Prayer in the Science Lab, Part 2

by Cheyenne Francis Reiswig

Dr. Randolph Byrd is a heart specialist, and he’s also a researcher. A little over 25 years ago, he conducted a study that kicked off the medical community’s interest in researching prayer. The study focused on the effects of intercessory prayer, or prayer offered for someone else.

For subjects, Dr. Byrd used 393 patients in the Intensive Heart Care Unit at San Francisco General Medical Center. Computers randomly decided which half of the patients would be prayed for, and which would not.1 Throughout the study, the patients and their doctors remained unaware of who was in which group.2


At the end of the study, Dr. Byrd found that the prayed-for group had fewer cases of congestive heart failure, pneumonia, and cardiac arrests. In addition, fewer of these patients required antibiotics, diuretics, and intubation or ventilation.3 Such impressive results attracted the attention of the medical world, and Dr. Byrd’s study became famous in the realm of prayer research.

Dr. William Harris also conducted a prayer study. His study was so confidential that he didn’t tell either his patients or the medical staff that they were part of the study. His group consisted of nearly 1,000 heart patients at the Mid-America Heart Institute in Kansas City, Missouri. For four weeks, Christian volunteers prayed daily for roughly half of the patients. When Dr. Harris reviewed the medical records, he discovered that the prayed-for group had fared 10–11% better than the others.4

Further studies have been conducted on the effects of intercessory prayer, with varying results. In a study on patients with rheumatoid arthritis, distant intercessory prayer did not have significant results. But the same study showed that face-to-face intercessory prayer—in other words, prayer offered with the patient present—resulted in definite improvement over one year.5

Not every study affirms prayer’s power. Some studies showed no difference in outcome between those who received prayers and those who didn’t. Some even seemed to show a slightly negative outcome for a group that knew they were being prayed for, compared to those who didn’t know or who weren’t receiving prayers. Still, when Professor David Hodge of Arizona State University pooled all the data from 17 major studies, he found that the data indicated a positive outcome from prayer.6

It’s exciting when science affirms Bible promises, calling the attention of the secular world to God’s power. Yet, critics quickly point out that the prayer studies didn’t showcase dramatic improvements and recoveries. The physical benefits of prayer were modest, at best.

Actually, we shouldn’t expect anything else. First, it isn’t likely that every person recruited to pray was an obedient, humble child of God whose “effectual fervent” prayers avail much.7 In other words, the study authors couldn’t know which of their intercessors really had the right to claim God’s promises in behalf of the patients. Also, neither doctors nor intercessors could know what was truly best for their patients in view of eternity. Only God knows how best to answer prayer.

There is another important reason that prayers for the sick sometimes seem to accomplish little. It’s simple: God expects us to care for our own health as much as we can. “Many have expected that God would keep them from sickness merely because they have asked Him to do so. . . . God will not work a miracle to keep those from sickness who have no care for themselves, but are continually violating the laws of health and make no efforts to prevent disease. When we do all we can on our part to have health, then may we expect that the blessed results will follow, and we can ask God in faith to bless our efforts for the preservation of health. He will then answer our prayer, if His name can be glorified thereby.”8 

God’s promises are sure. We can thank Him for allowing science to verify what Christians have known all along!

Next month: Part 3 of “Prayer in the Science Lab”

1. The research team assumed that most of the patients would be prayed for by friends and relatives; but only one group received additional prayers from outsiders.
2. This was so that no biases would affect the outcome of the study.
3. Byrd, MD, Randolph C., Southern Medical Journal, Volume 81, #7, July 1988.
4. Harris, PhD, William S., et al, Archives of Internal Medicine, October 25, 1999.
5. Matthews, D.A., et al, Southern Medical Journal, Volume 93, #12, December 2000.
6. Hodge, David R., Research on Social Work Practice, Volume 17, #2, March 2007.
7. See James 5:16.
8. White, Ellen, Counsels on Health, page 59.