Miach, P. et al. (2000). Utility of the MMPI-2 in assessing gender dysphoric patients.
Journal of Personality Assessment, 75, 268-280.
Since the 1970s and early 1980s the Minnesota Multiphasic Personality Inventory (MMPI) has been used to investigate the contention that transsexualism is evidence of psychopathology, either as a severe personality disorder or psychotic disorder. Miach et. al. conducted a study to compare the MMPI-2 profiles of 86 males candidates requesting sex reassignment surgery. During the minimum 2-year waiting period for surgery the male candidates were continuously assessed over a 6-month or longer period and were diagnosed either as transsexual or with gender identity disorder of adolescence and adulthood, nontranssexual type (GIDAANT), the two defined conditions within the spectrum of gender identity disorder according to DSM-III-R. Miach et al. chose the MMPI-2 over other personality measures because it addresses a broad range of psychological symptoms and personality problems and is the most widely researched personality scale. Transsexualism is described by three criteria: (a) pervasive discomfort about one’s assigned sex, (b) persistent preoccupation for at least 2 years with getting rid of one’s sex characteristics and acquiring the sex characteristics of the other sex, and (c) puberty having been reached. A diagnosis of GIDAANT requires the first and third criteria be met, with an absence of the second criterion and with persistent cross-dressing for purposes other than sexual excitement (Miach et al., 2000).
The participants for the study were obtained from Monash Medical Centre Gender Dysphoria Clinic. The minimum age of 18 years was required for admission into the program and eligibility for assessment. The study was conducted from May 1993 through October 1996. In individual assessment sessions, the MMPI-2 was administered to a total of 86 consecutive male to female candidates referred for a psychological assessment to determine their suitability for sex reassignment surgery. Three of the candidates dropped the program prior to completing the psychological assessment and were therefore excluded from the study. The remaining of the 86 candidates completed the psychological assessment.
Psychological testing was not used to diagnose transsexualism but to establish the presence of additional psychopathology that could create difficulties during the 2-year trial period or determine suitability for sex reassignment surgery. Two psychiatrists and one clinical psychologist independently assessed each candidate after several clinical interviews. A team conference was then held to integrate the three clinicians’ material and clinical DSM-III-R evaluation. Disagreements about diagnosis were resolved through discussion or the specification of additional necessary information. All study patients diagnosed as transsexuals through this process met the DSM-III-R criteria for transsexualism. Those diagnosed as having a nontranssexual gender dysphoria (GIDAANT) were characterized by either transient stress-related gender dyphoria or confusion about issues of identity (Miach et al., 2000).
The study yielded the following results, forty-eight of the 82 candidates were diagnosed as transsexual, and 34 were diagnosed as GIDAANT. Fourteen (29%) of the transsexual candidates were assessed as having an additional psychiatric disorder and 22 (65%) of the GIDAANT group were assessed as having an Axis I and Axis II disorder.
The transsexual group did not demonstrate any significant elevation on the validity or the clinical scales other than a moderate elevation on Scale Mf (T=65). Indications of psychopathology for the GIDAANT group were several moderate elevations on two clinical scales (D and Sc), on one of the content scales (DEP), and on two of the supplementary scales (PK and PS), indicating emotional distress. When comparing the proportion of individuals in each group who had elevated T scores on the clinical scales, the GIDAANT group showed a consistently higher proportion of individuals scoring in the clinical range (Miach el al., 2000). To compare the means for all the scales for the transsexual and GIDAANT groups, two-tailed t test were performed. A .005 or greater level of significance was used to reduce the risk of Type 1 error. Nearly all the significant differences between the GIDAANT and transsexual group on the validity, clinical, content, and supplementary scales were indicative of greater psychopathology in the GIDAANT group than in the transsexual group. Significant differences between Mf2 (Hypersensitivity/Anxiety) and Mf4 (Low Cynicism) were consistent with other indications of greater psychopathology in the GIDAANT group than in the transsexual group. A cluster analysis was performed in order to divide the sample into a higher pathology group and a lower pathology group. Results yielded a statistically significant difference in cluster membership for the diagnostic groups. Eighty five percent (almost all) of transsexuals were in the lower pathology cluster whereas 47 percent (nearly half) of the GIDAANT group was in the higher pathology cluster. These results emphasize the usefulness of the MMPI-2 in assessment of the severity of pathology in candidates presenting for sex reassignment surgery and the importance of more rigorous diagnosis to differentiate groups in which the common features is a request for sex reassignment surgery (Miach et al., 2000).
Utility of the MMPI-2 in assessing gender dysphoric patients
a. The MMPI-2 was widely used in studies to investigate transsexualism as evidence of psychopathology.
b. The MMPI-2 addresses a broad range of psychological symptoms and personality problems and is the most widely researched personality scale.
II. Participants and procedures in the study
a. Participants were obtained from the Monash Medical Centre Gender Dysphoria Clinic, age range of 21 and 55, but clients are accepted from the age of 18 for assessment and admission to the program.
b. A total of 86 consecutive male to female candidates were administered the MMPI-2 in individual assessment sessions.
c. The psychological testing occurred after completion of the waiting period of 6 to 9 months after the admission of the program.
d. Each candidate was independently assessed by two psychiatrists and one clinical psychologist after several clinical interviews
e. All study patients diagnosed as transsexuals through this process met the DSM-III-R criteria for transsexualism. Those diagnosed as having a nontranssexual gender dysphoria (GIDAANT) were characterized by either transient stress-related gender dysphoria or confusion about issues of identity.
III. Results yielded by the MMPI-2 in assessing gender dysphoric patients
a. Forty-eight of the 82 candidates were diagnosed as transsexual, and 34 were diagnosed as GIDAANT.
b. Twenty-nine percent of transsexuals were diagnosed as having an additional psychiatric disorder. Sixty-five percent of the GIDAANT group was assessed as having an Axis I or Axis II disorder.
c. Two-tailed t test were performed to compare the means for all the scales for the transsexual and GIDAANT groups. A .005 or greater level of significance was used to reduce the risk of Type I error.
d. Almost all of the transsexual (85%) were in lower pathology cluster whereas nearly half (47%) of the GIDAANT group was in the higher pathology cluster.
e. The results of the study show lack of significant psychopathology in the MMPI-2 profiles of transsexuals. Also, the results emphasize the usefulness of the MMPI-2 in assessment of the severity of pathology in candidates presenting for sex reassignment surgery and the importance of more rigorous diagnosis to differentiate groups in which the common feature is a request for sex reassignment surgery.