Sham acupuncture using toothpicks instead of needles may be as effective as the real thing at easing back pain. That's the conclusion of a study conducted at the Group Health Center for Health Studies in Seattle. Investigators compared back-pain sufferers who received acupuncture with a group poked with toothpicks in the same spots, as well as a group who received other therapy including massage. Sixty percent of subjects in the acupuncture groups reported improvement eight weeks later, compared with 40% of the controls. The acupuncture recipients could not see which treatment they got. It's possible that more than the placebo effect was at work in the toothpick group, since real acupuncture points were poked, perhaps providing real relief. But this may also be one more example of the analgesic power of the trusting mind.