Minnesota Multiphasic Personality Inventory (MMPI)

The term MMPI in personality assessment refers to the Minnesota Multiphasic Personality Inventory. This standardized psychometric test identifies personal, social, and behavioral issues in psychiatric patients.

History of the MMPI

The Minnesota Multiphasic Personality Inventory (MMPI) is probably the most widely used multidimensional tool to help diagnose mental health disorders. This test was first developed in 1939 by clinical psychologist Starke Hathaway and neuropsychiatrist J.C. McKinley at the University of Minnesota, and it was first published in 1943.

This tool is unique. It was created to measure psychopathology specifically, not to assess personality in general.

To develop it, the team constructed clinical scales endorsed by patients who had been diagnosed with certain mental disorders (Hathaway & McKinley, 1940).

Unlike other personality tests, the MMPI was not based on any particular prevailing theories about personality, such as the five-factor model or 16 personalities. It simply measures where someone falls on 10 clinical scales. Clinicians use those scores to diagnose the patient and select the proper treatment they need.

The MMPI developed from hundreds of true/false questions that were felt would be useful in identifying personality dimensions. These questions were then given to people suffering from a variety of psychological disorders and to a group that did not suffer from any disorder.

They then compared the two groups’ answers. Questions that most people with a particular illness answered differently from those identified as normal were kept.

Consequently, if a person answered many questions the way paranoid people did, it was highly likely that the individual was also paranoid.

How the Test Has Changed

Although this atheoretical approach allowed the MMPI to meaningfully capture traits that were directly related to psychopathology, the initial version was widely criticized.

Specifically, the original control group had a very small sample size, and it was primarily young, white, and married people from the rural Midwest.

Additionally, the MMPI was attacked for using incorrect terminology and not including a wide enough range of mental health issues, such as suicidal tendencies and drug abuse (Gregory, 2004).
As a result, the MMPI went through multiple stages of revision.

Administration

The MMPI-2 restandardization includes 567 items and takes approximately 60 to 90 minutes to complete. Like the MMPI, it has 10 clinical scales, each with roughly 32 to 78 items.

Who Administers the MMPI and Why

The vast majority of people obtain a few scores on each scale. Those administering the test are looking for a higher-than-average score on a scale to indicate a potential problem.

The MMPI is copyrighted by the University of Minnesota, so clinicians must pay to administer and use it.

The MMPI can only be administered and interpreted by psychologists who have been extensively trained in it. It can be done online or with a physical booklet.

After a participant takes the test, an evaluator prepares an interpretative report based on their responses.

Scoring: T-Scores and Codetypes

Raw scores are converted into normalized T-scores, ranging from 30 to 120, with a population average of 50. On the modern forms, a T-score of around 65 and above is treated as clinically significant (Framingham, 2016).

Over time, a set of standard clinical profiles, or “codetypes,” have emerged. A codetype is when two clinical scales have high T-scores.

For example, a 2-7 codetype means a participant scored high on both scale 2 (depression) and scale 7 (psychasthenia or OCD), signaling both depression and anxiety. Many common codetypes like this one have been identified and are well understood by clinicians.

The MMPI-2 is never administered in a vacuum: a participant’s background is taken into account, and it is typically not the only evaluative tool a person is given. Even so, it remains a valuable tool for identifying psychopathology.

10 Clinical Scales

The MMPI is designed to evaluate the thoughts, feelings, attitudes, and behaviors that make up an individual’s personality.

The test is administered by a trained clinician, typically a psychologist or psychiatrist, who relies on a series of clinical scales to interpret the results (Framingham, 2016).

