As many as 195,000 people a year could be dying in U.S. hospitals because of easily prevented errors, a company said on Tuesday in an estimate that doubles previous figures.

Lakewood, Colorado-based HealthGrades Inc. said its data covers all 50 states and is more up-to-date than a 1999 study from the Institute of Medicine that said 98,000 people a year die from medical errors.

“The HealthGrades study shows that the IOM report may have underestimated the number of deaths due to medical errors, and, moreover, that there is little evidence that patient safety has improved in the last five years,” said Dr. Samantha Collier, vice president of medical affairs at the company.

The company, which rates hospitals based on a variety of criteria and provides information to insurers and health plans, said its researchers looked at three years of Medicare data in all 50 states and Washington, D.C.

“This Medicare population represented approximately 45 percent of all hospital admissions (excluding obstetric patients) in the U.S. from 2000 to 2002,” the company said in a statement.

HealthGrades included as mistakes failure to rescue dying patients and the death of low-risk patients from infections - neither of which the Institute of Medicine report included.

It said it found about 1.14 million “patient-safety incidents” occurred among the 37 million hospitalizations.

“Of the total 323,993 deaths among Medicare patients in those years who developed one or more patient-safety incidents, 263,864, or 81 percent, of these deaths were directly attributable to the incidents,” it added.

“One in every four Medicare patients who were hospitalized from 2000 to 2002 and experienced a patient-safety incident died.”

The U.S. government said it is trying to spearhead a move to get hospitals and clinics to use electronic databases and prescribing methods. The Institute of Medicine report said many deaths were due to medication prescribing errors or to errors in delivering medications.

“If the Centers for Disease Control and Prevention’s annual list of leading causes of death included medical errors, it would show up as number six, ahead of diabetes, pneumonia, Alzheimer’s disease and renal disease,” Collier said.