Cochrane Database Syst Rev. 2017 Jan 12;1:CD010671. doi: 10.1002/14651858.CD010671.pub2. Yoga treatment for chronic non-specific low back pain.. "There is low- to moderate-certainty evidence that yoga compared to non-exercise controls results in small to moderate improvements in back-related function at three and six months. Yoga may also be slightly more effective for pain at three and six months, however the effect size did not meet predefined levels of minimum clinical importance. It is uncertain whether there is any difference between yoga and other exercise for back-related function or pain, or whether yoga added to exercise is more effective than exercise alone."