A 2011 Cochrane review concluded that spinal manipulative therapy (SMT) is no better than other interventions for reducing pain and improving function in chronic low back pain (CLBP). Using individual participant data (IPD) from trials has advantages, among others: a more precise estimate of the effect and the potential to identify moderators. Our objective was to assess the effect of SMT in adults with CLBP and to identify relevant moderators. All trials from the 2011 Cochrane review were included in this IPD. We updated the search (April 2016) IPD from eligible studies was requested. Primary outcomes were pain intensity (VAS/NRS) and back-specific function (RMDQ). Risk of bias was assessed. For the treatment effect, an one-stage approach (mixed model technique, intention-to-treat principle) was used; a second-stage approach was conducted as confirmation. For the moderator analyses, one-stage approach was conducted for 19 variables.Purpose of the study and background
Methods