The consistency of the 2011 studies on the metastructure underlying the comorbidity of substance use and psychiatric disorders argues for investigation of etiological factors underlying the dimensions rather than the individual disorders. At the same time, adding new disorders to the analyses does not always produce the cleanly divided internalizing/externalizing structure found previously. Finally, the fact remains that some individuals manifest symptoms of one disorder but not another within a dimension. A better understanding of the reasons for these different clinical presentations within a dimension should advance our understanding of the etiology and treatment.
