function using electro‐encephalograms (EEGs) were included 13 , 14 (see, 3. Brain Function in this issue for further information on COGA brain function studies). These rich data, combined with the family‐based design, have lent themselves to advances in the field of genetics: from parametric to non‐parametric linkage, to candidate genes and finally, genome‐wide association studies—all conducted against a backdrop of rich and repeated multimodal data collection.
