Adjusting for Patient Characteristics When Analyzing Reports From Patients About Hospital Care

The impact of adjusting for patient characteristics on hospital rankings was small, although a larger impact would be expected when comparing hospitals with more variability in types of patients. Nevertheless, we recommend adjusting at least for the most important predictors, such as age and health status. Such adjustment helps alleviate concerns about bias. It also may be useful to present data for certain groups of patients (ie, medical, surgical, obstetric) separately to facilitate interpretation and quality improvement efforts.