Derry P A, McLachlan R S
Department of Psychology, University Hospital, University of Western Ontario, London, Canada.
Seizure. 1996 Mar;5(1):35-40. doi: 10.1016/s1059-1311(96)80060-4.
Although the original Minnesota multiphasic personality inventory (MMPI) showed promise in the psychometric discrimination of patients with epileptic seizures and pseudoseizures, inconsistencies and relatively low rates of accuracy have been reported. The present study evaluated the restandardized MMPI-2 for its accuracy in discriminating patients with pseudoseizures in a population with intractable epilepsy. MMPI-2 profiles for 139 consecutive adult inpatients (24 with pseudoseizures) were classified as a pseudoseizure pattern if they had (a) a T score on Scale 1 and/or 3 > or = 65, (b) Scale 1 or 3 in the 2-point high code, and (c) if 1 or 3 was not the highest scale, it was < or = 6T from the highest scale. Compared to studies using the original MMPI, it was expected the MMPI-2 would more accurately classify patients in each group. Preliminary analyses revealed pseudoseizure patients had a greater history of mental health interventions and were older when their seizure disorder began, relative to the epilepsy patients. A classification accuracy of 92% was found for pseudoseizures and 94% for epilepsy patients. For the pseudoseizure group, clinically meaningful MMPI-2 elevations followed a 3-1-2 pattern. No mean elevations above a T value of 65 were seen in the epilepsy group.
