Different methods to determine mortality rate produce vastly different results

Patient Safety Monitor Insider

December 29, 2010

Whether or not a hospital gives quality care is often measured by mortality rate, but different ways of determining that rate can greatly affect the result, according to a recent New England Journal of Medicine study.

Four common methods for determining mortality rates were tested at acute-care Massachusetts hospitals from 2004 to 2007. The different methods produced substantially different results. The biggest variable is which patients—and how many—are included in analysis. Different methods sometimes led to "completely discordant impressions about relative hospital performance," concluded the authors of the study, something of concern as state and national mandates urge financial incentives based on such metrics.

Source: New England Journal of Medicine.