Are you aware of any statistical evidence for the benefits of prayer?

Assuming that most Christians would pray for help in time of need, is there any statistical evidence for better outcomes among Christians compared to other groups? For example, a Christian would presumably likely be praying to get well, get healthy, be happy, get a better job, pray for a sound marriage, etc. Yes, I know they would pray for other things too, but I'm asking about things that can be measured in statistics, mortuary tables, etc. I've just looked at a Pew Research study **Religion’s Relationship to Happiness, Civic Engagement and Health Around the World** which suggests perhaps better civic participation, but > after adjusting for differences in age, education, income and other factors, there is no statistical link between being actively religious and being in better self-reported overall health in any of the 26 countries and territories studied except Taiwan, Mexico and the United States. > >Even in the U.S., the strength of the linkage between religion and health varies, depending on measures and datasets used. For example, in some years, the General Social Survey has shown that religiously affiliated people who go to church or other religious services at least once a month are particularly likely to report that they are in excellent overall health, while in other recent years this has not been the case.