Efficacy of prayer


What prayer does, if anything, is a question that has been addressed in various religious traditions and more recently in scientific studies. The question is complicated because there are myriad ideas about what prayer is, what functions prayer has, and what are expected outcomes of prayer. Moreover, while some religious groups argue that the "power of prayer" is obvious, others question whether it is possible to measure its effect. Basic philosophical issues inform the question as to whether prayer is efficacious, for example, whether statistical inference and falsifiability inform what it means to "prove" or "disprove" something, and the problem of demarcation, i.e., as to whether this topic is even within the realm of science at all.
Various scientific studies have addressed the topic of the efficacy of prayer at least since Francis Galton in 1872. According to the Washington Post, "...prayer is the most common complement to mainstream medicine, far outpacing acupuncture, herbs, vitamins and other alternative remedies". Medical studies on prayer have generally shown mixed results when it comes to the efficacy of prayer in recovery from illnesses. The largest study, from the 2006 STEP project, found no significant differences in patients recovering from heart surgery whether the patients were prayed for or not. The patients who knew they were receiving prayers did experience slightly higher recovery complications, possibly due to chance and to the added anxiety or pressure caused by expectations from the prayers. However, one of the authors of the study emphasized that this study did not say anything about the power of prayer itself. Fred Rosner and others have expressed doubt that prayer could ever be subject to empirical analysis.
Some studies on subjective well-being and personal effects of prayer have shown positive effects on the individual who prays.
Carefully monitored studies of prayer are relatively scarce with $5 million spent worldwide on such research each year.

Classes of studies

First person studies

An example of a study on meditative prayer was the Bernardi study in the British Medical Journal in 2001. It reported that by praying the rosary or reciting yoga mantras at specific rates, baroreflex sensitivity increased significantly in cardiovascular patients.
A study published in 2008 used Eysenck's dimensional model of personality based on neuroticism and psychoticism to assess the mental health of high school students based on their self-reported frequency of prayer. For students both in Catholic and Protestant schools, higher levels of prayer were associated with better mental health as measured by lower psychoticism scores. However, among pupils attending Catholic schools, higher levels of prayer were also associated with higher neuroticism scores.
Many accept that prayer can aid in recovery due to psychological and physical benefits. It has also been suggested that if a person knows that he or she is being prayed for it can be uplifting and increase morale, thus aiding recovery. Many studies have suggested that prayer can reduce physical stress, regardless of the god or gods a person prays to, and this may be true for many reasons. According to a study by CentraState Healthcare System, "the psychological benefits of prayer may help reduce stress and anxiety, promote a more positive outlook, and strengthen the will to live." Other practices such as Yoga, T'ai chi, and Meditation may also have a positive impact on physical and psychological health.
A 2001 study by Meisenhelder and Chandler analyzed data obtained from 1,421 Presbyterian pastors surveyed by mail and found that their self-reported frequency of prayer was well-correlated with their self-perception of health and vitality. This research methodology has inherent problems with self-selection, selection bias, and residual confounding, and the authors admitted that the direction of perceived prayer and health relationships "remains inconclusive due to the limits of the correlational research design".

Second person studies

One condition that may affect the efficacy of intercessory prayer is whether the person praying has a connection to the person prayed for. A 2005 study published by The Journal of Alternative and Complementary Medicine alleges evidence that eleven healers in a variety of "distant intentionality" modalities were able to remotely influence the MRI-measurable brain activity in chosen partners who were physically and electrically isolated. As the authors explained, "the study is not about healing per se, but whether there is some correlation in the intention to connect at a distance with a person." The experiment has not yet been reproduced by the authors or by others.

Third party studies

The Victorian scientist Francis Galton made the first statistical analysis of third-party prayer. He hypothesized, partly as satire, that if prayer was effective, members of the British Royal Family would live longer than average, given that thousands prayed for their well-being every Sunday, and he prayed over randomized plots of land to see if the plants would grow any faster, and found no correlation in either case.
The amount of formal research performed on intercessory prayer is quite small, with about $5 million spent worldwide on such research each year. The parameters used within the study designs have varied, for instance, daily or weekly prayers, whether to provide patient photographs, with full or partial names, measuring levels of belief in prayer, and whether patients underwent surgery.
The third party studies reported either null results, correlated results, or contradictory results in which beneficiaries of prayer had worsened health outcomes. For instance, a meta-analysis of several studies related to distant intercessory healing published in the Annals of Internal Medicine in 2000 looked at 2774 patients in 23 studies, and found that 13 studies showed statistically significant positive results, 9 studies showed no effect, and 1 study showed a negative result.
A 2003 levels of evidence review found evidence for the hypothesis that "Being prayed for improves physical recovery from acute illness". It concluded that although "a number of studies" have tested this hypothesis, "only three have sufficient rigor for review here". In all three, "the strongest findings were for the variables that were evaluated most subjectively, raising concerns about the possible inadvertent unmasking of the outcomes' assessors. Other meta-studies of the broader literature have been performed showing evidence only for no effect or a potentially small effect. For instance, a 2006 meta analysis on 14 studies concluded that there is "no discernible effect" while a 2007 systemic review of intercessory prayer reported inconclusive results, noting that 7 of 17 studies had "small, but significant, effect sizes" but the review noted that the three most methodologically rigorous studies failed to produce significant findings.

