The diagnostic use of the MMPI in organic brain dysfunction.

Investigated two problem areas: (a) difficulty in the diagnoses of some types of organic brain dysfunctions; and (b) lack of accuracy in the differentiation of patients with organic disorders from patients with nonorganic disorders. Hospitalized male Ss (N = 152) were selected by diagnoses to form one nonorganic and three organic groups. For each group, data from Ss' MMPI protocols were analyzed via Cattel's Coefficient of Profile Similarity and discriminant analysis. Both MMPI factor scales (Barker, Fowler, & Peterson, 1971) and the usual clinical scales were used and compared in all analyses. Statistically significant differences among groups were found on both scales, with a greater separation of the groups provided by the factor scales. Results suggest that the MMPI, through the use of regression formulas derived from discriminant analysis of multiple groups, may be of diagnostic utility in organic brain dysfunction.