 Many studies published about dry needling are not randomized, contain small sample sizes, and have high dropout rates.A review recommended the usage of dry needling, compared to sham or placebo, for decreasing pain immediately after treatment and at 4 weeks in patients with upper quarter myofascial pain syndrome.However, the authors caution that "the limited number of studies performed to date, combined with methodological flaws in many of the studies, prompts caution in interpreting the results of the meta-analysis performed".