title: Performance status of health care facilities changes with risk adjustment of HbA1c.
abstract: OBJECTIVE
  To develop a risk adjustment method for HbA1c, based solely on administrative data and to determine the extent to which risk-adjusted HbA1c changes the identification of high- or low-performing medical facilities.
  
  
  METHODS
  Through use of pharmacy records, 204,472 diabetic patients were identified for federal fiscal year 1996 (FY96). Complete information (HbA1c levels, demographic data, inpatient records, outpatient pharmacy utilization records) was available on 38,173 predominantly male patients from 48 Veterans Health Administration (VHA) medical facilities. Hierarchical mixed-effects models were used to estimate risk-adjusted unique facility-level HbA1c.
  
  
  RESULTS
  Predicted HbA1c demonstrated expected patterns for major factors known to influence glycemic control. Poorer glycemic control was seen in minorities and patients with greater disease severity, longer duration of disease (using treatment type or presence of amputation as surrogates), and more extensive comorbidity (measured by an adapted Charlson index). Better glycemic control was seen in Caucasians, older diabetic patients, and patients with higher outpatient utilization. The number of performance outliers was reduced as a result of risk adjustment. For mean HbA1c levels, 7 facilities that were initially identified as statistically significant outliers were no longer outliers after risk adjustment. For high-risk HbA1c (>9.5%) rates, 12 facilities that were initially identified as statistically significant outliers were no longer outliers after risk adjustment.
  
  
  CONCLUSIONS
  Risk adjustment using only administrative data resulted in substantial changes in identification of high or low performers compared with non-risk-adjusted HbA1c. Although our findings are exploratory, risk adjustment using administrative data may be a necessary and achievable step in quality assessment of diabetes care measured by rates of high-risk HbA1c (>9.5%).
authors.affiliation: Veterans Affairs Medical Center, East Orange, New Jersey 07018, USA.
authors.forename: Q
authors.initials: Q
authors.lastname: Zhang
authors.forename: M
authors.initials: M
authors.lastname: Safford
authors.forename: J
authors.initials: J
authors.lastname: Ottenweller
authors.forename: G
authors.initials: G
authors.lastname: Hawley
authors.forename: D
authors.initials: D
authors.lastname: Repke
authors.forename: J F
authors.initials: JF
authors.lastname: Burgess
authors.forename: S
authors.initials: S
authors.lastname: Dhar
authors.forename: H
authors.initials: H
authors.lastname: Cheng
authors.forename: H
authors.initials: H
authors.lastname: Naito
authors.forename: L M
authors.initials: LM
authors.lastname: Pogach
mesh_terms: D000328:Adult; D000368:Aged; D003695:Delivery of Health Care / Q000592:standards*; D003920:Diabetes Mellitus / Q000097:blood / Q000628:therapy*; D005006:Ethnicity; D005260:Female; D006442:Glycated Hemoglobin / Q000032:analysis*; D006787:Hospitals, Veterans / Q000592:standards; D006801:Humans; D008297:Male; D008499:Medical Records; D008875:Middle Aged; D016017:Odds Ratio; D010607:Pharmacy Service, Hospital; D018570:Risk Assessment; D014481:United States
chemical_list: D006442:Glycated Hemoglobin