Exploratory and Confirmatory Factor Analysis of Scale 8 (Sc) of the MMPI-2
Scale 8 (Sc) of the MMPI-2 is notoriously hard to interpret because of its heterogeneous item content. There have been a few serious attempts to better understand the psychometric properties of that scale, including Harris-Lingoes subscales and Comrey and Marggraff's (1958) factor analysis of the MMPI-2 clinical scales in the 1950s. These well-intended previous approaches were ridden with significant shortcomings such as the lack of sophisticated statistical methodology to deal with dichotomous variables. The foremost aim of this study is to adopt more rigorous exploratory and confirmatory factor analytic (EFA/CFA) approaches to derive and validate the latent variables of Scale 8 of the MMPI-2. A sample of 52,543 psychiatric inpatients and outpatients who had taken the MMPI-2 was equally divided into derivation and cross-validation samples for the study. In the first step of analysis, exploratory factor analysis of Scale 8 item data in the derivation sample led to the retention of five factors—Demoralization, Family Animosity, Somatic Symptoms, Persecutory Ideas, and Deviant Experiences—which were subjected to Geomin oblique rotation via Mplus and accounted for 57.21% of the variance of Scale 8. In the second step, confirmatory factor analysis in cross-validation demonstrated a good fit for the five-factor model. Results indicated that the only commonality between the latent factors of Scale 8 and the Harris-Lingoes Sc subscales was between Deviant Experiences and Sc6 (Bizarre Sensory Experiences). Other areas of overlap between the final model and other scales include the Demoralization factor with the RCd scale, the Persecutory Ideas factor with Scale 6 (Pa) and RC6, and the Somatic Symptoms factor with RC1 and the Health Symptoms (HEA) Content scale.
Doctor of Psychology in Clinical Psychology (PsyD)
Minnesota Multiphasic Personality Inventory, Confirmatory factor analysis, Psychological tests, Clinical psychology