A Core Outcome Set (COS) is a standardised list of outcomes that should be reported as a minimum in all randomised controlled trials (RTCs). It is developed using consensus methods to ensure it includes what is important to patients, healthcare professionals and researchers.

The failure to use COS results in research waste and clinical trials that do not measure what is important to patients, and hence fail to adequately inform clinical practice. The aim of this fellowship is to develop a COS for adult epilepsy, including international stakeholders, that will be adopted internationally for use in future RCTs.

This proposal comprises multiple phases.

• Phase 1: systematic review methodology will be used to identify outcomes already measured in adult epilepsy RCTs.
• Phase 2: narrative synthesis methods will be used to describe outcomes important to people with epilepsy from published focus groups and qualitative interviews. The outcomes highlighted will be taken through to phase 3
• Phase 3: Delphi surveys and face-to-face meetings will be used to obtain international consensus on an epilepsy specific COS.
• Phase 4: similar consensus methods will be used to determine which outcome measurement instruments should be used to implement the COS in practice.

The proposal has scientific endorsement from the International League Against Epilepsy and the International Bureau for Epilepsy, and the consensus process will include key international stakeholders. An epilepsy specific COS should lead to improved trial design, facilitate systematic review and allow better informed clinical decision making