Abstract
The trial by Gale et al (pages 185-189) is a valuable example of a negative result - the sort of finding that is published less often than a positive one. But, we can learn from the failure, both in understanding correct treatment and in planning future trials. Patients were recruited in a clinic where repeated treatment by nerve blocks is used as a palliative measure for chronic pain of all types. They were then offered the choice of entering a group with cognitive behavioural therapy or continuing with nerve blocks. For ethical reasons, patients could freely leave either branch of the trial without prejudice. At the onset, one of 34 patients in the nerve-block group left, while 12 departed from the cognitive therapy group. All 33 patients remaining in the nerve block group completed the eight-week trial, while only four of 34 patients completed it in the cognitive therapy group.