Be sure to read the fine print: The agency for healthcare research and quality comparative effectiveness report on antiepileptic drugs

For many questions related to the pharmacotherapy of epilepsy, there are few or no published data. This lack of data presents dilemmas to practitioners who must make informed, rational decisions about therapy on a daily basis and to policymakers dealing with drug formulary management and reimbursement. Reliance on randomized, clinical trial data is inefficient because of the extensive time and expense involved in conducting a study and the inability to answer every question encountered in practice. In addition, results from randomized, clinical studies are not fully applicable in the clinical setting because of short trial duration and the frequent use of surrogate controls that are rarely seen in routine practice.