History of the MMPI
According to Roger L. Greene (2011), the Minnesota Multiphasic Personality Inventory (MMPI), MMPI-2, and MMPI-2RF are the most widely used self-report measures of psychopathology. The history of the MMPI dates back to the early history of self-report personality inventories. Personality assessments had its first major stimulus during World War I when assessment procedures were needed to screen a large population. Woodworth and Poffenberger responded by developing the Woodworth Personal Data Sheet, which was designed to detect mental instability. This inventory, however, had no theoretical perspective or a systematic method for the selection the questions. Even so, the inventory did identify WWI recruits that would need to be further interviewed for sufficient mental stability to enlist for the army. Another early, well-known personality inventory similar to the Woodworth Personal Data Sheet is the Bernreuter Personality Inventory (Greene, 2011). This inventory started a trend to measure multiple dimensions of personality. Although heading in the right direction, the scale was critiqued and shown to be an invalid measure of personality. Most early personality inventories were generally unsuccessful due to the lack of empirical data and lack of validation. In the 1930s, Starke Hathaway and J. C. McKinley sought to develop a multifaceted inventory, now known as the MMPI, which would improve on the shortcomings of previous tests (Greene, 2011). Hathaway and McKinley created more than 1,000 items based on textbooks, previous personality inventories, and their own clinical experiences. Once their items were condensed to 504 items, the next step was to construct quantitative scales that could be used to measure various categories of psychopathology. Items chosen for each scale were based on an empirical approach, therefore the reason items were selected was because the criterion group answered them differently from other groups. The way the normative group was selected was based on who were friends and/or relatives of patients in the University Hospitals in Minneapolis. The only criterion that excluded individuals from being in the normative group was if they were already receiving psychiatric treatment. The primary normative group consisted of 742 individuals, and these individuals ranged from ages 16 to 55 and were mainly white. In the 1930s, there were very few ethnic minorities that resided in Minnesota. There were four additional normative groups that were used in developing the scales in the MMPI. These other norm groups were based on age, education, and socioeconomic class. Item selection was based on the frequency of “true” and “false” responses and then Z scores represented the significance of the difference between the two. It is important to note that Hathaway and McKinley were both aware of test-taking attitudes, and individuals may fail to provide an accurate self-report. There are many issues, such as interpreting a question different ways or answering the way an individual thinks a question should be answered, rather than how it actually reflects their own personality. Although these issues exist, the MMPI is still valid because the empirical approach makes no assumption of the client’s self-report and the client’s behavior. Items in each scale are only there because the criterion group answered the items differently than the normative group regardless if the content is an accurate description of the criterion group (Green, 2011).
MMPI Versus MMPI-2
Tests prior to the MMPI did not assess test-taking attitudes or provide information on whether or not certain attitudes were present. The MMPI validity scales addressed this problem. Meehl and Hathaway constructed three validity scales for the MMPI: The L, F, and K scales. The L scale is based on responding to an item that would give the client a favorable image and the probability that the response would be dishonest is high. The F scale was developed to address the possibility of test takers intentionally trying to deviate from the normative group (pretend a psychopathology). Third, the K scale was created to differentiate those with a known psychopathology with normal scores and those from normal population groups with elevated scores.
A big issue with the difference between the MMPI and the MMPI-2 was whether or not the items and norms for the MMPI were still valid and appropriate for contemporary use. Many assessments have been done comparing MMPI basic validity and clinical scales between current normative populations and the normative population used when the test was developed (Greene, 2011). Greene (2011) also compared samples of MMPI-2 codetypes to MMPI codetypes. The findings from these studies suggest that only minor changes have been made on the standard validity and clinical scales across 50 years. These findings also suggest that the MMPI may not be as outdated as many have thought. Even so, these changes were address and the restandardization of the MMPI resulted in the MMPI-2.
