Here we performed the largest coordinated worldwide study of cortical measures in patients with OCD compared to healthy controls. We extracted cortical thickness and surface area estimates of 1905 OCD patients and 1760 healthy controls, using harmonized data processing and analysis strategies across 27 sites. We also aimed to establish the potential modulating effects of demographic and clinical characteristics. Based on the prior literature, we expected lower cortical thickness in ACC, OFC, dorsomedial prefrontal cortex (dmPFC) and parietal regions, in OCD patients compared to healthy controls. In addition, we explored the cortical surface area profile in OCD.
