The Minnesota Multiphasic Personality Inventory (MMPI) is a standardized psychometric test of adult personality and psychopathology. A version for adolescents also exists, the MMPI-A, which was first published in 1992. Psychologists use various versions of the MMPI to help develop treatment plans, assist with differential diagnosis, help answer legal questions (forensic psychology), screen job candidates during the personnel selection process, or as part of a therapeutic assessment procedure.

The original MMPI was developed by Starke R. Hathaway and J. C. McKinley, faculty of the University of Minnesota, and first published by the University of Minnesota Press in 1943. It was replaced by an updated version, the MMPI-2, in 1989 (Butcher, Dahlstrom, Graham, Tellegen, and Kaemmer). An alternative version of the test, the MMPI-2 Restructured Form (MMPI-2-RF), published in 2008, retains some aspects of the traditional MMPI assessment strategy, but adopts a different theoretical approach to personality test development. The newest version (MMPI-3) was released in 2020.

History The original authors of the MMPI were American psychologist Starke R. Hathaway and American neurologist J. C. McKinley. The MMPI is copyrighted by the University of Minnesota.

The MMPI was designed as an adult measure of psychopathology and personality structure in 1939. Many additions and changes to the measure have been made over time to improve interpretability of the original clinical scales. Additionally, there have been changes in the number of items in the measure, and other adjustments which reflect its current use as a tool towards modern psychopathy and personality disorders. The most historically significant developmental changes include:

In 1989, the MMPI became the MMPI-2 as a result of a restandardization project to develop a new set of normative data representing current population characteristics; the restandardization increased the size of the normative database to include a wide range of clinical and non-clinical samples; psychometric characteristics of the clinical scales were not addressed at that time.Butcher, J. N., Dahlstrom, W. G., Graham, J. R., Tellegen, A, & Kaemmer, B. (1989).The Minnesota Multiphasic Personality Inventory-2 (MMPI-2): Manual for administration and scoring. Minneapolis, MN: University of Minnesota Press. In 2003, the Restructured Clinical scales were added to the published MMPI-2, representing a reconstruction of the original clinical scales designed to address known psychometric flaws in the original clinical scales that unnecessarily complicated their interpretability and validity, but could not be addressed at the same time as the restandardization process.Tellegen, A., Ben-Porath, Y.S., McNulty, J.L., Arbisi, P.A., Graham, J.R., & Kaemmer, B. (2003). The MMPI-2 Restructured Clinical Scales: Development, validation, and interpretation. Minneapolis, MN: University of Minnesota Press. Specifically, Demoralization – a non-specific distress component thought to impair the discriminant validity of many self-report measures of psychopathology – was identified and removed from the original clinical scales. Restructuring the clinical scales was the initial step toward addressing the remaining psychometric and theoretical problems of the MMPI-2. In 2008, the MMPI-2-RF (Restructured Form) was published to psychometrically and theoretically fine-tune the measure.Ben-Porath, Y.S. (2012). Interpreting the MMPI-2-RF. Minneapolis: University of Minnesota Press. The MMPI-2-RF contains 338 items, contains 9 validity and 42 homogeneous substantive scales, and allows for a straightforward interpretation strategy. The MMPI-2-RF was constructed using a similar rationale used to create the Restructured Clinical (RC) scales. The rest of the measure was developed utilizing statistical analysis techniques that produced the RC scales as well as a hierarchical set of scales similar to contemporary models of psychopathology to inform the overall measure reorganization. The entire measure reconstruction was accomplished using the original 567 items contained in the MMPI-2 item pool. The MMPI-2 Restandardization norms were used to validate the MMPI-2-RF; over 53,000 correlations based on more than 600 reference criteria are available in the MMPI-2-RF Technical Manual for the purpose of comparing the validity and reliability of MMPI-2-RF scales with those of the MMPI-2.Tellegen, A., & Ben-Porath, Y. S. (2008). MMPI-2-RF (Minnesota Multiphasic Personality Inventory-2 Restructured Form): Technical manual. Minneapolis: University of Minnesota Press. Across multiple studies and as supported in the technical manual, the MMPI-2-RF performs as good as or, in many cases, better than the MMPI-2. The MMPI-2-RF is a streamlined measure. Retaining only 338 of the original 567 items, its hierarchical scale structure provides non-redundant information across 51 scales that are easily interpretable. Validity scales were retained (revised), two new validity scales have been added (Fs in 2008 and RBS in 2011), and there are new scales that capture somatic complaints. All of the MMPI-2-RF's scales demonstrate either increased or equivalent construct and criterion validity compared to their MMPI-2 counterparts.Ben-Porath, Y. S., & Tellegen, A. (2008). MMPI-2-RF (Minnesota Multiphasic Personality Inventory-2 Restructured Form): Manual for administration, scoring, and interpretation. Minneapolis: University of Minnesota Press.

