Abstract
The short- and long-term outcome of epilepsy surgery has been mostly assessed by observational studies because experimental designs in surgical patients are often unfeasible and have ethical implications. However, observational studies have methodological limitations, which include the retrospective design, the use of referral populations, the small sample size, the enrolment of patients at differing inception points, the use of differing inclusion criteria, differing definitions of prognostic predictors and outcome measures, the unmasked assessment of outcome, the short follow-up, the changing technologies and surgical procedures, and the inadequate statistical methods. These limitations are incorporated in systematic reviews of epilepsy surgery studies and cannot replace well-conducted prognostic studies. Key features of these studies should include representative populations at risk, well-defined inception cohorts, satisfactory and complete follow-up, prospective design, and standard definition of prognostic factors.
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Beghi, E. (2015). Methodological Demands on Observational Studies of Outcomes After Epilepsy Surgery. In: Malmgren, K., Baxendale, S., Cross, J. (eds) Long-Term Outcomes of Epilepsy Surgery in Adults and Children. Springer, Cham. https://doi.org/10.1007/978-3-319-17783-0_2
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DOI: https://doi.org/10.1007/978-3-319-17783-0_2
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