The Why Files The Why Files --

Prayer at a distance: Does it heal?


Pray tell
Can intercessory prayer help strangers?Can prayer at a distance heal? Not according to a large new study, which tested whether the prayers of strangers can speed recovery from open heart surgery. In the United States, the majority of surgery patients think or know somebody will be praying for them. But is prayer so powerful that strangers can speed healing enough to show up in a formal clinical trial?

The question arises because a few trials have found that the prayers of strangers can speed healing, and because:

"Prayer for others" is the second-most common alternative medicine practice in the United States (first is "prayer for self").

At some religious hospitals, chaplains and volunteers pray for people they don't know.

There is strong evidence that spirituality and religiosity are good for the health of those who practice them (see " Religious Involvement..." in the bibliography).

Many people believe various "hands-off" techniques like energy therapy and spirit healing can improve health.

If prayer at a distance does work, maybe it should be used more systematically.

The central question of the ongoing studies of intercessory prayer (IP) is this: Can you be helped by the prayers of people who you don't know, and who don't know you? (Before you argue that prayer seldom works this way, let's observe that the studies are easier to interpret if they are set up this way.)

Not helpful
The recent report (see "Study of the Therapeutic..." in the bibliography) found that IP did not reduce complications after coronary bypass surgery. In fact, people who knew they were being prayed for had significantly more complications than the other two groups. The Study of the Therapeutic Effects of Intercessory Prayer (STEP) established three groups, each with about 600 patients:

Group 1 got IP, but members were not told whether they were getting it.

Group 2 did not get the prayers, and also did not know if they were getting prayers.

Group 3 got IP, and were told about it

The praying was done by Christian prayer groups, who were told the date of surgery and the patient's first name and last initial. The pray-ers were asked to pray for "a successful surgery with a quick, healthy recovery and no complications," and to pray twice daily for 14 days, starting on the eve of surgery.

"The primary goal of STEP was to evaluate whether intercessory prayer or the knowledge of receiving it would influence recovery after bypass surgery," said Jeffrey Dusek, a psychologist at Harvard Medical School and co-principal director of the trial. But to anyone who thinks such long-distance prayer can heal, STEP was a step in the wrong direction, since, as the authors wrote, "intercessory prayer itself had no effect on whether complications occurred" after bypass surgery.

Blue stained glass window illuminates church congregation below
Photo: Washington National Cathedrall

Is prayer dangerous?
The second conclusion of STEP was more troubling. "Patients who were certain that intercessors would pray for them had a higher rate of complications than patients who were uncertain but did receive intercessory prayer," the authors also wrote. We asked M. Bruce Edmonson, a professor of pediatrics at the University of Wisconsin-Madison who specializes in epidemiology, if intercessory prayer might be dangerous, but he said, "the numbers don't convincingly show harm from knowing you are being prayed for."

Surgeons clad in blue scrubs operate on heart patient, drawing blood through machine.Patients did not benefit from distant prayer, in a study released this month. Photo: Edward Joseph, University of Wisconsin School of Medicine and Public Health.

But cardiologist Mitchell Krucoff of Duke University, author of a recent study of IP that we'll cover shortly, noted a " striking element of the STEP report," concerning the high rate of complications in group 3. "The investigators take an almost casual approach toward any explanation, stating only that it may have been a chance finding. It is rather unusual to attribute a statistically significant result in the primary end point of a prospective, multicenter randomized trial to chance."

The STEP trial, Krucoff added, highlighted a new concern for prayer studies: safety" (see "From Efficacy to Safety..." in the bibliography).

Not so fast, said Edmonson, who suggested we focus on the "study's best estimate (the magnitude) of harm and how precisely estimated it was (the confidence interval)." The risk of complications in STEP's group 3 (got prayer, and knew it) ranged from 1.02 to 1.28 times higher than the risk in group 1 (got prayer, but did not know it).

Given that the risk of death was actually a bit lower in group 3, Edmonson observes that the study may say little about the true "risks" of knowing that somebody is praying for you. "Since the worst-case estimate for harm is modest and the authors' estimate a bit imprecise, it may be best to consider as 'unresolved' the question of whether intercessory prayer (and knowledge thereof) really is harmful and, even if it proves to be so, whether the 'harm' is clinically important."

Towering, ornate cathedral is lit against the purple night sky
Photo: Washington National Cathedral

Edmonson raised a different criticism: the absence of a control group. Why did no group get no prayer, and know about it? "The study design is lacking," Edmonson said, because instead of testing the effect of IP, it tested "the possibility that intercessory prayer, certainty that one is the object of prayer, or some combination of the two, might reduce the risk of complications."

The absence of a control group caused some journals to reject the study, STEP authors admitted at an April press conference (we didn't get an interview with them, but we did read the transcript). "In a typical balanced study, we would have had a Group 4," said Dusek, but "we were concerned that knowledge of not receiving an intercessory prayer may not be in the best interests of someone undergoing cardiac surgery. We thought for certain that that would increase stress levels."

And increased stress is the last thing you need before surgery to swap out clogged heart arteries. About half of patients have significant complications within a month.

The STEP authors offered several possible explanations for their negative result on prayer's effectiveness. Maybe it was due to the formulaic prayer, or the lack of contact between the pray-ers and the patients. Maybe IP does not speed healing after surgery, or specifically after bypass surgery.

Here's one study that did find a cardiac benefit from long-distance prayer.


Megan Anderson, project assistant; Terry Devitt, editor; S.V. Medaris, designer/illustrator; David Tenenbaum, feature writer; Amy Toburen, content development executive

©2021, University of Wisconsin, Board of Regents.