Abstract
BACKGROUND AND OBJECTIVES: Geographic and other variations in medical practices lead to differences in medical costs, often without a clear link to health outcomes. This work examined variation in the frequency of physician visits to patients receiving hemodialysis to measure the relative importance of provider practice patterns (including those patterns linked to geographic region) and patient health in determining visit frequency. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: This work analyzed a nationally representative 2006 database of patients receiving hemodialysis in the United States. A variation decomposition analysis of the relative importance of facility, geographic region, and patient characteristics--including demographics, socioeconomic status, and indicators of health status--in explaining physician visit frequency variation was conducted. Finally, the associations between facility, geographic and patient characteristics, and provider visit frequency were measured using multivariable regression. RESULTS: Patient characteristics accounted for only 0.9% of the total visit frequency variation. Accounting for case-mix differences, patients' hemodialysis facilities explained about 24.9% of visit frequency variation, of which 9.3% was explained by geographic region. Visit frequency was more closely associated with many facility and geographic characteristics than indicators of health status. More recent dialysis initiation and recent hospitalization were associated with decreased visit frequency. CONCLUSIONS: In hemodialysis, provider visit frequency depends more on geography and facility location and characteristics than patients' health status or acuity of illness. The magnitude of variation unrelated to patient health suggests that provider visit frequency practices do not reflect optimal management of patients on dialysis.