Original Adult MMPI Norms in Normal Samples: A Review With Implications for Future Developments

Among the most consistent criticisms of the Minnesota Multiphasic Personality inventory (MMPI) has been the adequacy of the standardly employed adult norms. Recent work at the Mayo Foundation has provided revised adult norms, and the Restandardization Project at the University of Minnesota Press will soon provide an additional norm set. This article reviews findings from 21 studies of normal adults, comparing obtained MMPI scale values to the standard norms. These comparisons indicate that the traditional adult norms may have contained detectable degrees of bias since their publication, and that consistent patterns of differences from standard MMPI norms can be found in independent studies published as early as 1949. Two separate considerations impact on the development of new adult norms: the research need for adult norms which accurately reflect the response patterns of the general population and the clinical need to evaluate individual psychiatric patients on norms that produce codetypes related to an empirical literature spanning more than 40 years. This study notes the inherent tension between these two purposes and discusses the implications of new adult MMPI norms for research and clinical practice.     

MMPI adolescent norms: patterns and trends across 4 decades

This article examines central issues involving the accuracy of Minnesota Multiphasic Personality Inventory (MMPI) adolescent norms through examination of findings from eight investigations (n = 17,286), reporting MMPI mean values for samples of normal adolescents conducted between 1949 and 1964, and four studies (n = 1,758), based on adolescent samples collected since 1975. Issues related to sex and racial differences in adolescent samples are also examined. In addition, MMPI data from 1,315 normal adolescents, collected at the Mayo Foundation, and from 217 normal adolescents, collected in Norfolk, Virginia, are evaluated in relation to adult normative values on the Harris-Lingoes (Harris & Lingoes, 1955) content subscales to identify unique characteristics of adolescents' response patterns. Results support the adequacy of the adolescent norms, developed by Marks, Seeman, and Haller (1974), for evaluation of samples of normal adolescents collected between 1947 and 1965. MMPI patterns, produced by contemporary samples of adolescents collected since 1975, are elevated above the Marks et al. norms on most clinical scales. This latter finding indicated the need for the development of new adolescent norms that more precisely reflect current adolescent response frequencies and patterns. Finally, results from Harris-Lingoes subscales are reviewed to highlight unique aspects of adolescent developmental experience and to underscore the necessity of development of age appropriate adolescent norms for MMPI special scales.     

MMPI Adolescent Norms: Patterns and Trends Across 4 Decades

This article examines central issues involving the accuracy of Minnesota Multiphasic Personality Inventory (MMPI) adolescent norms through examination of findings from eight investigations (n = 17,286), reporting MMPI mean values for samples of normal adolescents conducted between 1949 and 1964, and four studies (n = 1,758), based on adolescent samples collected since 1975. issues related to sex and racial differences in adolescent samples are also examined. In addition, MMPI data from 1,315 normal adolescents, collected at the Mayo Foundation, and from 217 normal adolescents, collected in Norfolk, Virginia, are evaluated in relation to adult normative values on the Harris-Lingoes (Harris & Lingoes, 1955) content subscales to identify unique characteristics of adolescents' response patterns. Results support the adequacy of the adolescent norms, developed by Marks, Seeman, and Hailer (1974), for evaluation of samples of normal adolescents collected between 1947 and 1965. MMPI patterns, produced by contemporary samples of adolescents collected since 1975, are elevated above the Marks et al. norms on most clinical scales. This latter finding indicated the need for the development of new adolescent norms that more precisely reflect current adolescent response frequencies and patterns. Finally, results from Harris-Lingoes subscales are reviewed to highlight unique aspects of adolescent developmental experience and to underscore the necessity of development of age appropriate adolescent norms for MMPI special scales.     

Measuring depressive symptomatology of patients referred to a behavioral medicine clinic: Concordance of self-report measures

We measured depressive symptomatology of 134 outpatient veterans treated within a Behavioral Medicine Clinic utilizing three reliable instruments with depression subscales: Minnesota Multiphasic Personality Inventory (MMPI), Derogatis Stress Profile (DSP), and Symptom Checklist 90—Revised (SCL-90-R). Results indicate that although the instruments correlate significantly, they differ in sensitivity to depression and are clinically discordant. The MMPI classified a substantially higher number of patients as depressed than either the DSP or SCL-90-R. The present study argues that the discrepancy in clinical concordance and sensitivity of the three depression scales has considerable implications for psychologists concerned with the assessment and treatment of depression.     

