We first estimated the genetic correlations among our 10 proposed indicators. The correlations between SUDs and externalizing phenotypes varied substantially between SUDs (Figure 2). Of the four SUDs, cannabis use disorder was most strongly correlated with the externalizing phenotypes (rgs ranged from 0.45 [risk tolerance] to 0.72 [smoking initiation]) whereas problematic tobacco use was least strongly correlated with externalizing phenotypes (rgs ranged from −0.06 [cannabis initiation] to 0.45 [ADHD]).
