NIS database used for hospital reimbursement contains major flaws

Editor's Note

The Nationwide Inpatient Sample (NIS) database underreports data on patients’ weight, body mass, alcohol use, and tobacco use, finds a study from the Johns Hopkins University School of Medicine, Baltimore. Medicare uses NIS data to set reimbursement rates based on a hospital’s risk for readmissions and surgical complications.

The researchers found the underreporting when they compared NIS with Behavioral Risk Factor Surveillance System (BRFSS) data—a federally sponsored telephone survey of more than 500,000 adults about their health.

The prevalence of obesity, overweight, tobacco smoking, and alcohol abuse based on codes is not consistent with prevalence gleaned from direct questioning. The accuracy of these health and morbidity measures in databases is crucial for healthcare reform policies, the authors note.

Background The lack of adequate and standardized recording of leading risk factors for morbidity and mortality in medical records have downstream effects on research based on administrative databases. The measurement of healthcare is increasingly based on risk-adjusted outcomes derived from coded comorbidities in these databases.