http://www.boston.com/news/nation/articles/2006/03/31/no_benefit_of_prayer_found_after_surgery/

Quote from: boston heraldThe study of more than 1,800 heart bypass surgery patients found that those who had other people praying for them had as many complications as those who did not. In fact, one group of patients who knew they were the subject of prayers fared worse.

Surprise surprise.

I dont doubt that prayer, meditation, and the like can be beneficial if the patient participates.