title: Spinal Manipulation Vs Sham Manipulation for Nonspecific Low Back Pain: A Systematic Review and Meta-analysis.
abstract: OBJECTIVE
  The purpose of this systematic review was to identify and critically evaluate randomized controlled trials of spinal manipulation (SM) vs sham manipulation in the treatment of nonspecific low back pain.
  
  
  METHODS
  Four electronic databases were searched from their inception to March 2015 to identify all relevant trials. Reference lists of retrieved articles were hand-searched. All data were extracted by 2 independent reviewers, and risk of bias was assessed using the Cochrane Back Review Group Risk of Bias tool.
  
  
  RESULTS
  Nine randomized controlled trials were included in the systematic review, and 4 were found to be eligible for inclusion in a meta-analysis. Participants in the SM group had improved symptoms compared with participants receiving sham treatment (standardized mean difference = - 0.36; 95% confidence interval, - 0.59 to - 0.12). The majority of studies were of low risk of bias; however, several of the studies were small, the practitioner could not be blinded, and some studies did not conduct intention-to-treat analysis and had a high level of dropouts.
  
  
  CONCLUSIONS
  There is some evidence that SM has specific treatment effects and is more effective at reducing nonspecific low back pain when compared with an effective sham intervention. However, given the small number of studies included in this analysis, we should be cautious of making strong inferences based on these results.
authors.affiliation: Private Practice, Align Body Clinic, Bath, UK.
authors.forename: Jay K
authors.initials: JK
authors.lastname: Ruddock
authors.affiliation: MRC Integrative Epidemiology Unit, School of Social and Community Medicine, University of Bristol, Bristol, UK; Centre for Academic Mental Health, School of Social and Community Medicine University of Bristol, Bristol, Bristol, UK.
authors.forename: Hannah
authors.initials: H
authors.lastname: Sallis
authors.affiliation: The NIHR Biomedical Research Unit in Nutrition, Diet and Lifestyle at the University Hospitals Bristol NHS Foundation Trust and University of Bristol, Bristol, UK.
authors.forename: Andy
authors.initials: A
authors.lastname: Ness
authors.affiliation: The NIHR Biomedical Research Unit in Nutrition, Diet and Lifestyle at the University Hospitals Bristol NHS Foundation Trust and University of Bristol, Bristol, UK.
authors.forename: Rachel E
authors.initials: RE
authors.lastname: Perry
keywords: Low back pain; Manipulation; Placebo; Review of the literature; Spinal