The Null Result, and the Finding Nobody Wanted

Prayer made no difference. Complication rates in the group prayed for and the group not prayed for, both uncertain of their status, were effectively identical. The unexpected part was the third arm: patients told with certainty that they were being prayed for had a somewhat higher complication rate than those left uncertain. The investigators declined to interpret this causally, and were right to. It is one comparison in one trial, it was not the primary hypothesis, and the plausible explanations, from performance anxiety to the possibility that being singled out signals a worse prognosis, are speculation. The trial is nonetheless the most useful entry in the intercessory prayer literature because of how it was built rather than what it found. Byrd in 1988 and Harris in 1999 had both reported positive effects using composite outcome measures assembled from many individual endpoints, a technique that generates apparent effects readily.

A Cochrane review of the field concluded that the accumulated trials did not justify further work of this kind. There is also a theological objection, made from inside religious traditions rather than against them, that a controlled trial treats petition as a mechanism to be metered, which is not what most of those traditions take prayer to be.