Secondary, inter-personal effects

Apart from whether prayer affects other beneficiaries, research has suggested that prayer has benefits on the person performing the prayer, e.g. in May 2011 a study was conducted that suggested a "significant specific indirect effect" between meditative prayer and hope, adult attachment, and forgiveness. Research has also suggested that prayer has a direct relation to a sense of overall gratitude in life. Prayer may also aid those dealing with alcoholism, e.g. a 2010 study suggested that there is a strong correlation between prayer and reduction of alcohol consumption. Those who actively pray during the week reported half as many consumed alcoholic drinks.
An increasingly more researched area within psychology of religion has been the relational implications of prayer, e.g. a study in 2011 conducted by Lambert et al. stated that when compared to a control group that experienced positive interactions with their significant other those in the prayer condition reported much higher feelings of unity and trust toward their significant other. Studies have also shown that there are increased feelings of marital enrichment through prayer. A study conducted in 2010 has also shown a correlation between prayer within relationships and reduction of infidelity. As with other areas of research about prayer, some debate whether these effects are a result of the prayer or a "placebo effect." However, Dr. Herbert Benson, a professor of medicine at Harvard Medical School, suggests that they may not be mutually exclusive.

Belief and skepticism

Medical views

Virtually all scientists dismiss faith healing as pseudoscience. Some opponents of the pseudoscience label assert that faith healing makes no scientific claims and thus should be treated as a matter of faith that is not testable by science. Critics reply that claims of medical cures should be tested scientifically because, although faith in the supernatural is not in itself usually considered to be the purview of science, claims of reproducible effects are nevertheless subject to scientific investigation.
Scientists and doctors generally find that faith healing lacks biological plausibility or epistemic warrant, which is one of the criteria to used to judge whether clinical research is ethical and financially justified. A Cochrane review of intercessory prayer found "although some of the results of individual studies suggest a positive effect of intercessory prayer, the majority do not". The authors concluded: "We are not convinced that further trials of this intervention should be undertaken and would prefer to see any resources available for such a trial used to investigate other questions in health care".
An article in the Medical Journal of Australia says that "One common criticism of prayer research is that prayer has become a popular therapeutic method for which there is no known plausible mechanism."
Medical professionals are skeptical of new claims by studies until they have been experimentally reproduced and corroborated. For instance, a 2001 study by researchers associated with Columbia University has been associated with controversy, following claims of success in the popular media.
Although different medical studies have been at odds with one another, physicians have not stopped studying prayer. This may be partly because prayer is increasingly used as a coping mechanism for patients.

Skepticism on scope of prayer

In a debate/interview in Newsweek with Christian evangelical Rick Warren, atheist Sam Harris commented that most lay perceptions of the efficacy of prayer were related to sampling error because "we know that humans have a terrible sense of probability." That is, humans are more inclined to recognize confirmations of their faith than they are to recognize disconfirmations.
Harris also criticized existing empirical studies for limiting themselves to prayers for relatively unmiraculous events, such as recovery from heart surgery. He suggested a simple experiment to settle the issue:
Get a billion Christians to pray for a single amputee. Get them to pray that God regrow that missing limb. This happens to salamanders every day, presumably without prayer; this is within the capacity of God. I find it interesting that people of faith only tend to pray for conditions that are self-limiting.

Within Christian teachings, the comment by Harris regarding what he called the self-limiting nature of prayer had been addressed years before by multiple authors. For instance, in the 19th century William Peabody discussed the efficacy of prayer in the face of what he called the immutability of the laws of nature. He said:

Night follows day, and day night. The seasons preserve their succession... We may not hope to suspend their operation by our prayers... And yet notwithstanding all of this, we hold in an undoubting faith the doctrine of the efficacy of our prayers, or to use the language of another, "of an influence from above as diversified and unceasing as are the requests from below".

Peabody then argued at length that prayers may have efficacy in a form that does not interfere with the arrangement of the laws of nature, and that God may respond in ways that are not anticipated, without changing the arrangement of nature. George Burnap echoed the same concept when he wrote:

God governs the universe by fixed and uniform laws, not only for the sake of order, but for
human good... The fulfillment of every human desire would break up this order, and
bring everything into disorder and confusion.