Diagnosis of posttraumatic stress disorder with the MMPI: PK scale scores in somatization disorder

Clinic patients with diagnoses of either major depression or somatization disorder were given the MMPI. Women with somatization disorder had high scores on Keane's MMPI scale (PK) for posttraumatic stress disorder. Following the procedure for the MMPI-2 (46 of the 49 PK items and MMPI-2 norms), 59% of the women with somatization disorder and 21% of the women with major depression would have T scores > or = 65 on the MMPI-2 scale although none of them were known to have developed psychiatric disorder after exposure to a life threatening event. The PK scale has little use in the differential diagnosis of women patients with somatization disorder.     

Intelligence and personality in mate choice and marital satisfaction

This research examined how intellectual and personality similarity or complementarity between a couple relates to their marital choice and marital satisfaction. Eighty-one couples were tested using the WAIS-R and the MMPI and the Locke-Wallace Marital Adjustment Scale. As predicted, couples showed significant similarity for some IQ variables. However, the prediction that IQ would have a relationship to marital satisfaction was not borne out. Couples show some significant similarity on some personality variables but for different variables in the 39 Clinic couples and the 42 Non-clinic couples. A strong relationship was found between couples in both samples on the Pd scale. As far as marital satisfaction is concerned, similarity or complementarity in personality variables does not appear.     

What to Do When Evidence-Based Treatment Manuals Are Not Enough? Adapting Evidence-Based Psychological Interventions for Primary Care

Significant barriers exist in accessing high-quality, evidence-based psychological interventions in traditional mental health settings. Adapting these interventions for delivery within primary care is particularly advantageous given that the majority of individuals with mental health conditions are more likely to seek care in this environment much earlier in their course of illness than in specialty mental health clinics. The aim of this paper is to summarize efforts at Mayo Clinic to develop and disseminate evidence-based psychological interventions across multiple primary care clinics. Adaptations aimed at improving access to care, enhancing the quality of care, and incorporating a system of measurement-based outcomes are unique features that are essential to the sustainability and advancement of integrated behavioral health programs within primary care.     

A Psychometric Investigation of the Suicide Status Form II with a Psychiatric Inpatient Sample

We investigated the psychometric validity and reliability of the Suicide Status Form‐II (SSF‐II) developed by Jobes, Jacoby, Cimbolic, and Hustead (1997) . Participants were 149 psychiatric inpatients (108 suicidal; 41 nonsuicidal) at the Mayo Clinic. Each participant completed assessment measures within 24 hours of admission and 48–72 hours later. Factor analyses of the SSF core assessment produced a robust two‐factor solution reflecting chronic and acute response styles. The SSF core assessment had good to excellent convergent and criterion validity; pre‐post SSF ratings also demonstrated moderate test‐retest reliability. The results replicated previous research and show that the SSF‐II is psychometrically sound with a high‐risk suicidal inpatient sample.     

MMPI ratings of suicide risk.

Among past attempts to use MMPI data to predict suicidal behavior, there has been a lack of research on the ability of clinicians to identify MMPI profiles of suicidal persons. In this study, the MMPI profiles of 20 male psychiatric patients who committed suicide and the MMPI profiles of 20 male patients who did not attempt or commit suicide were presented to six clinical psychologists with expertise in MMPI interpretation. The clinicians were asked to classify each MMPI profile as coming from a patient who did or did not later commit suicide, and to rate eight variables thought to be relevant to the assessment of suicide risk. Data analysis revealed that the clinicians could not identify suicide and nonsuicide patients from their MMPI profiles. Furthermore, the ratings of the eight suicide variable did not differentiate suicide and nonsuicide patients.     

Social desirability and Wiggin's MMPI content scales.

Using the Minnesota Multiphasic Personality Inventory (MMPI) item pool, Wiggins (1966) developed 13 scales, each with a homogeneous content. The 13 scales, along with marker scales for the 1st 3 MMPI factors, Edward's social desirability (SD), Welsh's repression (R), and Wiggins's social desirability (Sd) respectively were scored in the MMPI. The same scales were scored in an Experimental Multiphasic Personality Inventory (EMPI). A principal-components analysis of the 16 scales when scored in the MMPI resulted in 4 factors. A principal-components analysis of these same scales when scored in the MMPI and when scored in the EMPI were found to be highly congruent. The SD, R, and Sd scales proved to be excellent markers for the 1st 3 factors of the MMPI and also for the 1st 3 factors of the EMPI. Results provide further evidence that the 1st MMPI factor is a social desirability factor rather than a content factor.     