These clinical scales help illustrate certain forms of psychopathology that an individual may have. The 10 clinical scales are as follows:

1. Hypochondriasis (Hs): excessive concern about bodily complaints, typically focused on the back and abdomen, that persist even when medical tests are negative. A high score suggests health worry is interfering with daily life and relationships. 32 items.
2. Depression (D): clinical depression marked by low morale, hopelessness, loss of interest in activities, worthlessness, and poor concentration. 57 items.
3. Hysteria (Hy): reactions to stress shown through physical complaints and denial of problems, examined across poor physical health, shyness, cynicism, and headaches. 60 items.
4. Psychopathic Deviate (Pd): social maladjustment and rule-breaking, including conflict with family and authority figures, self- and social alienation, and boredom. A high score may indicate antisocial tendencies. 50 items.
5. Masculinity/Femininity (Mf): interests, hobbies, and aesthetic preferences historically keyed to how closely a person conforms to stereotyped masculine or feminine roles. 56 items.
6. Paranoia (Pa): interpersonal sensitivity, moral self-righteousness, and suspiciousness, including delusional thoughts, grandiose thinking, and feelings of persecution at the extreme. 40 items.
7. Psychasthenia (Pt): an outdated term for what is now called obsessive-compulsive disorder (OCD), covering compulsive behaviors, abnormal fears, self-criticism, and anxiety. 48 items.
8. Schizophrenia (Sc): unusual thinking and perception, social alienation, and difficulty concentrating; it has the greatest number of items of any scale. It indexes deviant experience rather than diagnosing the disorder outright. 78 items.
9. Hypomania (Ma): elevated, unstable mood, psychomotor overactivity, impulsivity, rapid speech, and irritability. 46 items.
10. Social Introversion (Si): tendency toward social withdrawal versus outgoing sociability, including competitiveness, compliance, and timidity. Added later than the original nine scales. 69 items.

Together, these 10 dimensions comprise the clinical scales of the MMPI. Although there are many supplementary scales, these are the main 10 that guide a clinician’s evaluation of an individual. However, to accompany these 10 scales, a series of validity scales are also used to ensure the accuracy of the results.

Validity Scales

Validity refers to how accurately a method is actually measuring what it intends to measure. A common analogy for validity involves a dart board.

If all of the arrows are close to the bullseye, that is an example of strong validity because all of the arrows are close to what they are supposed to be close to. Even if some are slightly too high and some are slightly too low, if all of the arrows are close to the middle, that indicates high validity.

For the MMPI, there are not only studies that investigate the validity of the MMPI as a tool, but the instrument itself has its own validity scales to ensure that the test taker’s answers aren’t over-reported, under-reported, or flat out dishonest. In other words, the following scales help ensure that the respondent’s answers reflect what they should actually be reflecting (Framingham, 2016):

1. Lie (L): flags attempts to look unrealistically good by denying common, minor faults nearly everyone admits to. This scale contains 15 items.
2. F: flags rare, unusual, or symptom-heavy answers, which may reflect genuine severe disturbance, random responding, or an attempt to “fake bad.” This scale contains 60 items.
3. Back F (Fb): the same idea as the F scale, but scored from items in the second half of the test, to catch fatigue or a change in response pattern partway through. This scale has 40 items.
4. K: a subtler defensiveness index than L, measuring self-control and guarded self-presentation; in some scales it statistically corrects clinical scores upward. This scale is composed of 30 items.
5. Cannot Say (?): counts how many items a person leaves unanswered or marks both true and false. More than 30 unanswered items may invalidate the profile.
6. TRIN and VRIN: catch careless or contradictory answering. TRIN (True Response Inconsistency) flags an indiscriminate tendency to answer all true or all false; VRIN (Variable Response Inconsistency) flags random, inconsistent answers to similar item pairs.
7. Fp: separates genuine severe pathology from exaggeration by using items rare even among psychiatric patients, not just the general population. This scale has 27 items.
8. FBS: also called the Fake Bad Scale or Symptom Validity Scale; designed to detect intentional over-reporting of symptoms, mainly in personal-injury and disability cases. This scale has 43 items.
9. S: the Superlative Self-Presentation scale, used mainly in non-clinical settings like employment screening, measuring positive self-presentation through 50 questions about serenity, morality, and patience.

Empirical Studies Validating MMPI

As mentioned, high validity occurs when a tool measures what it claims to be measuring. So, in the case of the MMPI, high validity means that this inventory is actually measuring different types of psychopathology as it claims to be.

Take someone diagnosed with depression through other means. If the MMPI also revealed depressive traits in that individual, it would be deemed valid.

Conveniently, validity can be tested empirically. Several research studies have sought to examine the degree to which the MMPI is actually a valid tool.

