Table 1. Inclusion/exclusion criteria.

Inclusion criteria:	Patients aged ≥15 years with no direct surgical approach who are discussed for invasive long-term video electroencephalography (EEG) monitoring with stereoelectroencephalography (SEEG) for presurgical evaluation of drug-resistant focal epilepsy at the multidisciplinary team discussion (MTD)
	Availability of complete non-invasive presurgical workup (including high-resolution MRI according to the in centre epilepsy protocol, video-telemetry with the recording of a minimum of one habitual clinical and EEG seizure, available as original files for review)
Exclusion criteria:	No telemetry/scalp EEG in centre
	No protocol MRI in centre
	Subdural/GRID electrodes
	For objectives #1 and #2: primary hypothesis is already multifocal and the SEEG study is solely performed with the intention to perform treatment/intervention that is, to determine the optimal localisation of thermocoagulation or evaluate for responsive neurostimulation.
	For objective #3: patients with multifocal primary hypothesis may be included as “control group’ consisting of patients who are no direct surgical candidates and are discussed for SEEG, but no SEEG is attempted for identifying a focal SOZ following the MTD.

SOZseizure-onset zone