In schizophrenia, for example, decades of studies have reported morphometric differences in patients versus controls, for a range of different structures. ENIGMA offers a promising framework to rank brain measures in order of their effect sizes for case–control differences; these effects could also be further weighted based on their genetic correlation with the illness, to give another ranking. Nor is it expected that the disease should have identical effects on the brain in all cohorts; the variety of participating cohorts in ENIGMA makes it possible to dig deeper into medication-related, or even geographic or demographic factors to explain why brain differences vary so drastically across different studies (see Fig. 5 for the locations of ENIGMA sites in disease-related working groups).
