A new report shows Indiana hospitals and ambulatory surgery centers recorded 94 preventable medical errors in 2009, a drop from the 105 mistakes reported in 2008 and 2007.

The most common error in the 2009 report was a foreign object such as a sponge left in a patient after surgery. Indiana's 306 facilities reported that error 29 times.

The report released Monday by the state Department of Health counted 17 instances of surgery performed on the wrong body part.

Pressure ulcers, or bed sores, occurred 22 times in 2009 — down from 33 the previous year.

The report from the Indiana Medical Error Reporting System credited the drop in bed sores to a statewide initiative focused on improving care for patients at risk for developing such sores.