NYTimes.com
WASHINGTON — Most medical devices have never been shown to be safe or effective, and for the riskiest devices this must change, Congressional investigators concluded in a report released Thursday. The Food and Drug Administration has promised for decades that it would fix the problem. It has not, leading the Government Accountability Office to state in the report that “it is imperative that F.D.A. take immediate steps” to fix its system for approving devices.