The most-cited evidence on MMPI validity is a 1999 meta-analysis comparing it with the Rorschach inkblot test (Hiller et al., 1999).

Aim: to estimate and compare the criterion validity of the MMPI and the Rorschach across the published literature. This tested a common assumption. Is the objective MMPI necessarily more valid than the projective Rorschach?

Method: the researchers synthesised validity coefficients from many studies correlating each instrument’s scores with outcomes. A coefficient of 0.21 to 0.35 is labeled useful.

Results: the two instruments produced comparable average validity coefficients. The MMPI averaged 0.3 and the Rorschach 0.29. The MMPI had larger coefficients for studies using psychiatric diagnoses and self-report measures, while the Rorschach scored higher on studies using objective criterion variables.

Conclusion: the MMPI is a valid instrument, but its validity is moderate and roughly on par with a well-scored Rorschach. A coefficient near 0.3 means the test carries real, useful information while leaving much unexplained. So a profile is one input, not a verdict.

Another study measured the extent to which the MMPI can discriminate between sex offenders and controls.

In the study, 479 men took the MMPI and were scored on scales measuring sexual behavior and deviance, substance abuse, personality, violence, and more.

The MMPI screened sex offenders better than chance. This supports its validity as a tool for correctly identifying sex offenders (Langevin et al., 1990).

Some studies even test the validity scales themselves. For example, one study looked at the validity of the FBS scale which is used to identify individuals who are over-reporting somatic symptoms.

The researchers measured associations between scores on the MMPI-FBS scale and a symptom validity test (SVT) in 127 criminal defendants and 141 civil claimants.

The researchers found that scores on the FBS were, in fact, associated with SVT failure (incorrectly reporting symptoms) in both the criminal and civil defendants (Wygant et al., 2007).

This supports the FBS’s utility. It flags inaccurate reporting of both somatic and cognitive complaints.

Another study observed the validity of the F and Fp scales in detecting psychopathology in a criminal forensic setting.

One hundred twenty-five criminal defendants were given a Structured Interview of Reported Symptoms (SIRS) and the MMPI-2 RF. The two MMPI-2 RF over-reporting scales properly differentiated between defendants who were genuinely ill and those who were faking it, supporting the scales’ validity (Sellbom et al., 2010).

Together, these studies show the MMPI-2 is valid. Not only does it have validity scales in place, but these scales themselves are valid too.

Having this kind of confirmation allows this tool to be viewed as highly credible and effective by the research world.

Empirical Research

Research on the MMPI-2 extends beyond validity testing. Several studies have examined the tool across different settings and populations, from clinical samples to college students to workplaces.

Clinical and Occupational Populations

One study relied on the MMPI-2 to identify key disorders among battered women in transition. Of the 31 women evaluated, 90% scored high on the psychopathy, paranoia, and schizophrenia scales (Khan et al., 1993).

The MMPI-2 thus guides both diagnosis and intervention.

A separate study examined the workplace, where bullying, defined as exposure to psychological violence and harassment, places an unnecessary strain on employees and their productivity. Researchers used the MMPI-2 to identify psychological correlates of bullying among 85 former and current victims.

Bullied victims showed an elevated MMPI-2 profile, and the profile’s shape tracked the type and intensity of bullying they experienced (Matthiesen & Einarsen, 2001).

A further study looked at a different population: college students. Researchers administered the MMPI-2 to 515 male and 797 female college students across four universities.

The group responded to the test much like the normative sample, supporting the idea that the MMPI-2’s norms generalize to college populations (Butcher et al., 1990).

These are just a couple of examples from an expansive research literature: researchers have targeted varying populations, settings, and even different versions of the test.

Critical Evaluation

Although the MMPI-2 is a widely used and highly valid test, it does not come without its criticisms. Here are the three main concerns raised about it:

1. Cultural and Demographic Bias: non-white respondents score higher on average across many scales, a pattern traced to the test’s original, mostly white and Minnesotan reference groups, not to real differences in psychopathology (McCreary & Padilla, 1977).
2. FBS Validity Controversy: Butcher and colleagues argue the Fake Bad Scale doesn’t cleanly measure over-reporting and can be biased against women, people with disabilities or trauma histories, and psychiatric inpatients (Butcher et al., 2008).
3. RF vs. MMPI-2 Debate: Butcher and Williams argue the shorter MMPI-2-RF isn’t a safe substitute for the MMPI-2 in high-stakes evaluations like child custody, though critics call their examples cherry-picked (Butcher & Williams, 2012).

