SUMMARYObjectives: Precipitants of seizures are often reported by patients and carers, but the accuracy of these claims remains unknown. Focusing on epilepsy in people with intellectual disability (ID), the aims of this work were to (1) identify a set of methods for assessing the validity of reported seizure triggers in individual patients; and (2) undertake an initial assessment of the ease of implementation and acceptability of the method by applying it to a series of cases. Methods: Data collection materials (developed with carer involvement) consisted primarily of carer diaries of seizure and trigger occurrences. Statistical analysis of diary data was using the self-controlled case series method. Unlike previously used methods, the analysis method included a means of choosing the time window, following trigger exposure, during which changes in seizure likelihood are to be assessed. Results: The method developed was trialed in five adults with ID and epilepsy, who had a range of ID severities and living circumstances. Examples of the application of the method in two of the five cases are presented for illustrative purposes. The method was acceptable to participants and most aspects successfully implemented. Significance: This method may be useful for clinicians and researchers wishing to investigate possible triggers in individual patients with epilepsy and ID. It also supports the identification of a statistically defined time window following exposure to a precipitant, during which the risk of developing a seizure is increased. The identification of such a window has value not just in contributing to clinical management, but also in guiding future work into the mechanisms of seizure precipitation. KEY WORDS: Epilepsy, Seizure, Precipitant, Intellectual disability.Precipitants for individual seizures are often reported by patients and carers.1-4 However, doubts remain regarding the accuracy of these reports and a reliable method of identifying events or processes that for an individual patient are associated with an increased risk of seizure occurrence would have important implications. Clinically it would create the potential for reducing seizure occurrence by avoiding these events (where possible). Theoretically, investigation of mechanisms by which these events increase seizure risk could provide novel insights into why seizures occur when they do.Focusing on seizure precipitants in epilepsy, existing studies 5-8 have used various methods for data collection and analysis. We sought to develop, describe, and trial a complete set of methods to investigate seizure precipitants FULL-LENGTH ORIGINAL RESEARCH in epilepsy. We sought to address an important shortcoming of existing methods; namely, the use of poorly justified assumptions regarding the time course (or "risk window") over which proposed triggers may act. Furthermore, we sought a clinically focused method that enabled direct investigation of whether one or more carer-or patient-reported triggers are indeed associated with increased seizure likelihood...