Many religious people want to cling to the ancient belief in the supernatural, including prayer, and yet accept the conclusions and benefits of modern science. They can’t have it both ways. To study the natural world, scientists must have an implicit understanding that science operates only by natural, predictable processes, ones that can not be affected arbitrarily by an all-powerful deity.

One of the major ways that scientists provide proof of theories is by doing well designed studies, of which the “gold standard” is the large, randomized, prospective, controlled, double blind type. If such a study could be influenced by a personal god who responded to prayers to change the results, science would be in shambles. There would be no way to ever do a valid experiment since investigators couldn’t be sure that someone, somewhere, hadn’t uttered a specific or generic prayer that would affect the study. In short, science by its very nature, rejects any influence of prayer on the physical world.

Even though prayer is an irrational concept, could it nevertheless be tested scientifically? Francis Galton, the brilliant and eccentric half cousin of Charles Darwin, thought so and gave the idea scientific legitimacy. Galton was the father of biometry and a central figure in the founding of modern statistical analysis. He argued that regardless of how the prayers “may be supposed to operate,” the efficacy of prayer … is a perfectly appropriate and legitimate subject of scientific inquiry” because it can be tested statistically. He then proceeded to set up such studies.

In one statistical study, Galton examined data from a previous study by Guy on longevity. Galton first focused on clergy. He reasoned that clergy should be the longest lived of all since they were the most “prayerful class” of all and among the most prayed for. When Galton compared the longevity of eminent clergy with eminent doctors and lawyers, the clergy were the shortest lived of the three groups. Galton next focused on royalty, who were much prayed for, when compared to other members of the aristocracy. In analyzing the data on royalty, Galton concluded: “Sovereigns are literally the shortest lived of all who have the advantage of affluence.”

Galton looked for other statistical data. He examined the insurance rates for ships. He reasoned that ships carrying missionaries and pilgrims should have lower rates since frequent praying by the occupants should decrease the number of accidents. He found that the rates were the same; ships carrying missionaries and pilgrims sank just as often as other ships.

Following up on Galton’s statistical studies on prayer, Rupert Sheldrake, a Cambridge trained plant biologist, did one of his own. He examined the effects of prayer in India. Most people there prefer having a son, and a tremendous amount of praying goes into the effort to produce one. Sheldrake examined statistics of live male births in India and used data from England as a control where the preference for sons was less strong. He found that in both England and India there were 106 males to 100 females, just as in every other country. He stated, “If this enormous amount of psychic effort and praying of holy men were working, you would expect on average the percentage of live male births to be higher.”

Although these statistical studies from the nineteenth century strongly suggest that prayer is not effective, they do not meet the “gold standard,” as I previously described it, of a completely valid scientific study. But the media regularly mention a large number of contemporary studies that supposedly scientifically validate the beneficial effects of prayer on human health. So what is the truth in this matter? Actually, there are only three that meet the “gold standard.” Happily, the fact that there are only three studies considerably reduces the amount of information freethinkers need to acquire to refute frequent and erroneous claims.

Before we get into subjecting these three studies to critical analysis, let’s be sure that everyone understands what it means when we say that a finding in a scientific study is statistically significant. “Significant” has a very specific statistical meaning that applies in all scientific studies. A finding to be considered significant must be (.05) or less, which means the probability that it could be due to chance is 5 in 100. The main point to appreciate is that this figure, although reasonable, is strictly arbitrary. Therefore, the figure of (.05) is borderline significant, .04 (a probability of 4 in a 100 of being due to chance) is considered significant, and .06 (6 in 100) is considered not significant. I’ll bring out the importance of appreciating that the definition of “significant” is arbitrary in the Harris study.

The figure (.05) is the one accepted for “ordinary” scientific studies. But what criterion should be applied in proving a supernatural finding?  After all, as the old saw goes, extraordinary claims should require extraordinary proof, and this requirement should especially apply to claims of the supernatural. The James Randi Educational Foundation has a standing offer of one million dollars to anyone who can demonstrate any supernatural event under carefully controlled scientific conditions. The foundation has never had a single person who even got past the preliminary testing. Its members think that a study that would prove a claim of the supernatural should eliminate the possibility that the result could be by chance. They think a test should be devised where the possibility of a supernatural event happening would be in the range of 1 in 10,000,000, a far cry from 5 in 100.

One other point to be particularly aware of before we analyze the three studies is one that Robert Park brings out in his excellent book entitled Voodoo Science. He observes that a characteristic of voodoo science is that there are always very small differences in studies, ones that are just barely detectable, and ones that can’t be amplified in further investigations. These barely detectable positive results usually indicate flaws in the studies themselves rather than real findings.

