The study is the first of its kind aimed at understanding "adverse events" in hospitals — essentially, any medical care that causes harm to a patient, according to the Department of Health and Human Services' Office of Inspector General.
Patients in the study, a nationally representative sample that focused on 780 Medicare patients discharged from hospitals in October 2008, suffered such problems as bed sores, infections and excessive bleeding from blood-thinning drugs, the report found. The federal Agency for Healthcare Research and Quality called the results "alarming."