Changes in how medical diagnoses are coded under the latest international disease classification system - better known as the ICD-10 codes - may complicate the assessment of hospital safety, say researchers at the University of Illinois at Chicago. Their report is available online in the Journal of the American Medical Informatics Association (JAMIA).

Codes for diagnoses that serve as patient safety indicators may not translate in a simple way from ICD-9 to ICD-10, says Andrew Boyd, assistant professor of biomedical and health information sciences at UIC and first author of the paper.

For example, a hemorrhage coded in ICD-9 may have any of several different codes in ICD-10