Current versions of the test (MMPI-2 and MMPI-2-RF) can be completed on optical scan forms or administered directly to individuals on the computer. The MMPI-2 can generate a Score Report or an Extended Score Report, which includes the Restructured Clinical scales from which the Restructured Form was later developed. The MMPI-2 Extended Score Report includes scores on the original clinical scales as well as Content, Supplementary, and other subscales of potential interest to clinicians. Additionally, the MMPI-2-RF computer scoring offers an option for the administrator to select a specific reference group with which to contrast and compare an individual's obtained scores; comparison groups include clinical, non-clinical, medical, forensic, and pre-employment settings, to name a few. The newest version of the Pearson Q-Local computer scoring program offers the option of converting MMPI-2 data into MMPI-2-RF reports as well as numerous other new features. Use of the MMPI is tightly controlled. Any clinician using the MMPI is required to meet specific test publisher requirements in terms of training and experience, must pay for all administration materials including the annual computer scoring license and is charged for each report generated by computer.

In 2018, the University of Minnesota Press commissioned development of the MMPI-3, which was to be based in part on the MMPI-2-RF and include updated normative data. It was published in December 2020.University of Minnesota Press, Test Division, MMPI-3 Development Update (December 2019).

MMPI

The original MMPI was developed on a scale-by-scale basis in the late 1930s and early 1940s. Hathaway and McKinley used an empirical [criterion] keying approach, with clinical scales derived by selecting items that were endorsed by patients known to have been diagnosed with certain pathologies.Hathaway, S. R., & McKinley, J. C. (1940). A multiphasic personality schedule(Minnesota): I. Construction of the schedule. Journal of Psychology, 10, 249-254.Hathaway, S. R., & McKinley, J. C. (1942). A multiphasic personality schedule (Minnesota): III. The measurement of symptomatic depression. Journal of Psychology, 14, 73-84.McKinley, J. C, & Hathaway, S. R. (1940). A multiphasic personality schedule (Minnesota): II. A differential study of hypochondriasis. Journal of Psychology, 10,255-268.McKinley, J. C, & Hathaway, S. R. (1942). A multiphasic personality schedule (Minnesota): IV. Psychasthenia. Journal of Applied Psychology, 26, 614-624.McKinley, J. C, & Hathaway, S. R. (1944). A multiphasic personality schedule (Minnesota): V. Hysteria, Hypomania, and Psychopathic Deviate. Journal of Applied Psychology, 28, 153-174. The difference between this approach and other test development strategies used around that time was that it was in many ways atheoretical (not based on any particular theory) and thus the initial test was not aligned with the prevailing psychodynamic theories. Theory in some ways affected the development process, if only because the candidate test items and patient groups on which scales were developed were affected by prevailing personality and psychopathological theories of the time. The approach to MMPI development ostensibly enabled the test to capture aspects of human psychopathology that were recognizable and meaningful, despite changes in clinical theories. However, the MMPI had flaws of validity that were soon apparent and could not be overlooked indefinitely. The control group for its original testing consisted of a small number of individuals, mostly young, white, and married men and women from rural areas of the Midwest. (The racial makeup of the respondents reflected the ethnic makeup of that time and place.) The MMPI also faced problems as to its terminology and its irrelevance to the population that the test was intended to measure. It became necessary for the MMPI to measure a more diverse number of potential mental health problems, such as "suicidal tendencies, drug abuse, and treatment-related behaviors."

MMPI-2

The first major revision of the MMPI was the MMPI-2, which was standardized on a new national sample of adults in the United States and released in 1989. The new standardization was based on 2,600 individuals from a more representative background than the MMPI. It is appropriate for use with adults 18 and over. Subsequent revisions of certain test elements have been published, and a wide variety of sub scales were introduced over many years to help clinicians interpret the results of the original 10 clinical scales. The current MMPI-2 has 567 items, and usually takes between one and two hours to complete depending on reading level. It is designed to require a 4.6 grade (Flesh-Kincaid) reading level. There is an infrequently used abbreviated form of the test that consists of the MMPI-2's first 370 items. The shorter version has been mainly used in circumstances that have not allowed the full version to be completed (e.g., illness or time pressure), but the scores available on the shorter version are not as extensive as those available in the 567-item version. The original form of the MMPI-2 is the third most frequently utilized test in the field of psychology, behind the most used IQ and achievement tests.

MMPI-A

A version of the test designed for adolescents ages 14 to 18, the MMPI-A, was released in 1992. The youth version was developed to improve measurement of personality, behavior difficulties, and psychopathology among adolescents. It addressed limitations of using the original MMPI among adolescent populations.Butcher, J.N., Williams, C.L., Graham, J.R., Archer, R.P., Tellegen, A., Ben-Porath, Y.S., & Kaemmer, B. (1992). Minnesota Multiphasic Personality Inventory-Adolescent Version(MMPI-A): Manual for administration, scoring and interpretation. Minneapolis, MN: University of Minnesota Press. Twelve- to thirteen-year-old children were assessed and could not adequately understand the question content so the MMPI-A is not meant for children younger than 14. People who are 18 and no longer in high school may appropriately be tested with the MMPI-2.