I’ve suggested that the main function of medicine is to show that we care. I’ve suggested that we spend a lot on medicine to signal our care, and that this can explain the placebo effect, wherein the mere appearance of care increases health. Some apparently confirming evidence:
Parkinson’s Disease patients secretly treated with a placebo instead of their regular medication performed better when told they were receiving a more expensive version of the “drug,” … While most people think of a placebo as a sugar pill that replaces a real medication, the impact more commonly comes from “the engagement between patients and clinicians,” in particular the way doctors create expectations that their efforts will help, Kaptchuk said. That includes a good relationship between doctor and patient; certain medical rituals, such as taking blood pressure and a medical history; and the “color, shape, number and cost” of the placebo drug. (more; the study)
Now this study is hardly definitive – it had only twelve subjects, and the placebo difference is only significant at the 3.4% level. But I guess that it will be verified in larger trials.