Psychometric properties of the MMPI-2-RF Somatic Complaints (RC1) scale.
The MMPI-2 Restructured Form (MMPI-2-RF; Tellegen & Ben-Porath, 2008) was designed to be psychometrically superior to its MMPI-2 counterpart. However, the test has yet to be extensively evaluated in diverse clinical settings. The purpose of this study was to examine the psychometric properties of the MMPI-2-RF Somatic Complaints (RC1) scale in a clinically relevant population. Participants were 399 patients diagnosed with either epilepsy or psychogenic nonepileptic seizures on the basis of video-electroencephalograph monitoring. The internal structure of the MMPI-2-RF was evaluated using taxometric, confirmatory factor analysis, and item response theory procedures. Data from 4 content-specific scales directly related to RC1 (Malaise, Gastrointestinal Complaints, Head Pain Complaints, and Neurological Complaints) indicated that the latent construct of somatization is a dimensional variable with a bifactor structure. However, consistent with the scale's construction, a unidimensional model also provided adequate fit. A 2-parameter logistic item response theory model better accounted for observed item responses than did 1- or 3-parameter models. Results suggest that the RC1 scale is most precise for T score estimates between 55 and 90. Overall, the scale appears to be well suited for the assessment of somatization.
Thomas
Michael L
ML
Department of Psychology, Arizona State University, 950 South McAllister, P.O. Box 871104, Tempe, AZ 85287, USA. michael.t@asu.edu
Locke
Dona E C
DE
D000328:Adult; D004569:Electroencephalography; D004827:Epilepsy / Q000503:physiopathology / Q000523:psychology; D005163:Factor Analysis, Statistical; D005260:Female; D005767:Gastrointestinal Diseases / Q000523:psychology; D006261:Headache / Q000523:psychology; D006801:Humans; D008950:MMPI / Q000706:statistics & numerical data; D008297:Male; D008960:Models, Psychological; D011594:Psychometrics; D011602:Psychophysiologic Disorders / Q000523:psychology*; D015203:Reproducibility of Results; D013001:Somatoform Disorders / Q000523:psychology