It's been tested on a group of 1,162 patients who suffered from chronic low back pain for an average of eight years. The group received one of three therapies: acupuncture, which involved 10 sessions, twice a week, sham acupuncture, where the needles were not properly inserted, and conventional therapy, which included drugs, physical therapy and exercise.

After six months, 48 per cent of those in the acupuncture group reported a dramatic reduction in back pain compared with just 20 per cent who were receiving conventional treatments. Interestingly,44 per cent of those given 'sham' acupuncture' also reported an improvement.