Small area variation in endoscopic sinus surgery rates among the Medicare population.

Objectives: To determine endoscopic sinus surgery (ESS) rates among 306 hospital referral regions (HRRs) and to assess whether variability in ESS rates correlates with population density of beneficiaries, per capita number of otolaryngologists within an HRR, or proportion of patients diagnosed as having chronic rhinosinusitis.

Design: Retrospective cohort analysis.

Setting: Academic research.

Patients: A 20% sample of Medicare beneficiaries aged 65 to 99 years diagnosed as having chronic rhinosinusitis and undergoing ESS in 2006.

Main Outcome Measures: Variation in per capita rates of chronic rhinosinusitis diagnosis and ESS in 2006.

Results: Among 306 HRRs nationally, ESS was performed in sufficient volume to be reported in 148 HRRs. Per capita ESS rates (sinus surgical procedures per 1000 beneficiaries) varied 5-fold, from 0.02 to 0.10, with significant variations within states. Nationally, no geographic or regional patterns were noted, and high-use HRRs were often geographically proximal to low-use HRRs. Higher rates of chronic rhinosinusitis diagnosis and more beneficiaries in particular HRRs did not predict increased ESS within the HRRs.

Conclusions: Local ESS rates in the Medicare population vary considerably across the United States. Variability in high-use vs low-use regions seems to be random and independent of climate or the number of beneficiaries diagnosed as having chronic rhinosinusitis. Given that the appropriate rate of sinus surgery is unknown, this study points to the need for identifying and adopting more rigorous clinical criteria for ESS.