The restandardization of the MMPI, the MMPI-2, was much needed to provide current norms for the inventory. This led to the development of a national and larger normative sample, a better representation of ethnic minorities, and an update on item content where needed (Greene, 2011). Items on the validity and clinical scales are essentially the same between the MMPI and MMPI-2 except for the deletion of 13 items and the rewording of 68 items. The MMPI-2 was standardized from a sample of 2,600 individuals and reflected national census parameters. The MMPI normative sample is completely different from the MMPI-2 normative sample, which represents more minorities, a wider age, occupational, and education range, and a larger sample. A major change between the MMPI and MMPI-2 is the use of T scores in the MMPI-2, except for scale 5 (masculinity-femininity) and scale 0 (social introversion). Also, the MMPI-2, unlike the MMPI is used only with adults 18 years and older. Adolescents are tested with the MMPI-A, and adolescent version of the MMPI.
Clinical Scales There are 10 clinical scales in the MMPI-2 (Greene, 2011). Scale 1 (Hypochondriasis) includes 32 items that reflect a person’s preoccupation with physical complaints. Scale 2 (Depression) includes 57 items that are designed to assess depressed mood. Scale 3 (Hysteria) includes 60 items that deal with the clients specific physical complaints and denial of concern about the physical problems. Scale 4 (Psychopathic Deviate) includes 50 items that asses antisocial and a tendency to blame others for their problems. Scale 5 (Masculine-Feminine Interests) includes 56 items that measure stereotypic masculine and feminine interests. Scale 6 (Paranoia) includes 40 items that indicate feelings of suspiciousness of others. Scale 7 (Psychasthenia) includes 48 items concerned with feelings of anxiety and maladjustment. Scale 8 (Schizophrenia) includes 78 items that reflect feelings of alienation, confusion, and isolation. Scale 9 (Mania) includes 46 items that show excessive energy and scattered behavior. Scale 0 (Social Introversion-Extraversion) includes 69 items measuring social shyness and lack of social assertiveness. It is important that clinicians understand that the name given to each scale is based on type of clients that who were in that criterion group (Greene, 2011). When working with clients, the clinician does not refer to the actual name of the scale, just the numerical value of the scale.
Interpreting the MMPI-2 Interpretation of the MMPI-2 may be a daunting task for clinicians if they are not aware of the many issues with profile interpretation. First off, it is important to understand that the MMPI-2, like any other self-report, is based on the client’s self-report of behaviors and symptoms. This means that although a client may not fit the criteria for depression in the DSM, the client is reporting symptoms of depression. Statements that are made based on the MMPI-2 results are all hypotheses about the participant who took the assessment. If a client has elevated scores on scale 6 (paranoia), then an interpretation can be made that the client has paranoid symptoms, not that the client actually has the diagnosis. Like the mentality scientists should have when conducting experiments, clinicians should also have a disconfirming mentality when it comes to interpreting the MMPI-2. Greene (2011) warns clinicians although information in the MMPI-2 may lead to certain interpretations, it is still important to be alert for any information that is contradictory to their hypotheses. It is also important to note that the report of the MMPI-2 is not designed to be given directly to the clients. The interpretation of a MMPI-2 profile should be used as guidance and reference for future counseling sessions as well as developing possible treatment plans. Once the MMPI-2 has been scored, the interpretation process can begin (Greene, 2011). The first step involves interpreting the T scores on each scale. For example, if the T score for scale 1 is 75, this indicates that the score is marked and the clinician should take caution that this may be an indication the client has vague physical complaints. There are also certain patterns of elevated T scores that occur on the validity and clinical scales and can be interpreted that patients with specific disorders may fit the same T score pattern (Greene, 2011). The highest T scores are considered to be the client’s codetype, and there are correlates with those scales. Once all this information is processed, the information is used to complete the client’s profile.
