Manual-therapy randomized controlled trials (RCTs) are difficult to perform because it's challenging to conceal a placebo when patients are able to physically feel a treatment that's being delivered. Now, though, researchers have successfully completed the first manual-therapy RCT with a documented successful blinding. The three-armed trial evaluated the efficacy of chiropractic spinal manipulative therapy (CSMT) in the treatment of migraine versus placebo (sham chiropractic) and control (usual drug treatment).
Migraine days were significantly reduced within all three groups from baseline to post-treatment; the effect continued in the CSMT and placebo groups at all follow-up time points, whereas the control group returned to baseline. The effect of CSMT was likely due to a placebo response.