Cultural and Demographic Bias

Studies of incarcerated people, medical patients, and high school students have repeatedly found that Black and other non-white respondents score higher than white respondents across many clinical scales. The gap runs several T-score points on average (McCreary & Padilla, 1977).

Applied uncritically at a fixed cut-score, that pattern risks over-diagnosing minority respondents with psychopathology they don’t actually have.

The likely explanation lies in how the test was built. Empirical keying bakes the response tendencies of the original criterion and normative groups directly into the scales.

Those groups were drawn almost entirely from a white, rural Minnesotan population of the 1930s and 1940s.

Later re-norming, including the MMPI-2’s larger and more diverse standardization sample, has reduced the disparity but not eliminated it. The concern is most consequential precisely where the MMPI is common: high-stakes forensic and employment evaluations.

FBS Validity Controversy

Butcher, Gass, Cumella, Kally, and Williams (2008) criticize the FBS, or Fake Bad Scale, on two separate grounds: psychometric and fairness.

It was later renamed the Symptom Validity Scale. Psychometrically, they argue it does not cleanly isolate over-reporting from other causes of an elevated score.

They also say the criteria used to define malingering, exaggerating or feigning illness, are not consistently replicable across studies.

On fairness, they argue the scale can be biased against women, trauma survivors, and people with genuine disabilities or medical illness.

Real symptoms may inflate the scale just as faking would.

Because the FBS is widely used to flag symptom exaggeration in personal-injury litigation, a validity scale that mislabels genuine sufferers as fakers is not a minor technicality.

It can affect who receives compensation, treatment, or credibility in a legal proceeding.

RF vs. MMPI-2 Debate

In a separate paper, Butcher and Williams (2012) argue the shorter MMPI-2-RF is not a viable replacement for the MMPI-2 in high-stakes evaluations such as child custody.

The restructured scales, they say, lose information that the longer instrument’s decades of interpretive research still carry. Many forensic and custody evaluators continue to prefer the MMPI-2 over the RF for exactly this reason.

However, the scientific community has pushed back hard against Butcher and Williams’ specific critique, calling it misleading and its examples cherry-picked rather than representative.

The debate illustrates a broader tension in the MMPI’s history. Each revision gains construct clarity and efficiency, but has to earn its place against an older form’s accumulated evidentiary weight before clinicians and courts fully adopt it.

Contemporary Research

The strongest recent evidence on the MMPI concerns its signature capability: detecting when a respondent is distorting their answers. This might mean exaggerating symptoms (over-reporting, “faking bad”) or minimizing them (under-reporting, “faking good”).

This matters most in high-stakes settings where a person has an incentive to distort, including personal-injury litigation and pre-employment screening.

Aim: a meta-analysis by Ingram and Ternes (2016) set out to quantify how well the MMPI-2-RF’s five over-reporting validity scales distinguish honest responders from people feigning or exaggerating symptoms. It also tested what moderates that performance.

Method: the researchers located 25 experimental and quasi-experimental studies comparing validity-scale scores between honest and over-reporting groups, then ran moderated meta-analyses testing several moderators.

Results: every over-reporting scale was an effective general discriminator, with mean effect sizes ranging from about 1.08 (Symptom Validity, FBS-r) to about 1.43 (Infrequent Psychopathology, Fp-r). Fp-r and the response-bias scale were the least affected by moderating factors, and the honest-versus-feigning separation was narrower than traditional cut-scores imply.

Conclusion: the RF validity scales reliably detect patterned over-reporting. Their thresholds should be applied with attention to base rates and the evaluation context rather than mechanically (Ingram & Ternes, 2016).

Known-groups studies in criminal-forensic settings reach the same conclusion using real evaluees, not instructed simulators (Sellbom et al., 2010).

