social functioning, blood samples for genetic analyses, and a neuropsychological and neurophysiological battery to assess brain function (see 2. Sample and Clinical Data). Data were collected at seven study sites across the United States, each lab operating under the same protocol, resulting in collection of similar data across all sites that could be pooled in analyses. 5 , 6 , 7 , 8 An overview of the overarching objectives of COGA, as well as detailed description of the COGA study data collection are provided elsewhere in this issue (see 1. Overview; 2. Sample and Clinical Data; 4. Genetics; 5. Functional Genomics).
