Which Outcomes Should We Measure in Adult Epilepsy Trials? The Views of People with Epilepsy and Informal Carers

Objective: So that informed treatment decisions can be made, clinical trials need to evaluate treatments against domains that are important to people with epilepsy (PWE), their carers, and clinicians. Health professionals have identified domains of importance to them via the International League Against Epilepsy's Commission on Outcome Measurement (COME). However, patients and carers have not been systematically asked.

Methods: Via the membership of the British Epilepsy Association, we recruited and surveyed 352 PWE and 263 of their informal carers. They were presented with 10 outcome domains (including the 5 identified by COME) and asked to rate their importance using a 9-point Likert scale. They were also asked to identify any additional domains of importance.

Results: The patients' mean age was 49years, the median number of years since diagnosis was 20, and 65% had experienced seizures in the prior 12months. Most carers were the spouse or parent. Patients' and carers' mean ratings indicated that their outcome priorities were similar, as were those of patients who had and had not experienced recent seizures. There was consensus among patients that 6 domains were of critical importance. These included the 5 identified by COME (namely, and in order of importance, the effects of the treatment on "Seizure severity", "Seizure frequency", "Quality of life", "Cognitive function", and "Adverse events"), as well as one additional domain ("Independence/need for support"). There was consensus among carers that the 5 COME domains were also critically important. They, however, identified 3 further domains as critically important. These were the effects of the treatment on patient "Depression", "Anxiety", and "Independence/need for support".

Conclusions: Our study found some overlap between the priorities of PWE, carers, and health professionals. They, however, highlight additional areas of importance to patients and carers. Our results could inform a core outcome set for epilepsy that represents the domains that should be reported as a minimum by all trials. This could promote trials which produce meaningful results and consistency in measurement and reporting.