Prayer’s power to heal is examined in a recent study entitled “Mantra II” conducted at Duke by a cardiologist. The experiment involved 748 patients who were treated for heart problems at nine hospitals around the nation. Contrary to several recent and oft-cited studies, in this the largest study of the phenomenon, there was no empirical evidence that prayer by strangers made any difference in outcomes:

The researchers enlisted 12 congregations of various Christian denominations, Jews, Muslims and Buddhists around the world to pray for some of the patients, giving them names, ages and descriptions of the illness. The researchers then divided the patients into four groups. The first quarter had people praying for them. The second quarter received a nontraditional treatment known as music, imagery and touch (MIT) therapy, which involved breathing techniques, soothing music, touch and other ways to relieve stress, such as calming mental images. The third group received both prayer and MIT, while the fourth received nothing.

In the final year of the study, the researchers took the additional step of asking more religious congregations to pray for the prayers of the initial group to work. Neither the patients nor their doctors knew whether someone was praying for them. The prayers varied depending on the religion, lasting between six and 30 days.

The researchers then followed all the patients for six months to see which patients suffered serious complications, were re-hospitalized or died from heart problems. Overall, there was no difference among the four groups, the researchers report in Saturday’s issue of the Lancet medical journal.