They rate institutions on their ability to avoid errors, accidents, injuries and infections and receive guidance from the Johns Hopkins Armstrong Institute for Patient Safety and Quality.
Rush University Medical Center's B grade was partly due to errors in hospital claims data, Dr. Omar Lateef, CEO of Rush University Medical Center, as well as the chief medical officer of the hospital and the health system, said in a statement.
"Hospitals that earn an "A" grade are making it a priority to protect patients from preventable medical harm and error".
Developed under the guidance of a National Expert Panel, the Leapfrog Hospital Safety Grade uses 28 measures of publicly available hospital safety data to assign grades to more than 2,600 US acute-care hospitals twice per year.
"So it really matters which hospital people choose, which is the objective of our Hospital Safety Grade", Binder said.
There are five hospitals in IL that have maintained A grades for the past 7 years, which is how long the report has been around, including two owned by Northwestern and Rush.
UP Health System-Portage in Hancock received an "A" - one of 26 hospitals in MI to get the top rating.
The only hospital receiving an F was Hurley Medical Center, a 443-bed public hospital in Flint.
"Hurley Medical Center is a repeat offender in delivering the poorest patient safety in the state".
Hurley is committed to patient safety as a continuous goal and regularly evaluates best practices to improve patient care, Laura Jasso, Hurley's marketing and community relations administrator, told Crain's.
An estimated 161,250 preventable deaths occur each year in USA hospitals, a decline from three years ago, according to a new analysis from the Leapfrog Group.
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"If every hospital had the performance of an "A" hospital, an estimated 50,000 lives saved could be saved", according to Leapfrog.
"Avoidable medical errors and infections in hospitals continue to be one of the leading causes of death in the US", said Leah Binder, president and CEO of The Leapfrog Group, in a press release.
"We appreciate the ongoing efforts by Leapfrog to improve the usefulness and accessibility of information for consumers", Megan McCann, a spokeswoman for the hospital, said in an email.
The Leapfrog Hospital Safety Grades are an independent, nonprofit grading system administered on behalf of employers and other purchasers of healthcare services.