In the present study, we compare factor analytic models of post-traumatic stress disorder
(PTSD) in terms of their fit and predictive utility with regard to external correlates such as
comorbid diagnoses and other psychosocial outcomes. Competing models were compared and
validated in an epidemiological dataset (N = 23,936). Confirmatory factor analyses (CFA) using
models from prior literature with four through seven factor solutions were conducted. The seven
factor Hybrid model, the six-factor Anhedonia model, and the six-factor Externalizing Behaviors
model were the first, second, and third best-fitting models, respectively; however, the
inconsistency of associations with external correlates and high factor intercorrelations suggested
that higher-factor solutions may sacrifice parsimony for minimal gains in utility. The Anhedonia
and Hybrid models’ separate Anhedonia and Negative Affect factors (a core difference from
other models) demonstrated limited utility in differentially associating with distinct constructs
under the internalizing umbrella. Anhedonia and Negative Affect also correlated highly with each
other and nearly perfectly with the factors composed of their combined symptoms (e.g. the
Externalizing Behaviors model’s Numbing factor), suggesting a "lumped" factor would be more
parsimonious. The Externalizing Behaviors model showed predictive utility in accounting for
externalizing comorbidities as well as differentiating among constructs within the internalizing
spectrum; however, it lacked robust associations with externalizing behavioral outcomes such as
frequency and quantity of drinking. These results give reason for concern that predominant
structural models of PTSD may not be adequate for discriminating among or predicting
functional outcomes related to PTSD symptomatology in trauma-exposed populations.