Prayers and miracles

The view expressed by Harris above regarding the "relatively unmiraculous" petitions used in prayers has been addressed in religious circles in the context of miraculous outcomes for prayer. There are different theological classifications of miracles, one of the most common being the three categories: "surpassing nature", "against nature" and "alongside nature".
The raising of the dead is considered a "supra naturam" event and is not reported in theological writings beyond the Christian Bible, where ten resurrection events are recorded. Contra naturam events require significant changes to the "order of the world" and are also hardly ever reported. Praeter naturam events can proceed along the laws of nature. They have been reported in a number of cases, and have been subject to a large amount of debate. Examples include the claims of miraculous cures at pilgrimage site such as Our Lady of Lourdes. Many of these claims have been analyzed and only a few have been accepted by the Lourdes Medical Bureau.

Massive prayer

The scientific measurement of the efficacy of massive prayer requires the coordination of the activities of a large number of people, and no direct citations for the existence of such studies appear in the scientific literature. However, non-scientific instructions for massive prayer have been issued in the past, and conclusions about the effects of the prayer have been drawn by a large number of believers, outside a scientific framework.
In a historical context, in 1571 Pope Pius V called for all of Europe to pray the Rosary for victory at the Battle of Lepanto, in which the Christian belligerents included the Papal States. Trophies from the battle are now enshrined in various Christian churches which attribute the victory to the massive prayers.
Directions for even more massive, long term prayers were provided by the messages of Our Lady of Fatima reported by Lucia Santos, who stated that the Virgin Mary specifically asked believers to pray for the conversion of Russia. The 9-day Fatima Novena prayer includes a petition for the conversion of Russia. With a blessing from Pope Pius XII millions of members of the Blue Army of Our Lady of Fatima were instructed to pray for several years in publications such as Soul Magazine. Some Christians attribute the fall of communism in the Revolutions of 1989 to massive prayers, while economists attribute them to market forces and socioeconomic conditions.

Religious and philosophical issues

Religious and philosophical objections to the very study of prayer's efficacy exist. Many interpret Deuteronomy to mean that prayer cannot, or should not, be examined.
The religious viewpoint objects to the claim that prayer is susceptible to experimental designs or statistical analysis, and other assumptions in many experiments, e.g. that a thousand prayers are statistically different from one. The objections also include the complaint that religion generally deals with unique, uncontrollable events; statistics, and science in general, deal with recurring phenomena which are possible to sample or control and are susceptible to general laws.
Religious objections also include the complaint that as prayer starts to be measured, it is no longer real prayer once it gets involved in an experiment and that the concept of conducting prayer experiments reflects a misunderstanding of the purpose of prayer. The 2006 STEP experiment indicated that some of the intercessors who took part in it complained about the scripted nature of the prayers that were imposed to them, saying that this is not the way they usually conduct prayer:
With respect to expectation of a response to prayer, the 18th-century philosopher William Paley wrote:

To pray for particular favors is to dictate to Divine Wisdom, and savors of presumption; and to intercede for other individuals or for nations, is to presume that their happiness depends upon our choice, and that the prosperity of communities hangs upon our interest.

During the 20th-century, philosopher Bertrand Russell believed that religion and science "have long been at war, claiming for themselves the same territory, ideas and allegiances". And Russell believed that the war had been decisively won
by science. Almost 40 years earlier, a 22-year-old Russell also wrote: "For although I had long ceased to believe in the efficacy of prayer, I was so lonely and so in need of some supporter such as the Christian God, that I took to saying prayers again when I ceased to believe in their efficacy."
The 21st-century evolutionary biologist Richard Dawkins, describing how Richard Swinburne explained away the STEP experiment's negative results "on the grounds that God answers prayers only if they are offered up for good reasons", says that some elements of religion are testable.
Other theologians joined NOMA-inspired sceptics in contending that studying prayer in this way is a waste of money because supernatural influences are by definition beyond the reach of science. But as the Templeton Foundation correctly recognized when it financed the study, the alleged power of intercessory prayer is at least in principle within the reach of science. A double-blind experiment can be done and was done. It could have yielded a positive result. And if it had, can you imagine that a single religious apologist would have dismissed it on the grounds that scientific research has no bearing on religious matters? Of course not.

The Holy Spirit and Christian teaching

Some Christian authors have contended for long that the efficacy of prayer involves the action of the Holy Spirit, e.g. referring to the Gospel of Luke,
John Tillotson, the 17th-century Archbishop of Canterbury argued that the efficacy of prayer depends on the Holy Spirit. Reformed Presbyterian scholar Wayne R. Spear argues that the person praying needs to be "guided by the Holy Spirit" as to what needs to be prayed for and that given the "right petition" the Holy Spirit will then intercede for the prayer.
The Catechism of the Catholic Church states that:
Christian existentialist philosopher and theologian Paul Tillich argued that prayer is not possible in a subject–object dichotomy in which the person is separated from God, for God cannot be the object of a prayer without being at the same time the subject.