Parent and child MMPI responses: Characteristics among families with adolescents in inpatient and outpatient settings

The relationship of parent personality to child psychopathology has been investigated in numerous MMPI studies over the past three decades. Very few of these studies, however, have directly analyzed MMPI response patterns of both parents and offspring. The current study included the MMPI responses of 199 families with adolescents entering inpatient and outpatient psychiatric setting (N = 542). Inpatient parents and adolescents had significantly higher mean scores across a variety of MMPI scales than did their outpatient counterparts. The linear combination of adolescent and maternal MMPI scale data, in a stepwise discriminative function analysis, resulted in accurate classification of 75% of all children in inpatient treatment and 74% of all children assigned to outpatient treatment. Findings were discussed in terms of salient MMPI differences between inpatient and outpatient families and shared psychopathological characteristics among family members with offspring in psychiatric treatment settings.     

Utility of the MMPI in a geriatric population

Despite the popularity of the Minnesota Multiphasic Personality Inventory (MMPI), there exists a relative dearth of normative and validity research regarding its use with persons over the age of 60. Our investigation was designed to examine the MMPI performance of both a normal and a clinical sample of older men and women. Specifically, a nonpatient community sample of 204 subjects and an outpatient psychiatric sample of 30 subjects, between the ages of 60 and 90, were administered the MMPI as well as structured psychiatric interview, the Psychiatric Status Schedule (PSS). Results revealed that, on most of the MMPI scales, the mean scores were well above the norms (i.e., 5-10 t-score points). Through comparisons between the clinical and community subjects as well as between MMPI and PSS performance, the MMPI demonstrated substantial discriminative and concurrent criterion validity within this geriatric sample. The results of the study suggest that, with a few important exceptions, the MMPI, as generally utilized, is valid for use in the geriatric population.     

Rorschach movement and color responses and MMPI social extraversion and thinking introversion personality types

Results of an analysis of MMPI profiles and Rorschach protocols scored by the Exner method for 100 psychiatric patients provided partial support for Rorschach's hypotheses that perceptions of color (FC, CF, and C) and movement (M) tap separate personality dimensions. First, the proportion of M responses on a protocol correlated significantly (p < .01) to thinking introversion as defined in terms of a subject's MMPI profile similarity to a prototypic MMPI profile with peak PtSc elevations. Second, the proportion of FC responses correlated negatively (p < .01) to social extraversion defined in terms of MMPI profile similarity to a prototypic MMPI profile with peak PdMa elevations. Hence, use of FC signified a socially reserved, controlled behavior. The findings regarding CF and C were inconclusive. Third, color and movement responses did not correlate significantly with somatization defined in terms of similarity to a prototypic MMPI profile with peak Hs, D, Hy elevations. Finally, the nonsignificant correlations of FC with M and with MMPI thinking introversion plus the nonsignificant correlation of M with color responses and MMPI social extroversion further supported the hypotheses that movement and color responses tap essentially unique personality dimensions.     

Validation of an MMPI short form with literate and illiterate patients

An Improved Readability Form (IRF) of the MMPI was orally administered to 100 literate and 119 illiterate patients, and 140 literate patients were given the full MMPI with standard instructions. Profile comparisons of the MMPI with the IRF given to literates or extracted from the full MMPI yielded only small differences. The much larger differences in the IRF profiles of the illiterates were removed by controlling statistically for sex, race, age, and education. The IRF, when given to literate patients, was a good substitute for the full MMPI in predicting Brief Psychiatric Rating Scale scores. For the illiterates, the two most salient relationships with scores on the Brief Psychiatric Rating Scale were preserved, but several weaker associations were qualitatively altered. When the IRF is administered to illiterate patients, the pattern of clinical correlates may differ from those obtained with literate patients given the IRF or MMPI.     

