The study by ENIGMA Clinical High Risk for Psychosis Working Group pooled MRI data from 31 international sites, including 1,792 individuals at CHR and 1,377 healthy controls, giving a total sample of 3,169 participants. Among the CHR group, longitudinal clinical follow‑up identified 253 individuals who later developed psychosis (CHR‑PS+) and 1,234 who did not (CHR‑PS−).5
Structural MRI measures were extracted using harmonized FreeSurfer analysis software, including regional cortical thickness, surface area, subcortical volumes, and global measures (mean cortical thickness, total surface area, and intracranial volume). Group differences were assessed within a mega‑analysis framework, with effect sizes reported as Cohen’s d with 95% confidence intervals and correction for multiple comparisons.5
Abbreviations: CHR=clinical high risk; MRI=magnetic resonance imaging
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