A Correlation Study between the Shipley-Hartford Test of Mental Maturity and the Minnesota Multiphasic Personality Inventory

The Minnesota Multiphasic Personality Inventory (MMPI) has been v recognized as a helpful tool to the psychologist in identifying abnormal characteristics (Leverenz, 1956; Modlin, 1956; Hathaway and Mckinley, 1967; Hock, 1970). Likewise the Shipley-Institute of Living Scale for Measuring Intellectual Impairment (S-H) has also been recognized as a helpful tool in identifying emotional impairment (Pollack, 1942; Halstead, 1943; Fleming, 1943; Wright, 1946; Garfield and Fey, 1948; Lewinsohn, 1963) . Despite the research which suggests both tests are capable of helpful diagnosis in the general area of psychological impairment (Welch, 1956; Lewinsohn, 1963), little if any work has been done examining the compatibility of the two instruments. Therefore, a correlation study was made between the two tests. Sixty-one male in-patients of the Wyoming State Hospital, between the ages of 18-45 (Garfield and Fey, 1948) and having a verbal IQ of 14. 3 years (Shipley and Burlingame, 1941), were administered both the S-H and the MMPI. The conceptual quotient (CQ), a measure of intellectual impairment based upon the assumption that where there is intellectual impairment, vocabulary is less affected than is the capacity for abstract thinking and that in such cases there will be a discrepancy between vocabulary level and the ability to handle abstract problems (Lewinsohn, 1963, p. 444) of the S-H, was correlated with the number of Peterson\u27s Psychotic Profile Signs (Peterson, 1954) a patient might acquire after taking the MMPI. Peterson\u27s model was chosen as the criteria for discriminating MMPI profiles because of its relative case of use and successful experimental value (Peterson, 1954). Secondly, the CQ score was correlated with each individual subtest T score of the MMPI. Analysis of the experimental data was achieved statistically by use of Pearson\u27s product-moment correlation. The results of the study showed no significant correlation between S-H\u27s CQ and Peterson\u27s signs. Further, no significant correlation was found with eight of the ten subtest scores on the MMPI and Shipley\u27s CQ. However, there was a low but significant correlation between Shipley\u27s CQ and the Hy and Mf subscales of the MMPI. No determining factor was found to explain the common variance in these two correlations