These devices are low-current stimulators that people can wear at home for a short period. A systematic review was conducted of literature regarding these devices. It concluded that there is not evidence that these devices have clinically meaningful effects on fibromyalgia, headache, neuromusculoskeletal pain, degenerative joint pain, depression, or insomnia. There was low strength evidence of a small benefit in patients with anxiety and depression. This is in contrast to substantial evidence regarding the effectiveness of antidepressant medications, psychotherapy, TMS, ECT, DCS, VNS, and ketamine.