By Yvonne Kao
A study1 on the effect of intercessory prayer on recovery was reported in the American Heart Journal. The study procedure, in short: Cardiac bypass patients all around the country were randomly assigned to one of three experimental groups:
- Uncertain/No Prayer: Patients in this group were told they might or might not receive prayers; they did not receive prayers.
- Uncertain/Prayer: Patients in this group were told they might or might not receive prayers; they did receive prayers.
- Certain/Prayer: Patients in this group were told they would receive prayers; they did receive prayers.
This study was reported under headlines like, “Intercessory Prayer Has No Major Effect on Recovery (BeliefNet) 2, “Long-Awaited Medical Study Questions the Power of Prayer” (New York Times)3, “Study Fails to Show Healing Power of Prayer (Yahoo! News)4, and “Prayer Does Not Heal the Sick, Study Finds (Times Online)5. These headlines may be catchy, but they do extreme violence to the actual science.
This brings me to my first main point: Be skeptical. Often journalists (and sometimes scientists) exaggerate or omit certain facts in order to tell a better story.
The title of the paper that appeared in the American Heart Journal is “Study of the Therapeutic Effects of Intercessory Prayer (STEP) in Cardiac Bypass Patients”. Only one of the above linked articles uses the word intercessory in its headline, the rest lead you to believe that the study addresses the entire construct of prayer, which it doesn’t.
Intercessory prayer is prayer made on behalf of another person. In this case, three different Christian prayer groups from around the country were praying for cardiac patients that they did not know, nor would they ever know. This study makes absolutely no comment on the value of private prayer, or prayers from family and friends, or even prayers from a random person you met on the bus, so anybody who’s giddy or distraught over the “It doesn’t pay to pray!” headlines needs to settle down, because this study is very, very far from answering that question.
This brings me to my second main point, which I’m going to make by quoting
a paragraph from the New York Times article above:
“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.”
Science is, by definition, subject to what humans can understand and observe. God is, by definition, beyond what humans can understand and observe. Relationships with God are individual and personal. Science is about averages across populations. Thus, science is an utterly inadequate tool to address matters of religion. The best science can do is say, “well, it doesn’t look like there needs to be divine intervention for this to happen.”
What can we conclude from this study? Intercessory prayer by total strangers does not appear to have a detectable systematic benefit on cardiac bypass patients’ recovery over a 30-day window. Certainty of receiving intercessory prayer may be associated with a slightly higher risk of complications.
I would like to point out a few key words/phrases in the above paragraph.
- Detectable. Although researchers were not able to detect a difference, this does not mean no difference existed. The researchers’ measurement methods may not have been powerful or accurate enough to detect the difference.
- Systematic. It is possible that intercessory prayer had a great effect on some patients, but that the number of patients affected was small, and these patients did not have anything obvious in common.
- 30-day window. The researchers may have found different results with a longer or shorter time window.
That’s a lot less exciting than “It doesn’t pay to pray,” isn’t it?
The execution of this study seemed to be reasonably rigorous, however there were major limitations imposed by the study design–the 30-day recovery window, the disruption of the prayer groups’ typical prayer routines, and participants’ awareness that they’re part of a prayer study, among other things. While these are good experimental design choices in that they make the study easier to manage and the results easier to interpret, the tradeoff is that the circumstances in the study may not reflect the circumstances that matter in the real world.
This study, like most studies involving human participants potentially suffers from a self-selection bias in the study sample. In most cases, you need to get informed consent from an individual before they can participate in your study, and in some cases, the people who choose to participate in the study may be fundamentally different than the people who choose not to participate in the study. I checked the demographics reported in the journal article and it appears that the religious affiliations of study participants is generally representative of broader U.S. population; however it might still be that study participants place more value on spiritual healing than the population at large.
Although this study can’t really say much about prayer as a whole, it’s a good mental exercise to ask, “What if they did find a benefit of intercessory prayer? Wouldn’t that ‘prove’ that prayer works?” [The use and abuse of the word “prove” in science is a topic for another day.] And the answer is…maybe. If only the group that was certain of receiving prayers saw improvement, then certainty could be the critical factor. If the two groups that were prayed for saw improvement while the third group didn’t, that would be stronger evidence, since (in theory) the two uncertain groups were treated equally, except for the prayers. However, a finding that prayer works wouldn’t necessarily explain why it works, so we still couldn’t conclude anything about God.
When reading and interpreting scientific findings, it is always helpful to do two things: 1) Really look at what the scientists are examining and measuring instead of trusting that the findings are being reported fairly. 2) Consider alternate explanations for the pattern of data. In this study, there are a number of possible explanations for the findings, thus we should be careful about jumping to the conclusion that prayer provides no benefit.
- Benson, H., Dusek, J. A., Sherwood, J. B., Lam, P., Bethea, C. F., Carpenter, W., Levitsky, S., Hill, P. C., Clem, D. W., Jain, M. K., Drumel, D., Kopecky, S. L., Mueller, P. S., Marek, D., Rollins, S., & Hibberd, P. L. (2006). Study of the therapeutic effects of intercessory prayer (STEP) in cardiac bypass patients: A multicenter randomized trial of uncertainty and certainty of receiving intercessory prayer. American Heart Journal, 151(4), 934-42.
- Banks, A. M. (2006). Study: Intercessory prayer has no major effect on recovery. BeliefNet. Retrieved online 14 April 2006.
- Carey, B. (2006, March 31). Long-awaited medical study questions the power of prayer. The New York Times. Retrieved online 14 April 2006.
- Conlon, M. (2006, March 31). Study fails to show healing power of prayer. Yahoo! News. Retrieved online 14 April 2006.
- Knight, S. & Agencies. (2006, March 31). Prayer does not heal the sick, study finds. Times Online. Retrieved online 14 April 2006.