Systematic review of clinical trials examining the effects of religion on health. (Review Article)

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Authors: Mark Townsend, Virginia Kladder, Hana Ayele and Thomas Mulligan
Date: Dec. 2002
From: Southern Medical Journal(Vol. 95, Issue 12)
Publisher: Southern Medical Association
Document Type: Article
Length: 4,149 words

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ABSTRACT: Using MEDLINE, (limited to the English language and the reference lists of the randomized controlled trials (RCTs), we assessed the impact of religion on health outcomes via systematic, critical review of the medical literature. All RCTs published from 1966 to 1999 and all non-RCTs published from 1996 to 1999 that assessed a relationship between religion and measurable health outcome were examined. We excluded studies dealing with nonreligious spirituality, ethical issues, coping, well-being, or life satisfaction. We used the Canadian Medical Association Journal's guidelines for systematic review of the medical literature to evaluate each manuscript. Nine RCTs and 25 non-RCTs met these inclusion/exclusion criteria. Randomized controlled trials showed that intercessory prayer may improve health outcomes in patients admitted to a coronary care unit but showed no effect on alcohol abuse. Islamic-based psychotherapy speeds recovery from anxiety and depression in Muslims. Non-RCTs indicate that religious activities appear to benefit blood pressure, immune function, depression, and mortality.


RELIGION is a source of comfort to some and conflict to others. The vast majority of Americans (94%) claim to believe in God. (1) Among older Americans, 98% believe in God, and 95% pray regularly. (2) However, physicians tend to ignore religious issues in the care of their patients, (3) and the majority of scientists reject any belief in God. (4)

In published medical literature, there is similar conflict. Sloan et al (5) reviewed the literature and found inconsistent and weak links between religion and health. In contrast, the reviews by Levin and Schiller (6) and by Larson et al (7) identified generally positive effects of religion on physical and mental health, leading some authors to call for a revival in the soul of health care. (8)

Given this conflict, we conducted a systematic, critical review of the medical literature. We focused on rigorously designed studies--ie, randomized controlled trials (RCTs). To avoid missing potentially important scientific investigations that used less rigorous designs, we also reviewed recently published cross-sectional or other studies assessing the interaction (positive or negative) between religion and health.


Our goal was to assess the impact (positive or negative) of religion on health outcomes. We used standard definitions of religion. Webster's dictionary defines religion as, "a set of beliefs concerning the cause, nature and purpose of the universe ... usually involving devotional and ritual observances, and often containing a moral code for the conduct of human affairs. A specific fundamental set of beliefs and practices generally agreed upon by a number of persons or sects." (9) For the purposes of this review, we accepted any reproducible measure of religion in accordance with that definition. Importantly, however, we did not assess spirituality. Spirituality was excluded because it is a set of "personal views and behaviors that express a sense of relatedness to the transcendental dimension or to something greater than the self" (10) Therefore, we reviewed such activities as prayer or church attendance but not seances.

Health outcome was defined as any outcome that can be quantitated by reproducible, universally accepted, and established...

Source Citation

Source Citation
Townsend, Mark, et al. "Systematic review of clinical trials examining the effects of religion on health. (Review Article)." Southern Medical Journal, vol. 95, no. 12, Dec. 2002, pp. 1429+. Accessed 28 Nov. 2022.

Gale Document Number: GALE|A98033290