A Collection of Strange Beliefs, Amusing Deceptions, and Dangerous Delusions

From Abracadabra to Zombies

Healing Prayer (HP) & Distant Healing (DH)*
Robert Todd Carroll
part 1
(posted March 6, 2008)

Healing or intercessory prayer is the expression used to describe the process of asking God, some spirit, or some mysterious “energy” to intervene and alter the natural course of some process affecting one’s own or another’s health. Praying for the recovery of the sick or injured is widely practiced. According to the National Institutes of Health (NIH), prayer is the most commonly used "alternative medicine" in the U.S. According to a survey of more than 31,000 adults conducted as part of the Centers for Disease Control and Prevention's 2002 National Health Interview Survey. NIH considers prayer a "mind-body therapy," a category that also includes biofeedback, meditation, guided imagery, hypnosis and deep breathing exercises. From 2000-2004, the federal government contributed $2.3 million in financing for prayer research (Carey). The NIH survey found that 55 percent of Americans have used "prayer for health reasons," 52 percent "prayed for their own health," 31 percent had asked others to pray for their health, 23 percent had prayed for health in a prayer group, and 5 percent had used a healing ritual (Washington Times). Prayer may be on the decline, however. The National Institutes of Health reported in May 2004 that according to a survey about 43 percent of adults say they've used prayer for their own health (down 9%) and 24 percent said they prayed for the health of others. The later survey also found that prayer topped the list of most popular alternative therapies.

Prayer is often a devout person's natural first reaction when learning that they, a family member, or a friend is ill or has been in an accident (Religious Tolerance). Our concern in this course is prayer as a type of psychokinesis (PK). Thus, we are not going to evaluate the scientific studies that are concerned with the effects of such practices as routine praying or meditating on the health and wellbeing of the individual practitioner. Our concern is only with those studies that have tried to determine whether praying for others has any effect on the health of those who are prayed for.

The history of distant healing studies shares much in common with the history of the PK studies. Many studies are too small to justify drawing conclusions from them; many are poorly designed or controlled; statistical formulas are misused; data have been massaged after the studies are completed; some of the studies have looked for correlations of prayer to so many factors that it was inevitable that they would find some statistically significant relations in their data just by chance (Texas sharpshooter fallacy); and replication has been a major problem. Nevertheless, several studies are worth examining to explore their methodologies and learn what, if anything, is known or is likely to be discovered by further research into distant healing.

It has been taught for centuries by clergy of many faiths that intercessory prayer works. Many people are convinced that their prayers have been answered. It seemed to some researchers that it would be a simple matter to set up an experiment and see if our intuitions match reality. However, certain problems immediately emerge: how do you measure a dose of prayer and how do you control for all those prayers people are praying for the whole world, for their friends, or for their family? Can you overdose on prayer? Is there such a thing as a fatal dose of prayer. The dose seems doomed to be rather subjective and there has to be some sort of assumption that cross-over prayers will cancel each other out. Also, it is assumed that prayer is never harmful. Is this assumption justified?

The Studies

1) 1988. Dr. Randolph Byrd published the results of his double-blind randomized control study on healing prayer with cardiac patients. In his article, he mentions three previous scientific/medical studies on the efficacy of prayer: (1.) Francis Galton’s 1872 article “Statistical Inquiries into the Efficacy of Prayer.” Galton looked at the effects of prayer in the clergy on British sovereigns and found no salutary effects. He chose this subject because the Anglican clergy pray for their sovereigns on a daily basis. Unfortunately, Galton found: “The sovereigns are literally the shortest lived of all who have the advantage of affluence. The prayer has therefore no efficacy, unless the very questionable hypothesis be raised, that the conditions of royal life may naturally be yet more fatal, and that their influence is partly, though incompletely, neutralised by the effects of public prayers.” (2.) In C. R. Joyce and R. M. Welldon’s 1965 study of rheumatics, the prayer group fared better in the first half, "but in the second half the control group did better" ("The efficacy of prayer: A double-blind clinical trial," Journal of Chronic Disease, 18:367-377, 1965).  (3.) And in 1969, P. J. Collipp's findings regarding prayer and leukemia "did not reach significance" ("The efficacy of prayer: A triple blind study," Medical Times, 97:201-204, 1969). [from Posner]

It took Dr. Byrd, a cardiologist, five years to get his study published! “Positive therapeutic effects of intercessory prayer in a coronary care unit population” was published in the Southern Medical Journal (81, no. 7, pp. 826-829). Byrd claimed he had evidence that coronary patients benefited from blind, distant intercessory prayer.

Byrd endeavored to answer these questions: (1) Does intercessory prayer (IP) to the Judeo-Christian God have any effect on a CCU patient’s medical condition and recovery? (2) How are these effects manifested, if present.

