Differences in outcome of a multidisciplinary treatment between subgroups of chronic low back pain patients defined using two multiaxial assessment instruments: the Multidimensional Pain Inventory and lumbar dynamometry

OBJECTIVE: To investigate the effects of a multidisciplinary back school programme (Roessingh Back Rehabilitation Programme, RRP) compared with usual care, as well as differences in treatment outcome between subgroups defined using two multiaxial assessment instruments: the Multidimensional Pain Inventory (MPI-DLV) and lumbar dynamometry. DESIGN: Randomized controlled trial. SETTING: Rehabilitation. SUBJECTS: One hundred and sixty-three patients with chronic, aspecific low back pain. INTERVENTION: All subjects were randomly assigned either to a multidisciplinary, physically oriented group treatment or to their usual care. MAIN OUTCOME MEASURES: The Roland Disability Questionnaire and health-related quality of life (EuroQol, EQ5-D) were measured as primary outcomes before randomization and after eight weeks and six months follow-up. RESULT: Only 30-50% of the patients in the RRP group showed improvement and this number is not significantly different from the control group. Subgroup analyses give some first indications that multiaxial measurement instruments can be used to identify subgroups with differences in treatment effects. CONCLUSION: The overall effect of a multidisciplinary treatment is disappointing, however multiaxial assessment before admission might be valuable in clinical practice, resulting in more effective treatments for patients with chronic low back pain.