The studies did not cover the effect of being prayed for or by the usefulness of attending religious meetings.
Findings show that praying, measured by frequency, is usually associated with lower levels of depression and anxiety.
However most of the studies showing positive associations were in areas with strong Christian traditions and involved samples with strong religious beliefs.
Church attenders, older people, women, poor people and those with lower education levels were more likely to pray, researchers found.
Authors wrote: ‘There is no evidence that praying is likely to be beneficial in the absence of any kind of faith and some evidence that certain types of prayer based on desperate pleas for help in the absence of faith are associated with poorer wellbeing and function.
‘To reduce response bias, we suggest that future research should focus on a range of coping strategies that include prayer and other religious coping strategies, rather than focusing specifically on these. At the same time, studies need to distinguish between the effects of different types of prayer.’
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