"The patients were broken into three groups. Two were prayed for; the third was not. Half the patients who received the prayers were told that they were being prayed for; half were told that they might or might not receive prayers.
The researchers asked the members of three congregations — St. Paul's Monastery in St. Paul; the Community of Teresian Carmelites in Worcester, Mass.; and Silent Unity, a Missouri prayer ministry near Kansas City — to deliver the prayers, using the patients' first names and the first initials of their last names."
It would seem to be an obvious scientific question about a scientific experiment, but the answer was not forthcoming, nor did I ever here of any followup experiments.
"Prayers offered by strangers had no effect on the recovery of people who were undergoing heart surgery, a large and long-awaited study has found.-- Long-Awaited Medical Study Questions the Power of Prayer
And patients who knew they were being prayed for had a higher rate of post-operative complications like abnormal heart rhythms, perhaps because of the expectations the prayers created, the researchers suggested."
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"The problem with studying religion scientifically is that you do violence to the phenomenon by reducing it to basic elements that can be quantified, and that makes for bad science and bad religion," said Dr. Richard Sloan, a professor of behavioral medicine at Columbia and author of a forthcoming book, "Blind Faith: The Unholy Alliance of Religion and Medicine."