Studies have investigated whether intercessory prayer helps heal people recovering from illness, like this boy in an intensive care unit in Sydney, Australia.

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Studies on Healing Prayer

In 1988, the physician Randolph Byrd shocked the world with the results of a study he had conducted five years earlier on the effects of prayer on cardiac patients. Byrd studied 393 patients who checked into a coronary care unit in a San Francisco hospital. The patients were “statistically inseparable,” meaning their condition and symptoms were all similar. Each was randomly assigned to one of two groups: those who received intercessory prayer and those who didn't. Neither the doctor nor the patients knew who was in which group.

Byrd gave the first name, diagnosis and condition of an IP patient to different groups of three or four active Christians from several denominations. These groups prayed for their patient daily throughout the patient’s stay, away from the hospital, without meeting the patient. They prayed for a timely, easy recovery and one free from complications.

When the study concluded, Byrd found that there was indeed a significant difference in the quality of recovery among patients who received prayer: They fared better on average than their fellow patients who did not receive prayer. Almost 85 percent of the IP group scored “good” on the rating system used by hospitals to rate a patient’s response to treatment. They were less likely to have a heart attack, need antibiotics or require intervention like ventilation or intubation. By contrast, 73.1 percent of members of the control group scored “good” [source: Byrd].

Byrd’s study launched a spate of similar studies. Though he also received much criticism, Byrd provided a model for other studies on prayer. One, conducted by a group led by William Harris in Kansas City, Mo., in 1999, replicated Byrd’s study. Harris’ group found somewhat similar results: 67.4 percent of the IP group fared “good,” compared with 64.5 of the control group [source: Harris, et al.].

But other studies have not produced similar findings. The Study of the Effects of Intercessory Prayer (STEP), a major study published in 2006 in the American Heart Journal, looked at patients at six medical centers in the United States. This study divided patients who all had coronary artery bypass graft surgery into three groups:

  • those who received prayer from an outside group, but who were not aware they were being prayed for
  • those who did not receive prayer
  • those who were aware they were being prayed for

Not only did the STEP study not find the same results as Byrd’s and Harris’ studies, it revealed a wholly unexpected aspect. Those receiving prayer suffered more complications than those who did not receive prayer (52 percent to 51 percent). More surprisingly, those who were aware they had received prayer fared the worst: 59 percent of this group had complications following their surgery [source: Harvard].

A 2005 study led by Duke University researchers investigated the effects of prayer, as well as touch, music and imagery therapy (MIT), which was delivered to patients at their bedside. The results showed little difference in recovery among the people who received prayer alone, the group that received only MIT, the group that received both prayer and MIT and the fourth group which received neither prayer nor therapy. It did, however, find that there was a slight difference among the rate of death within six months of treatment between the groups. The group that received both distant intercessory prayer and MIT had the lowest rate of death within six months, although it wasn’t considered a significant difference by the researchers conducting the study [source: Duke].

So what gives? Has the power of prayer been effectively proven or disproven? Has the final word been issued? Read the next page to find out about the problems with conducting studies into the supernatural.