Vickers et al. 2018, Acupuncture for chronic pain (individual patient data meta-analysis)

Updated individual patient data meta-analysis from the Acupuncture Trialists’ Collaboration, pooling about 39 trials and 20,827 patients with chronic back and neck pain, osteoarthritis, headache and shoulder pain. Acupuncture was statistically superior to both no-acupuncture and sham-acupuncture controls, so the effect is not solely placebo. But the difference over sham needling was small (roughly 0.15 to 0.23 standard deviations), and effects diminished only modestly over time. The honest reading: a real but small effect over a credible placebo, near the threshold of clinical importance.