Clinical validity of the MMPI-168.

Summary.-This study investigated whether clinical judgments based on the MMPI-168 are comparable to those based on the smndard MMPI. Each of 15 pairs of clinical psycholog~sts were given a combination of short and standard form profiles from thrce psychiatric patients and asked both to complete an 18-item symptom rating scale for each patient and to decide upon each patient's diagnosis. Analyses of symptom ratings, with one exception, yielded non-significant P ratios and, diagnostic choices did not vary significantly as a function of MMPI form (short vs long) interpreted. Implications of these findings are discussed in terms of the clinical use of the MMPI-168. Of the many available short forms of the Minnesota Multiphasic Personality lnventory (MMPI), the MMPI-168 is perhaps the most promising. In fact, studies employing computer-effected discriminant functions (2, 3) have shown that the MMPI-168 is equivalent to the standard MMPI in discriminating among diagnostic groups. While these studies are encouraging, little research has been published to determine whether this short form, when in the hands of experienced clinicians, leads to clinical predictions similar to those derived from the standard MMPI. Further, most studies of the validity of the MMPI-168 have employed psychiatric diagnosis as the sole validity criterion. The current study employed a sample of clinicians to determine if the MMPI168 and standard MMPI yield comparable clinical predictions abut a variety of specific symptoms as well as patients' diagnoses. The dependent measures were incorporated into this 19-item questionnaire. The first 18 items were the standard symprom rating items of the Brief Psychiatric Rating Scale (3), but the usual 7-point scale for rating symptom severity was replaced by a 4-point (0 to 3) scale. The nineteenth item was a multip1e:choice item for indicating the patient's diagnosis. Included as diagnostic choices in this item were Schizophrenic Disorder. Paranoid Disorder, Affective Disorder. Anxiety Disorder, Somatoform Disorder, Dissociative Disorder, Personality Disorder, and Adjustment Disorder. Thirty Ph.D. clinical psychologists (26 male, 4 female) who had interpretive experience with the MMPI were obuined as subjects for this study. These clinicians were initially randomly divided into 15 pairs. Clinicians within each pair were subsequently given MMPI profiles from the same three patients and asked independently to complete a Symptom Rating and Diagnostic Questionnaire for each patient. For one patient both clinicians were given MMPI profiles based on the full MMPI; for the second parient, one clinician received a profile based on the full MMPI while the second received an MMPI-168 profile; and for the third patient, both clinicians received MMPI-168 profiles. This design was replicated across all 15 pairs of clinicians 'Requests for reprints should be directed to Jack D. Edinger, Ph.D., Psychology Service, Veterans Administration Medical Center, Durham, NC 27705. A longer version is on file in Document NAPS-04121 with Microfiche Publicati~ns, POB 351 3, Grand Central Station, New York, NY 10017. Remit $4.00 for fiche or $11.05 for photocopy. The authors express their appreciation to Ms. Gill Lunsford and Mr. 61in Hogan for their assistance in the typing of this manuscript. 3Greenville, NC.