Using the MCMI‐I to Diagnose Personality Disorders in Inpatients: Axis I/Axis II Associations and Sex Differences

The present investigation examined the Millon Clinical Multiaxial Inventory (MCMI‐I) personality disorder (PD) diagnostic categories and personality disorder dimensional (BR) scores in 87 patients, to evaluate Diagnostic and Statistical Manual (Third Edition/Revised) (DSM‐III/R) statements as regards Axis 1/Axis II associations and PD sex differences. Patients formed three clearly diagnosed Axis I groups: a schizophrenic group (n = 35); an affective group (n = 30); and a mixed group who were given a range of nonaffective, nonschizophrenic diagnoses (n = 22). Using the MCMI‐I, PD scores were compared across the three groups. The strongest results in line with DSM‐III/R statements were that the affective group was much more likely than the remaining two groups to obtain borderline PD diagnoses, and females were significantly more likely to obtain a borderline diagnosis. Contrary to DSM‐III/R statements, the schizophrenic group did not obtain greater proportions of schizoid, schizotypal, or paranoid PDs, compared to the other two Axis I groups. Issues pertaining to the validity of the MCMI‐I are raised, and the possible impact on results are discussed. 1991 Australian Psychological Society