I can recall years ago a work collegue told of his wife dying of cancer.
I said nothing but decided to fast and pray for 3 days about it, I didn't know this woman, never met her.
Anyhow just prior to her death she became a christian which surprised me as he wasn't a christian. I never went to the funeral but it was in a church somewhere and apparently from what I was told it was a happy funeral.
Prayer may work, but I've heard lots of horror stories of christians going through a lot of terror and pain too, including nasty accidents.
These days I dont think too much about praying, we make our own luck, good or bad frequently.
I think maybe our minds pray for us.
Today I mentioned how one of my penny stocks went belly up to the tune of $12k. Well no big deal, I'm seasoned to huge swings as I don't trade pocket money, but coincidently today thanks largely to my gold holdings among other stuff I trade, I was up only $500 short of $12k at close. Prayer? Don't think so as it never entered my mind to pray because as mentioned was no big deal, but when I told wifey her mouth dropped until I told her I made it back again in the same day bar the 500 smackers.
Prolly everyone prays at times maybe, but as for results, prolly 50/50.