STEP Study: Largest Randomized Prayer Trial Finds No Benefit — and a Backfire Effect
It happened — and nature accounts for it.
The account
The 2006 Study of the Therapeutic Effects of Intercessory Prayer, the largest and best-controlled trial of its kind, found no statistically significant benefit from prayer for cardiac bypass patients and observed a slight increase in complications among patients who knew they were being prayed for.
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The Study of the Therapeutic Effects of Intercessory Prayer — known as STEP — enrolled 1,802 cardiac bypass surgery patients across six US hospitals between 1998 and 2000. Harvard cardiologist Herbert Benson led the study. The Templeton Foundation was a partial funder.
Patients were assigned to one of three groups: receive prayer without knowing it, receive no prayer without knowing it, or receive prayer and be told so. Three established Christian prayer groups interceded on behalf of those assigned to receive prayer, beginning the night before surgery and continuing for two weeks. The prayer groups were St. Paul's Monastery in Minnesota, the Community of Teresian Carmelites, and Silent Unity in Missouri. The outcome measure was any major complication or death within 30 days.
The results were published in the American Heart Journal in April 2006. There was no statistically significant difference between the prayed-for (unaware) group and the not-prayed-for group. The group told they were being prayed for had a higher complication rate — 59% compared to 51-52% in the other groups. Researchers attributed this difference to the psychological burden of knowing strangers were interceding on their behalf, described as performance anxiety or expectation pressure.
Reviewer Notes
We weigh a claim on two things, kept separate from the story above.
Assessed by Miracles Jar AI
No benefit from intercessory prayer; knowing you are prayed for slightly increased complications.
The verdict: No benefit from intercessory prayer; knowing you are prayed for slightly increased complications.
The study is the largest randomized controlled trial of therapeutic intercessory prayer ever conducted. It enrolled patients from 1998–2000 across six US hospitals and was published in 2006 in the American Heart Journal (PMID 16569567). Three independent Christian prayer groups participated, with diversity of practice strengthening the null finding. The primary endpoint showed no statistically significant difference. The complication rate was 59% in patients who knew they were being prayed for, versus 51–52% in the other groups.
The Templeton Foundation partially funded the study and had every reason to want a positive result. It did not get one. The null finding has not been overturned by any subsequent study.
The absence of a significant difference between the two unaware groups falsifies the efficacy hypothesis under the study's design. The elevated complication rate in the group that knew they were being prayed for is not supernatural backlash — the most plausible explanation is that being told you are the subject of a prayer study may have increased procedural anxiety.
Sources: Benson H et al., "Study of the Therapeutic Effects of Intercessory Prayer (STEP) in cardiac bypass patients: a multicenter randomized trial," American Heart Journal, 2006, PMID 16569567; "Prayers don't help heart surgery patients," Harvard Gazette, 2006.
Evidence ledger — what the verdict rests on
No significant difference in 30-day complication rates between prayed-for (unknown) and not-prayed-for groups
Primary endpoint of the study; p-value not significant
Group told they were being prayed for had 59% complication rate vs 51-52% for the other groups
Interpreted as performance anxiety or expectation burden, not supernatural backlash
Three independent Christian prayer groups interceded; the diversity of practice strengthens the null finding
St. Paul's Monastery MN, Community of Teresian Carmelites, Silent Unity MO
Study was partly funded by the Templeton Foundation, which had financial interest in a positive result
Methodological credibility enhanced by funder's incentive structure running against result
What would raise this score: Long-term follow-up documenting permanence, in a condition with a near-zero spontaneous-resolution base rate, would raise the meter.
What would lower it: A documented relapse, or case literature showing the condition fluctuates or remits on its own, would move it down.
How this works
We keep two questions apart on purpose — so a thin record can’t make an impossible thing look proven, and a strong record can’t dress up an ordinary one as a miracle. First: Could nature explain it? (taking the account as true for the moment.) The question is whether nature could produce this at all — assuming, for the moment, the events are true as described. Second: is there real evidence it happened? A claim only stands out when both hold up — and we never call anything certain either way. How ratings work →
The natural explanation
The leading natural account for this case is spontaneous remission & the body's own recovery. Read what it explains — and where it stops.
Sources
Tagged by proximity to the event. Primary sources are direct or contemporaneous; tertiary are downstream retellings.
- 1.Primaryacademic
Benson H et al., "Study of the Therapeutic Effects of Intercessory Prayer (STEP) in cardiac bypass patients: a multicenter randomized trial", 2006· no public link
Published in American Heart Journal; establishes null/negative result in 1,802-patient trial
- 2.Secondarynews
"Prayers don't help heart surgery patients — Harvard Gazette", 2006· no public link
Harvard press office summary; notes Templeton funding and backfire result
- 3.Primaryacademic
"PubMed abstract PMID 16569567", 2006· no public link
Peer-reviewed record; full citation available
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