The study took place between August 1982 and May 1983, when 393 patients signed informed consent papers upon admission to the San Francisco General Hospital CCU, and were entered into a double-blind, randomized study. (The remaining fifty-seven patients admitted during this period cited various reasons for refusing to participate.) A computer-generated list randomly assigned patients to either the IP or the control group, and neither they, nor the CCU doctors and staff, nor Randolph Byrd were aware of which patients were assigned to which group. (see Posner)

Intercessors chosen to pray for the IP-group patients were “'born again' Christians (according to the Gospel of John 3:3) with an active Christian life as manifested by daily devotional prayer and active Christian fellowship with a local church.” Each IP patient "was assigned to three to seven intercessors. . . . The [IP] was done outside of the hospital daily until the patient was discharged . . . each intercessor was asked to pray daily for a rapid recovery and for prevention of complications and death."

The IP group consisted of 192 patients and the control group of 201. Analyses revealed no significant statistical differences between the health of the two groups upon admission. “Thus it was concluded that the two groups were statistically inseparable and that results from the analysis of the effects of [IP] would be valid.” The mean age of the IP patients was two years younger than that of the control patients, a difference deemed statistically insignificant.

The most striking flaw in this study's methodology is one forthrightly acknowledged by Byrd. "It was assumed that some of the patients in both groups would be prayed for by people not associated with the study; this was not controlled for. . . . Therefore, 'pure' groups were not attained in this study." In other words, the focus of the study - prayer - was "not controlled for," except that three to seven intercessors were assigned to pray daily for each patient in the IP group, and none was assigned to the controls. Thus, although unlikely, it is nevertheless theoretically possible that the control group received as many prayers as did the IP group, if not more. (Posner)

So, the main thing being studied couldn’t be controlled for. Interesting. The good news:

in the IP group, 5 percent fewer patients needed diuretics, 7 percent fewer needed antibiotics, 6 percent fewer needed respiratory intubation and/or ventilation, 6 percent fewer developed congestive heart failure, 5 percent fewer developed pneumonia, and 5 percent fewer suffered cardiopulmonary arrest.

The bad news:

...no significant differences were found among the other twenty categories, including mortality, despite explicit prayers "for prevention of . . . death."

Byrd devised 26 categories and found significant positive differences in the IP group in 6 categories (23% of his categories). Seventy-seven percent of his categories found no improvement in the IP group. Was this just coincidence or does prayer work for some complications but not others?

In any case, the Byrd study has not been replicated. One study that tried, the Harris study (see below), might seem  to replicate Byrd’s findings, but we'll see that the Harris study was fatally flawed. Recently, Herbert Benson published the results of his randomized, double-blind study of the effects of healing prayer on cardiac patients (see below). He failed to find any significant difference in the IP group.

2). 1998. The Sicher/Targ et al. study: “A Randomized Double-Blind Study of the Effect of Distant Healing in a Population With Advanced AIDS--Report of a Small Scale Study.” The Western Journal of Medicine. December 1998. by Fred Sicher, Elisabeth Targ, Dan Moore II, and Helene S. Smith. It appears to be an extremely well-designed double-blind, controlled study. However, Sicher and his associates, at Targ’s urging, changed the goal of the study and had a statistician mine the data after it had been completed. The original goal was to see if prayer could lower the death rate for AIDS patients. Since only one of the patients in the study died, there was nothing to report on that count. The published study, however, claimed that the aim was to measure prayer against a long list of symptoms—along the lines of the Byrd and Harris studies. A researcher (Sicher) familiar with each participant's medical records went through the data after the original study was completed to determine which patients had which symptoms. It was a bit of a fluke that Sicher and Targ’s deception was exposed by Po Bronson in Wired magazine.

The 1998 study was designed to be a follow-up to a 1995 study of 20 patients with AIDS, ten of whom were prayed for by psychic healers. Four of the patients died, a result consistent with chance, but all four were in the control group, a stat that appeared anomalous enough to these scientists to do further study. I don't know whether evidence was suppressed or whether the scientists doing the study were simply incompetent, but the four patients who died were the four oldest in the study. The 1995 study did not control for age when it assigned the patients to either the control or the healing prayer group. Any controlled study on mortality that does not control for age is by definition not a properly designed study.

The follow-up study suppressed evidence, yet it is "widely acknowledged as the most scientifically rigorous attempt ever to discover if prayer can heal" (Bronson 2002). The standard format for scientific reports is to begin with an abstract that summarizes the contents of the report. The Abstract for the Sicher-Targ report notes that controls were done for age, number of AIDS-defining illnesses, and T cell count. Patients were randomly assigned to the control or healing prayer groups. The study followed the patients for six months. "At 6 months, a blind medical chart review found that treatment subjects acquired significantly fewer new AIDS-defining illnesses (0.1 versus 0.6 per patient, P = 0.04), had lower illness severity (severity score 0.8 versus 2.65, P = 0.03), and required significantly fewer doctor visits (9.2 versus 13.0, P = 0.01), fewer hospitalizations (0.15 versus 0.6, P = 0.04), and fewer days of hospitalization (0.5 versus 3.4, P = 0.04)." These numbers are very impressive. They indicate that the measured differences were not likely due to chance. Whether they were due to healing prayer (HP) is another matter, but the scientists conclude their abstract with the claim: "These data support the possibility of a DH effect in AIDS and suggest the value of further research." Two years after the publication of these sensational sounding results, Elisabeth Targ was granted $1.5 million from the National Institutes of Health Center for Complementary and Alternative Medicine to do two further studies on the healing effects of prayer. Both studies would involve 150 subjects. One was going to involve AIDS patients and the other was going to involve patients with brain cancer. Ironically, Targ died of glioblastoma (a rare form of brain tumor) in 2003, while studying the effects of distant prayer on glioblastoma patients and despite being one of the most prayed-for persons on the planet. (See "A Magical Death" by Phillips Stevens, Jr.)

