Table 2: Hypothesis 1: Private Prayer is associated with better health outcomes.

StudySampleCohort followupPredictorOutcomeResultsNewcastle-Otawa grade

Ai et al. [25]177 patients undergoing CABG±3 weeksPrayer frequenciesPostoperative complications and hospitalizationPrayer frequencies were associated with reduced complications but not hospitalization8

Ai et al. [25]294 patients following open-heart surgery± 4-5 weeksPrivate prayerQuality of lifeIndirect influence of using prayer for coping on quality of life through the mediation of cognitive coping and perceived social support8

Ai et al. [27]310 patients following open-heart surgery± 4-5 weeksPrayer copingPreoperative stress symptomsPrayer coping was inversely related to preoperative stress symptoms7

Braam et al. [30]2 assessment cycles: and 3 yearsPrayer frequenciesChange in depressive symptomsAt three-year followup, prayer did not predict change of depressive symptoms7

Ai et al. [26]246 patients awaiting cardiac surgery2 weeksBelief in the importance of private prayerOptimismPrivate prayer predicted optimism, along with older age, better socioeconomic resources, and healthier affect7

Ai et al. [28]151 older patients following CABG1 yearPray about their postoperative problems and private prayerDepression and general distressMost patients pray about their postoperative problems and that private prayer appears to significantly decrease depression and general distress one year post-CABG8

CABG: coronary artery bypass graft surgery.