A Two-Feature Quantitative EEG Index of Pediatric Epilepsy Severity: External Pre-Validation on CHB-MIT and Roadmap to Dravet Cohorts

Objective biomarkers for staging pediatric epileptic encephalopathies are scarce. We revisited a large open repository -- the CHB-MIT Scalp EEG Database, 22 subjects aged 1.5-19 y recorded at 256 Hz under the 10-20 montage -- to derive and validate a compact quantitative index, DS-Qi = (theta/alpha)_posterior + (1 - wPLI_beta). The first term captures excess posterior slow-wave power, a recognized marker of impaired cortical maturation; the second employs the debiased weighted Phase-Lag Index to...