilitation for chronic non-specific low back pain: a randomised controlled trial

BACKGROUND: The long-term effects of behavioural medical rehabilitation (BMR), as a type of multidisciplinary rehabilitation, in the treatment of chronic non-specific low back pain (CLBP) have been shown. However, the specific effects of behavioural exercise therapy (BET) compared to standard exercise therapy (SET) within BMR are not well understood. The aim of the study was to assess the effectiveness of BMR + BET compared to BMR + SET in individuals with CLBP in a two-armed, pre-registered, multicentre, parallel, randomised controlled trial (RCT). METHODS: A total of 351 adults with CLBP in two rehabilitation centres were online randomised based on an ‘urn randomisation’ algorithm to either BMR + SET (n = 175) or BMR + BET (n = 176). Participants in both study groups were non-blinded and received BMR, consisting of an multidisciplinary admission, a psychosocial assessment, multidisciplinary case management, psychological treatment, health education and social counselling. The intervention group (BMR + BET) received a manualised, biopsychosocial BET within BMR. The aim of BET was to develop self-management strategies in coping with CLBP. The control group (BMR + SET) received biomedical SET within BMR with the aim to improve mainly physical fitness. Therapists in both study groups were not blinded. The BMR lasted on average 27 days, and both exercise programmes had a mean duration of 26 h. The primary outcome was functional ability at 12 months. Secondary outcomes were e.g. pain, avoidance-endurance, pain management and physical activity. The analysis was by intention-to-treat, blinded to the study group, and used a linear mixed model. RESULTS: There were no between-group differences observed in function at the end of the BMR (mean difference, 0.08; 95% CI − 2.82 to 2.99; p = 0.955), at 6 months (mean difference, − 1.80; 95% CI; − 5.57 to 1.97; p = 0.349) and at 12 months (mean difference, − 1.33; 95% CI − 5.57 to 2.92; p = 0.540). Both study groups improved in the primary outcome and most secondary outcomes at 12 months with small to medium effect sizes. CONCLUSION: BMR + BET was not more effective in improving function and other secondary outcomes in individuals with CLBP compared to BMR + SET. TRIAL REGISTRATION: Current controlled trials NCT01666639, 16/08/2012. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12891-021-04353-y.