Descriptive statistics are provided in Table 2 in Iacono et al. (2014) in this issue. Mean amplitudes were 5% to 11% larger for females than males and 61% to 72% larger for adolescents than adults. Plots of the distribution of each endophenotype indicated that the assumption in regression analysis of normally distributed scores was reasonable (see Figures S1 and S2 in supporting information).