Now let’s examine in some detail the three studies on intercessory prayer that were large, prospective, randomized, double blind ones, the only three that pass muster as valid scientific investigations of the effects of prayer on human health. Intercessory prayer (prayer at a distance) was chosen so that the placebo effect of direct prayer would be eliminated. All of these studies were done on coronary care unit (CCU) patients.

The first study was entitled “Positive Therapeutic Effects of Intercessory Prayer in a Coronary Care Unit Population” by Randolph Byrd, M.D., published in the Southern Medical Journal, July, 1988. Dr. Byrd stated: “My study concerning prayer and patients in a general hospital coronary care unit was designed to answer two questions: (1) Does intercessory prayer to the Judeo-Christian God have any effect on the patient’s medical condition and recovery while in the hospital? (2) How are these effects characterized, if present?

Over ten months, 393 patients admitted to the CCU at San Francisco General Hospital were randomized to an intercessory prayer group (192 patients) or to a control group (201 patients). After randomization, each patient in the prayer group was assigned to three to seven intercessors, who were all “born again” Christians (according to the Gospel of John 3:3) of various denominations. Dr. Byrd states: “The patients first name, diagnosis, and general condition, along with pertinent updates on their condition, were given to the intercessors. The intercessory prayer was done outside the hospital daily until the patient was discharged from the hospital. Under the direction of a coordinator, each intercessor was asked to pray daily for a rapid recovery and for prevention of complications and death, in addition to other areas of prayer they believed to be beneficial to the patient.”

The results were summarized in “Table 2” of the Byrd study entitled “Results of Intercessory Prayer.” There was no statistically significant difference between the prayer and control group in these measurements: days in CCU after entry; days in hospital after entry; number of discharge medications. Only when a list of 26 “New Problems, Diagnoses, and Therapeutic Events After Entry” was compiled was any statistically differences found and then only in 6 of the items: congestive heart failure (.03); diuretics (.05); cardiopulmonary arrest (.02); pneumonia (.03); antibiotics (.005); intubation/ventilation (.002). When Dr. Byrd subjected these items to multivariate analysis (a statistical method of analyzing the overall significance when multiple factors are positive), he found the prayer group to better the control group at the statistically significant level of (.0001).

He then showed a “Table 3” that is entitled “Results of Scoring the Post-entry Hospital Course” in which he constructed three categories, “Good, Intermediate, and Bad,” using a self-designed and previously not scientifically validated method. The prayer group bettered the control group at a level of (.01).

Although this study appears to meet the “gold standard” of a large, prospective, randomized, double blind investigation, scientists have pointed out a number of flaws:

•    The study was not “blinded” in two respects: 1) Janet Greene, the coordinator of the study, on whom Dr. Byrd depended for the collection of data, knew exactly who was being prayed for, and interacted regularly with the patients in the study. 2) “Table 3” was formulated by Dr. Byrd at the request of editors who initially evaluated his paper after the “blinding” had been removed.
•    There was no difference in clear-cut end points such as days in the CCU, days in the hospital, or mortality between the two groups. Only when complicated statistical analyses were done on a long list of items do any data emerge that favor the prayed for group – hardly evidence of an all-powerful deity. Also, if prayer had any effect, an overall improvement would be expected. Of the six items where the prayer group did better, four of them were of borderline statistical significance and only two clearly significant. Are we to conclude that the deity is only concerned with reducing antibiotic use and ventilating patients in the CCU? This study provides no information on the physicians involved in this study. This information could be important since certain physicians use antibiotics and intubate patients much more readily than others.
•    The method that Dr. Byrd used in his scoring in “Table 3” had not been validated by any previous studies.
•    When Irwin Tessman, Ph.D., professor of biological sciences at Perdue University, requested of Dr. Byrd that Dr. Tessman be allowed to review the raw data that went into the study, he was refused. Since Dr. Byrd’s claim is one of the supernatural, it would seem appropriate that all aspects of the study be reviewed by independent investigators.
•    The degree of obvious religiosity communicated by Dr. Byrd raises doubts that he could be completely objective on a scientific investigation of prayer, something that he deeply believes is effective. Under “Acknowledgments” at the end of the paper, he writes: “ … and Mrs. Janet Greene for her dedication to this study. In addition, I thank God for responding to the many prayers made on behalf of the patients.”

[continued in Part 2]

Related Posts:

1. Scientific Conclusion: Prayer Doesn’t Work – Part 2
2. Are Religion and Science Reconciling?
3. Theoretically Speaking
4. Faith: Religion’s Achilles Heel

Tags | critical thinking, Religion, Science