What the Sicher-Targ study didn't reveal was that the original study had not been designed to do any of the measurements they report as significant. Of course, any researcher who didn't report significant findings just because the original study hadn't set out to investigate them would be remiss. The standard format of a scientific report allows such findings to be noted in the Abstract or in the Discussion section of the report. It would have been appropriate for the Sicher-Targ report to have noted in the Discussion section that since only one patient died during their study, it appears that the new drugs being given AIDS patients as part of their standard therapy (triple-drug anti-retroviral therapy) were having a significant effect on longevity. They might even have suggested that their finding warranted further research into the effectiveness of the new drug therapy. However, in its introductory remarks, the Sicher-Targ report gives the impression that the researchers already knew the new drug therapy would work (making them clairvoyant!) and that is why they changed the design from the earlier pilot study. They now claim they never intended to replicate that study. Instead, they write:

an important intervening medical factor changed the endpoint in the study design. The pilot study was conducted before the introduction of "triple-drug therapy" (simultaneous use of a protease inhibitor and at least two antiretroviral drugs), which has been shown to have a significant effect on mortality. [Here, they cite a study published in 1997, which is after their study was completed!] For the replication study (July 1996 through January 1997, shortly after widespread introduction of triple-drug therapy in San Francisco), differences in mortality were not expected and different endpoints were used in the study design. Based on results from the pilot study, we hypothesized that the DH treatment would be associated with 1) improved disease progression (fewer and less severe AIDS-defining diseases [ADDs] and improved [CD4.sup.+] level), 2) decreased medical utilization, and 3) improved psychological well-being.

The above description of why they changed the endpoint is grossly misleading. It was only after they mined the data once the study was completed that they came up with the suggestive and impressive statistics that they present in their published report. Under certain conditions, mining the data would be perfectly acceptable. For example, if the original study was designed to study the effectiveness of a drug on blood pressure but found that the experimental group had no significant decrease in blood pressure but did have a significant increase in HDL (the "good" cholesterol), you would be remiss not to mention this. You would be guilty of deception, however, if you wrote your paper as if your original design was to study the effects of the drug on cholesterol and made no mention of blood pressure.

So, it would have been entirely appropriate for the Sicher-Targ report to have noted in the Discussion section that they had discovered something interesting in their statistics:  Hospital stays and doctor visits were lower for the HP group. It was inappropriate to write the report as if that was one of the effects the study was designed to measure when this effect was neither looked for nor discovered until Moore, the statistician for the study, began crunching numbers looking for something of statistical significance after the study was completed. Again, crunching numbers and data mining after a study is completed is appropriate; not mentioning that you rewrote your paper to make it look like it had been designed to crunch those numbers isn't.

It would have been appropriate in the Discussion section of their report to have speculated as to the reason for the statistically significant differences in hospitalizations and days of hospitalization. They could have speculated that prayer made all the difference and, if they were competent, they would have also noted that insurance coverage could make all the difference as well. "Patients with health insurance tend to stay in hospitals longer than uninsured ones" (Bronson 2002). The researchers should have checked this out and reported their findings. Instead, they took a list of 23 illnesses associated with AIDS and had Sicher go back over each of the 40 patient medical charts and use them to collect the data for the 23 illnesses as best he could. This was after it was known to Sicher which group each patient had been randomly assigned to, prayer or control. The fact that the names were blacked out, so he could not immediately tell whose record he was reading, does not seem sufficient to justify allowing him to review the data. There were only 40 patients in the study and he was familiar with each of them. It would have been better had an independent party, someone not involved in the study, gone over the medical charts. Sicher is "an ardent believer in distant healing" and he had put up $7,500 for the pilot study (ibid.) on prayer and mortality. His impartiality was clearly compromised. So was the double-blind quality of the study.

In any case, this study also suffers from the Texas sharpshooter fallacy. Of their list of 23 items, they found six that showed statistical significance. That means that there were 17 items prayer didn't affect. Sicher needs to explain why prayer is so fickle.

* These are the notes I used in a course I taught on critical thinking about the paranormal. I've added an editorial note or two, now that I'm retired and don't give this lecture anymore.

>> continue to part 2

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