The present findings based on sharing of etiologic influences were not consistent with the hypothesis based on studies of mental disorders in adults that anxiety disorders and depression can be parsed into two correlated higher-order “distress” (MDD, dysthymia, GAD, and post-traumatic stress disorder) and “fears” (specific phobia, agoraphobia, social phobia, and panic disorder) domains.17, 35, 36 It is possible that separate higher-order fears and distress factors would have been identified in the present study had symptoms of post-traumatic stress disorder been assessed, but it also is possible that the distinction between the distress and fears domains only emerges in adulthood. Still, it is important to note that internalizing factor in Figures 1 and 2 might be considered to be a “fears” factors because MDD and GAD did not load on it in the best-fitting models.