Reliability and Validity The MMPI-2 was released in 1989 and revised in 2001, so even though the assessment is relatively new, much research has been conducted for reliability and validity purposes (Greene, 2011). Research by Putnam, Kurtz, and Houts (1996) is one example that illustrated the test-retest reliability of the MMPI-2. Participants consisted of 111 active male clergy and completed the MMPI-2 on two occasions separated by a 4 month time frame. The test-retest scores obtained in the study reflected similar results to those reported in the MMPI-2 manual. Other studies have also established the test’s reliability within in a short time frame (1 week) and long time frame (5 years) (Putnam et al., 1996). Another study focused on using the MMPI-2 with college students and the participants were compared to the MMPI-2 normative sample (Butcher, Graham, Dahlstrom, & Bowman, 1990). Results showed that mean score differences on the validity and clinical scales were within 1-3 T score points and the frequency distributions were also similar to the normative sample. The study also showed reliability on test-retest correlation coefficients. Validity is traditionally measured with the basis of to what degree does a test actually measure what it is intended to measure. This type of validity in relation to the MMPI-2 would be comparing the relationship of the overall test to an external factor such as psychiatric diagnosis. The MMPI-2 also has a second type of validity within the test itself. This type of validity of the MMPI-2 is assessed by three main categories: omission of items, consistency of item endorsement, and accuracy of item endorsement (Greene, 2011). The original validity scales have basically been kept the same with the addition of three new validity scales: the FB, VRIN, and TRIN. Thirty or more omitted items suggest that the test be considered invalid and not interpreted. The VRIN scale and the TRIN scale measure any response inconsistency. The VRIN indicates if a participant is responding inconsistently to items and the TRIN scale identifies if true or false responses are given randomly. The L, FB, K, and F scales measure the accuracy of item endorsement on the MMPI-2. These scales detect deviant responses, so the participant could be trying to give themselves a favorable view or in a severe pathological view.
It is widely accepted that the MMPI-2 is a useful resource for treatment planning and evaluation. Many studies have found evidence on the test’s ability to predict outcome of substance abuse treatment, general psychotherapy, pain rehabilitation programs, and accuracy of clinical judgments (Lima et. al, 2005). The original MMPI has been used for over 50 years, and within that time no revisions in item content was made. The MMPI-2 is evidence of a valid revision and expansion of the MMPI. Some of the complaints about the original MMPI were that items were out of date, sexist, or just plain awkward. The MMPI-2 addressed these complaints by establishing new normative groups as well as some item editing and deletion as mentioned before.
Discussion
Overall, the MMPI-2 is a great resource for clinicians and other mental health practitioners to use as an assessment of clients in a wide variety of settings. It continues to be a reliable and valid tool of assessment and there is even the MMPI-2RF, which consists of 338 items instead of 567 from the MMPI-2 (Greene, 2011). I believe that the MMPI-2 will continue to be used in the counseling profession because it not only gives counselors data to assess, but interpretation of the assessment gives more information and direction for the clinician to discuss with the client. I think one area of research that can still be expanded on is the use of the MMPI-2 with minorities. Even though the normative group for the MMPI-2 was a reflection of the census data when it was created, there is still not the greatest representation of minority groups. Research can be conducted comparing minority participants’ scores to the normative group data from the MMPI-2 manual to see if a similar relationship exists. There might also be some cross cultural factors that would affect the results if the test was given outside of the Western culture.

References Butcher, J. N., Graham, J. R., Dahlstrom, W. G., & Bowman, E. (1990). The MMPI-2 with college students. Journal of personality assessment, 54(2), 1-15. Green, R. L. (2011). The MMPI-2/MMPI-2-RF: An interpretive manual (3rd ed.). Boston, MA: Allyn & Bacon. Lima, E. N., Stanley, S., Kaboski, B., Reitzel, L. R., Richey, J. A., Castro, Y., Williams, F. M., Tannenbaum, K. R., Stellrecht, N. E., Jakobsons, L. J., Wingate, L. R., & Joiner, T. E. (2005). The incremental validity of the MMPI-2: When does therapist access not enhance treatment outcome? Psychological Assessment, 17, 462-468. Putman, S. H., Kurtz, J. E., & Houts, D. C. (1996). Four-month test-retest reliability of the MMPI-2 with normal male clergy. Journal of Personality Assessment, 67, 341-353.