The utility of the AIMPI has been questioned because of possible regional specificity, and development of regional norms has been suggested occasionally. ( 8 ) The MMPI scales were developed in the Midwest and have been accepted as a measurement of personality dimensions relevant to that area; they are less accepted as a reflection of personality patterns purported to be more typical of other regions of the U. S.
Black ( 2 ) and Goodstein ( 5 ) investigated profile characteristics of college students in various regions of the U. S. No reliable differences were found, although the profiles were determined to be characteristic of college students as a group. Similarly, Smith(8) examined the RlMPI profiles of prisoners in various state institutions.
Once again, no regional differences were found. The samples of these studies, however, appeared to have been homogeneous and not representative of psychiatric patients in general.
Sex differences have been investigated with a psychiatric population that is only slightly more representative. Aaronson(') examined the codes presented in Hathaway and Meehlc6) with regard to sex differences in high-point scales. Scales 1 and 7 were more frequently the high-point for male patients, while scales 3 and 6 were more frequently the high-point for female patients. Because these results were found with a primarily midwestern group of patients, the possibility existed that Aaronson's sex difference findings were related to that population. Consequently, it was felt desirable to investigate the possibility of regional and sex differences among a more broadly selected and heterogeneous group of psychiatric patients.
Recently, a population felt to be representative of patients of psychiatrists and clinical psychologists nationally has come into existence. The Roche Psychiatric Service Institute (RPSI) makes available computerized interpretations of the *Presented at the Midwest,ern Psychological hsociation, Cincinnati, April 30, 1970. Appreciatioil is expressed to Miss Dolores Loyko of Hoffmanii-La Roche, Inc. for her help in the dat,a analyses.