Review| Volume 142, 109154, May 2023

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Seizure severity assessment tools for adult epilepsy patients: A systematic review


      • There are eight assessment tools available for measuring seizure severity in adult patients with epilepsy.
      • The identified tools were presented either as a single scale or divided into several sections (subscales).
      • Details on the seizure events e.g., warning, automatisms, motor involvement, consciousness, postictal injuries, and duration of seizure are important elements in assessing seizure severity.
      • Future works should revolve around integrating survey-based assessment with objective measures in a single module.



      Seizure outcomes from antiseizure medication (ASM) therapy can be measured across various domains using assessment tools. The available tools may contain an array of different components or items. Seizure severity assessment, as opposed to seizure frequency count may have been a more accurate measurement in determining the effectiveness of ASM therapy. This study aimed to review studies developing seizure severity assessment tools for adults with epilepsy, describe the development methods and validation, and compare the list of items in these tools.


      The systematic search utilized established databases such as Scopus, Ovid, Web of Science, Medline, Wiley Online, and Cochrane Library. Studies published from inception to December 15, 2022, were selected. Publications describing the development of tools to measure seizure severity among adult epilepsy patients were included. Outcome measures including the tool’s content, development methods, validity, and reliability assessments were compared.


      The search produced eight publications describing the development of eight seizure severity assessment tools. One of these tools is part of a multidimensional assessment of the overall impact of epilepsy. The frequently used method in the initial development was the qualitative method (n = 6) where two publications reanalyzed the items from previous studies. Face validity was the most common validation test conducted (n = 4). At least one reliability assessment was conducted for each of the tools, most commonly by the test–retest method (n = 6) and inter-rater reliability (n = 5). All of these tools cover the components of pre-ictal (warning/aura), ictal, and postictal (recovery) events.


      The identified tools described the assessment of seizure severity using various subscales. The emergence of new methods in quantifying seizure severity unfolds opportunities in discovering more comprehensive assessments of seizure severity in both clinical trials and daily clinical practice.


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