While addressing the “treatment gap,” the study by Kalilani et al differs from previous studies by evaluating patient cohorts with treatment delays after diagnosis of epilepsy. Therefore, the study provides important data about implementation of treatment after diagnosis. Kalilani et al analyzed 3 administrative databases, which contained millions of individuals, to identify patients with newly diagnosed epilepsy. They included patients who had an index date (the date of their first epilepsy diagnosis) with a preceding 2 years baseline within the database (1 year for ages 1 to <2 years; none for ages <1 year). To identify newly diagnosed patients, the investigators established a baseline definition of epilepsy diagnosis as any of the following criteria: (1) two ICD-9-CM (International Classification of Diseases, Ninth Revision, Clinical Modification) 345.xx (epilepsy and recurrent seizures) codes at separate encounters; (2) 1 ICD-9-CM 345.xx code and 1 ICD-9-CM 780.39 (other convulsions) code at separate encounters; (3) the ICD-9-CM code 345.3 (grand mal status), occurring twice and separated by at least 30 days, occurring with ICD-9-CM 780.39 and separated by at least 30 days or occurring with ICD-9-CM 345.xx on separate days. They assessed the sensitivity of their findings by analyzing the data after increasing the rigor of the epilepsy diagnostic criteria using 12 case definitions, with the most stringent definition of epilepsy requiring 4 or more separate ICD-9-CM codes of 345.xx as the primary code during encounters at least 30 days apart. Patients receiving a prescription for at least a 30-day supply of an AED during the follow-up period were classified as receiving treatment. The authors performed a primary study, which included 59 970 patients who met the inclusion criteria, 36.7% of whom remained untreated up to 3 years after diagnosis, as well as a validation study including 30 890 patients, 31.8% of whom remained untreated up to 3 years after diagnosis. Using the most stringent definition of epilepsy, which included 9004 patients, 4% remained untreated up to 3 years after diagnosis.