Chiropractic spinal manipulation: what does the ‘best’ evidence show?

Abstract Background The evidence of effectiveness of chiropractic is controversial. Objectives To summarise all Cochrane reviews of chiropractic spinal manipulation. Methods The Cochrane database was searched for all Cochrane reviews of chiropractic manipulation. Cochrane reviews with the terms ‘chiropractic’, ‘manipulation’ or ‘manual therapy’ in the title, abstract or keywords were considered. Protocols of reviews were excluded, as were studies that did not focus specifically on chiropractic spinal manipulation. Data extraction was performed by the author according to predefined criteria. Results Five Cochrane reviews were eligible for inclusion. Due to clinical and statistical heterogeneity, a meta‐analysis was not possible and the findings of the reviews were discussed narratively. The five reviews related to the following conditions: low back pain, asthma, dysmenorrhoea and neck pain. Each review included between three and 39 primary studies. Cautiously positive conclusions emerged for low back pain and neck pain. For the two non‐spinal conditions, the conclusions were negative. Conclusions Cochrane reviews, generally considered to be the most reliable evidence, provide limited evidence that chiropractic may be effective for low back and neck pain, but failed to support the use of chiropractic for non‐spinal conditions.