Incremental validity of the Minnesota Multiphasic Personality Inventory (MMPI-A) and Rorschach Inkblot Test in predicting the number and severity of adolescents' maltreatment histories

There are limited empirical data to support the statistical and clinical utility of the Minnesota Multiphasic Personality Instrument-Adolescents (MMPI-A) and the Rorschach Inkblot Test within a maltreated sample. Therefore, this study examined if the MMPI-A and the Rorschach predicted the number and severity of maltreatment subtypes for abused and neglected adolescents. MMPI-A scales and Rorschach were organized according to four personality constructs: 1) self-perceptions and sense of personal competence (the Self-System); 2) emotional awareness and control (Affective Regulation); 3) reality testing and efficiency of information processing (Cognitive Processes); and 4) social interest and skillfulness (Interpersonal Relatedness). The sample was drawn from an existing database, adolescents who were referred by Child Protective Services. All of the adolescents experienced some form of abuse or neglect that typically resulted in their removal from the home. The Maltreatment Classification System (MCS; Barnett, Manly, & Cicchetti, 1993) was applied to systematically code maltreatment attributes. Multiple regression analysis indicated that the MMPI-A scales and Rorschach variables measuring the Self-System scales both predicted the severity of Physical Abuse. When entered as separate blocks in a hierarchical regression analysis to determine if the two instruments added information above and beyond the other, regardless of the order, the MMPI-A scales and Rorschach variables added variance in predicting Physical Abuse severity. The Self-System Rorschach variables also predicted the number of maltreatment subtypes. The Cognitive Processes MMPI-A scales predicted the severity of Sexual Abuse. The Cognitive Processes Rorschach variables predicted the number of maltreatment subtypes. The Interpersonal Relatedness MMPI-A scales predicted the severity of Emotional Maltreatment. The Interpersonal Relatedness Rorschach variables predicted the severity of Sexual Abuse. There were no significant relations among MMPI-A scales and Rorschach variables despite being purported to measure similar constructs. Issues of instrument reliability and validity, variation in response format, and the complexity of adolescents’ trauma histories are offered as possible reasons for the large number of MMPI-Scales and Rorschach variables that did not share relations with each other as well as maltreatment attributes. This study underscores the importance of considering clients’ histories as well as instrument integrity when interpreting data in a psychological evaluation.