There are double-blind studies on acupuncture, by using "trick-needles" that don't penetrate the skin but look like they do. This study introduces them and sho

There are double-blind studies on acupuncture, by using "trick-needles" that don't penetrate the skin but look like they do. This study introduces them and shows that acupuncturists can't well distinguish both types: https://www.biomedcentral.com/1472-6882/7/31 https://www.biomedcentral.com/1472-6882/7/31 This study uses them to check for differences in pain-relief (there are no differences): https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2765771/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2765771/