Methodological quality of randomized clinical trials on treatment efficacy in low back pain

This was a review of criteria-based meta-analyses.

To assess the methodological quality of published randomized clinical trials on the efficacy of commonly used interventions in low back pain.

During the last several decades, the number of published randomized clinical trials regarding low back pain has continued to grow. For some interventions, considerable numbers of trials are available. Trials have been shown to vary substantially regarding their quality.

A computer-aided search was conducted of published randomized clinical trials into the efficacy of spinal manipulation and mobilization, exercise therapy, back schools, bed rest, orthoses, and traction therapy. There was additional screening of journals not covered by Medline and Embase. The methodological quality of the studies was assessed using a set of predefined criteria.

Sixty-nine different randomized clinical trials were identified. Methodological scores varied between 16 and 82 points (maximum was 100 points). Methodological quality tended to be associated with the outcomes of the studies. Methodological shortcomings were frequently found--e.g., small sample sizes, no description of the randomization procedure, no description of drop-outs, no placebo-control group, and lack of blinded outcome assessments.

Although a considerable number of randomized clinical trials have been carried out to evaluate the efficacy of interventions in low back pain, their methodological quality appears to be disappointingly low. Future trials are clearly needed, but much more attention should be paid to the methods of such studies.