Is there any evidence that running shoes prevent running injuries?

I am interested in finding out whether standard running shoes (elevated cushioned heel, motion control systems) reduce your risk of getting injured running. I have been searching the literature to try and find any controlled trials which directly measured the effect of these shoes on musculoskeletal injury rates. I am cynical about marketing at the best of times, but even I was surprised that I couldn't find any direct evidence that these shoes do in fact prevent injuries. Is anyone aware of any studies I may have missed, or is the running shoe market all just a big scam?