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Geographic and Provider Variations in Ocular Hypotensive Medication Claims Among Medicare Part D Enrollees
Timothy M Janetos1,2, Dustin D French1,3,4, Jennifer L Beaumont5
1Departments of Ophthalmology.
Purpose:
The purpose of this study was to describe the prescribing patterns of ocular hypotensive medications by ophthalmologists and optometrists in the United States for Medicare beneficiaries.
Materials And Methods:
This cross-sectional observational study examined all Medicare part D claims of ocular hypotensive medications prescribed by practicing ophthalmologists and optometrists in the United States in 2014. Claims rate was calculated as a function of the total number of Medicare part D beneficiaries within a given region. Claims rates were compared between ophthalmologists and optometrists and by region (state, and county level). The coefficient of variation was used to quantify treatment variation at the state level.
Results:
The rates of claims for prescriptions from ophthalmologists were higher nationally than from optometrists by a 6:1 ratio. Claims rates in urban, large and small rural cities were significantly greater for ophthalmologists. Claims rates associated with optometrists were greater in isolated small rural towns. The coefficient of variation at the state level was 52.0 for optometrists, 32.6 for ophthalmologists, and 25.2 for both groups combined.
Conclusions:
Medicare part D claims data for ocular hypotensive medications indicate ophthalmologists used a significantly wider range of medications, derived from more medication classes and treated more patients than optometrists. A larger proportion of ocular hypotensive medication claims were associated with ophthalmologists in urban and suburban regions. The opposite was observed in isolated small rural towns. At the state level, there is a large variation in medication claims rates with the highest rates in New York and Washington, DC.
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