(Kendler et al., 1997). However, up to now, 9/11 research has focused on individual disorders rather than the broader internalizing and externalizing dimensions, leaving unknown whether 9/11 effects are primarily through these domains, whether such effects differ between the internalizing or externalizing domains, and whether additional effects would be found for specific individual disorders. Further, differential effects on the internalizing and externalizing dimensions among those directly or indirectly exposed to 9/11 remain unknown. Addressing such questions is important not only to understanding 9/11 effects, but to building broader knowledge about the effects of large-scale traumatic events that affect major segments of the general population.