Utility of the MMPI in a Geriatric Population

Despite the popularity of the Minnesota Multiphasic Personality inventory (MMPI), there exists a relative dearth of normative and validity research regarding its use with persons over the age of 60. Our investigation was designed to examine the MMPI performance of both a normal and a clinical sample of older men and women. Specifically, a nonpatient community sample of 204 subjects and an outpatient psychiatric sample of 30 subjects, between the ages of 60 and 90, were administered the MMPI as well as a structured psychiatric interview, the Psychiatric Status Schedule (PSS). Results revealed that, on most of the MMPI scales, the mean scores were well above the norms (i.e., 5-10 t-score points), Through comparisons between the clinical and community subjects as well as between MMPI and PSS performance, the MMPI demonstrated substantial discriminative and concurrent criterion validity within this geriatric sample. The results of the study suggest that, with a few important exceptions, the MMPI, as generally utilized, is valid for use in the geriatric population.     

Whither goest our redoubtable mentor, the MMPI/MMPI-2?

Four areas of MMPI use and development toward the year 2000 and beyond are discussed. First, although the MMPI-2 booklet is a clear improvement, we will continue to need to use both profiles, the MMPI-2 for normative purposes and the MMPI profile for pattern interpretation. Applying MMPI expectations to MMPI-2 profiles is a violation of Meehl's basic actuarial prediction concepts. Secondly, as psychologists begin prescribing medications, we may be able to substantially refine drug choices. Thirdly, the measurement of socioeconomic status levels appears to be the major, missing moderator variable in MMPI/MMPI-2 interpretation. Lastly, an effective and positive MMPI/MMPI-2 feedback paradigm is discussed that fits well within the managed care context.     

Using the MMPI–2–RF to Discriminate Psychometrically Identified Schizotypic College Students From a Matched Comparison Sample

This study investigates the extent to which the Minnesota Multiphasic Personality Inventory–2 Restructured Form (MMPI–2–RF) profiles of 52 individuals making up a psychometrically identified schizotypes (SZT) sample could be successfully discriminated from the protocols of 52 individuals in a matched comparison (MC) sample. Replication analyses were performed with an additional 53 pairs of SZT and MC participants. Results showed significant differences in mean T-score values between these 2 groups across a variety of MMPI–2–RF scales. Results from discriminant function analyses indicate that schizotypy can be predicted effectively using 4 MMPI–2–RF scales and that this method of classification held up on replication. Additional results demonstrated that these MMPI–2–RF scales nominally outperformed MMPI–2 scales suggested by previous research as being indicative of schizophrenia liability. Directions for future research with the MMPI–2–RF are suggested.     

MMPI scale development methodology

A multitude of special MMPI scales have been developed without sufficient consideration for the methodology of empirical scale construction. Suggestions are presented in this article regarding the selection of items for a new MMPI scale and the tasks needed for the evaluation of a new scale. An investigator who develops a new MMPI scale should consider (a) the need for K corrections of scale scores, and (b) the possibility that the information provided by the special scale can also be obtained from the standard MMPI scales.     

Clinical Considerations in the Conjoint Use of the Rorschach and the MMPI

Contemporary clinical and research findings concerning the Rorschach and the Minnesota Multiphasic Personality Inventory (MMPI) indicate that (a) objectivity and subjectivity are relative and not categorical dimensions of these two instruments; (b) apparent contradictions between Rorschach and MMPI results are generative and not invalidating; (c) within limits, false negative findings are not cause for concern in the clinical application of Rorschach and MMPI variables; and (d) differences between the Rorschach and the MMPI in how they are structured and what they measure demonstrate considerable advantage in using them in complementary fashion to support clinical inferences.     

Diagnostic Accuracy of the MMPI–2 Malingering Discriminant Function Index in the Detection of Malingering Among Inmates

The MMPI–2 Malingering Discriminant Function Index (M-DFI) was designed to detect malingerers educated about MMPI–2 validity indicators. However, given current attorney practices, the clinical utility of the M-DFI lies in its ability to detect examinees who are cautioned about the indicators. In this study, we compared 45 inmate simulators cautioned to avoid detection on the MMPI–2 with 46 psychiatric inmates who completed the MMPI–2 under standard instructions. Logistic regression analyses indicated that although the M-DFI performed better than several individual indicators, results were mixed for combinations of indicators, and the M-DFI did not outperform different sets of existing indicators. These findings support existing strategies to detect malingering on the MMPI–2. We discuss considerations concerning the clinical applicability of M-DFI.