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Updated: Jan 30, 2026

Proper Care and Cleaning of the Microscope
Published on: August 11, 2008
Claims data analyses unable to properly characterize the value of neurologists in epilepsy care
Chloe E Hill1, Chun Chieh Lin2, James F Burke2
1From the Health Services Research Program (C.E.H., C.C.L., J.F.B., K.A.K., L.E.S., B.C.C.), Department of Neurology, University of Michigan, Ann Arbor; Department of Neurology (G.J.E.), Emory University, Atlanta, GA; and American Academy of Neurology (B.M.), Minneapolis, MN. chloehi@med.umich.edu.
Objective:
To determine the association of a neurologist visit with health care use and cost outcomes for patients with incident epilepsy.
Methods:
Using health care claims data for individuals insured by United Healthcare from 2001 to 2016, we identified patients with incident epilepsy. The population was defined by an epilepsy/convulsion diagnosis code (ICD codes 345.xx/780.3x, G40.xx/R56.xx), an antiepileptic prescription filled within the succeeding 2 years, and neither criterion met in the 2 preceding years. Cases were defined as patients who had a neurologist encounter for epilepsy within 1 year after an incident diagnosis; a control cohort was constructed with propensity score matching. Primary outcomes were emergency room (ER) visits and hospitalizations for epilepsy. Secondary outcomes included measures of cost (epilepsy related, not epilepsy related, and antiepileptic drugs) and care escalation (including EEG evaluation and epilepsy surgery).
Results:
After participant identification and propensity score matching, there were 3,400 cases and 3,400 controls. Epilepsy-related ER visits were more likely for cases than controls (year 1: 5.9% vs 2.3%, p < 0.001), as were hospitalizations (year 1: 2.1% vs 0.7%, p < 0.001). Total medical costs for epilepsy care, nonepilepsy care, and antiepileptic drugs were greater for cases (p ≤ 0.001). EEG evaluation and epilepsy surgery occurred more commonly for cases (p ≤ 0.001).
Conclusions:
Patients with epilepsy who visited a neurologist had greater subsequent health care use, medical costs, and care escalation than controls. This comparison using administrative claims is plausibly confounded by case disease severity, as suggested by higher nonepilepsy care costs. Linking patient-centered outcomes to claims data may provide the clinical resolution to assess care value within a heterogeneous population.
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