Latent Structure of the Mississippi Scale for Combat-Related Post-Traumatic Stress Disorder: Exploratory and Higher-Order Confirmatory Factor Analyses

A series of factor analyses evaluated the dimensionality of the Mississippi Scale for Combat-Related Post-Traumatic Stress Disorder. Over 2,200 Vietnam theater and era veterans were divided into three random subsamples, each of which was used in a separate stage of analysis. Initial exploratory factor analyses suggested an underlying single-factor solution. In the second subsample, a second-order solution comprised of a general factor subsuming several first-order factors was supported using chi-square difference testing. This model was successfully replicated with the third subsample. Cumulative evidence suggests that the latent structure of the Mississippi Scale is best represented as an umbrella Post-Traumatic Stress Disorder (PTSD) factor leading to four subsidiary facets or dimensions.