We included 208 healthy controls (HCs), with a total of 475 structural magnetic resonance imaging (sMRI) brain scans between the ages of 9 and 22 years. Any neurological or psychiatric illnesses were exclusionary (Giedd et al., 1999). Seventy-seven of the 208HCs included in this study had been part of an earlier, smaller study by our group that related Val dose to CT within HCs (Shaw et al., 2009). Our present study includes more HCs than our earlier study, with more sMRI scan for each year of the age-range under examination.
