CHICAGO -- More than 40 potentially harmful drug errors daily were found on average in hospitals in a new study, yet another report on a worrisome problem regulators are working to remedy.

The most common errors were giving hospitalized patients medication at the wrong time or not at all, researchers found in a study of 36 hospitals and nursing homes in Colorado and Georgia.

Errors occurred in nearly one of five doses in a typical, 300-bed hospital, which translates to about two errors per patient daily. Seven percent of the errors were considered potentially harmful.

The study, which did not evaluate death or injury rates, is published in Sept. 9th's Archives of Internal Medicine. It is based on data collected in 1999.

The rates are similar to those in other reports on drug errors, but the new study highlights a specific point in the process of getting a drug to a patient: "administering errors" made by nurses or other hospital staffers after a doctor has properly prescribed a drug.

Other studies focused on earlier steps, such as doctors prescribing the wrong drug, or pharmacists incorrectly reading a doctor's messy handwriting.

"It's a major problem, not a minor problem, and it doesn't lend itself to an easy solution," said researcher Kenneth Barker, an Auburn University professor of pharmacy care systems.

Barker and colleagues evaluated hospitals accredited by the Joint Commission on Accreditation of Healthcare Organizations, nonaccredited hospitals and nursing facilities. Error rates were similar, regardless of whether an institution was accredited.

'Major' problems

The researchers said their findings support implications in a highly publicized 1999 Institute of Medicine report suggesting that the nation's hospitals have "major systems problems." The IOM report said medical errors contribute to more than 1 million injuries and up to 98,000 deaths annually.

Health care workers trained for the new study were sent on-site and recorded errors during 81 days of observation. Potentially harmful errors included overdoses and instances when nurses failed to give patients prescribed medication.

The study follows the Joint Commission's recent announcement of six safety standards it will require starting in January to reduce medical errors. The hospital regulatory agency accredits most of the nation's 6,000 hospitals.

The new standards include demanding better methods of preventing drug errors, and hospitals that don't measure up could risk losing accreditation and federal money.