Studies linking MMPI-2 validity scores to independent symptom-validity tests agree. The same numerical elevation carries different weight in a treatment-seeking clinic than in a compensation-seeking forensic referral (Wygant et al., 2007).

Together, these converging designs make response-validity assessment the MMPI’s best-replicated contemporary contribution: not diagnosis itself, but telling the clinician how much to trust the rest of the profile.

In general, despite these open questions about bias and interpretation, the MMPI-2 remains widely accepted by the scientific community.

FAQs

References

Ben-Porath, Y. S. (2012). Interpreting the MMPI-2-RF. Minneapolis: University of Minnesota Press.

Ben-Porath, Y. S., & Tellegen, A. (2008/2011). MMPI-2-RF (Minnesota Multiphasic Personality Inventory-2 Restructured Form) manual for administration, scoring, and interpretation. Minneapolis: University of Minnesota Press.

Ben-Porath, Y. S., & Tellegen, A. (2008). Empirical correlates of the MMPI–2 Restructured Clinical (RC) scales in mental health, forensic, and nonclinical settings: An Introduction. Journal of Personality Assessment, 90(2), 119-121.

Brown, J. R., Menton, W. H., & Ben-Porath, Y. S. (2024). Development and validation of a method for deriving MMPI-3 scores from MMPI-2/MMPI-2-RF item responses. Psychological Assessment, 36(11), 665-679. https://doi.org/10.1037/pas0001341

Butcher, J. N., Gass, C. S., Cumella, E., Kally, Z., & Williams, C. L. (2008). Potential for bias in MMPI-2 assessments using the Fake Bad Scale (FBS). Psychological Injury and Law, 1(3), 191-209.

Butcher, J. N., Graham, J. R., Dahlstrom, W. G., & Bowman, E. (1990). The MMPI-2 with college students. Journal of Personality Assessment, 54(1-2), 1-15.

Butcher, J. N., & Williams, C. L. (2009). Personality assessment with the MMPI‐2: Historical roots, international adaptations, and current challenges. Applied Psychology: Health and Well‐Being, 1(1), 105-135.

Butcher, J. N., & Williams, C. L. (2012). Problems with using the MMPI–2–RF in forensic evaluations: A clarification to Ellis. Journal of Child Custody, 9(4), 217-222.

Framingham, J. (2016). Minnesota Multiphasic personality Inventory (MMPI). Retrieved from https://psychcentral.com/lib/minnesota-multiphasic-personality-inventory-mmpi#What-Does-the-MMPI-2-Test?

Gregory, R. J. (2004). Psychological testing: History, principles, and applications. Allyn & Bacon.

Handel, R. W. (2016). An introduction to the Minnesota multiphasic personality inventory-adolescent-restructured form (MMPI-A-RF). Journal of clinical psychology in medical settings, 23(4), 361-373.

Hathaway, S. R., & McKinley, J. C. (1940). A multiphasic personality schedule (Minnesota): I. Construction of the schedule. The Journal of Psychology, 10(2), 249-254.

Hathaway, S. R., & McKinley J. C. (1942). Manual for the Minnesota Multiphasic Personality Inventory. Minneapolis: University of Minnesota Press.

Hathaway, S. R., & McKinley, J. C. (1943). The MMPI. Minneapolis.

Hiller, J. B., Rosenthal, R., Bornstein, R. F., Berry, D. T., & Brunell-Neuleib, S. (1999). A comparative meta-analysis of Rorschach and MMPI validity. Psychological Assessment, 11(3), 278.

Ingram, P. B., & Ternes, M. S. (2016). The detection of content-based invalid responding: A meta-analysis of the MMPI-2-Restructured Form’s (MMPI-2-RF) over-reporting validity scales. The Clinical Neuropsychologist, 30(4), 473-496. https://doi.org/10.1080/13854046.2016.1187769

Kaemmer, B. (1992). Minnesota Multiphasic Personality Inventory-Adolescent Version (MMPI-A): Manual for administration, scoring and interpretation.

Khan, F. I., Welch, T. L., & Zillmer, E. A. (1993). MMPI-2 profiles of battered women in transition. Journal of Personality Assessment, 60(1), 100-111.

Langevin, R., Wright, P., & Handy, L. (1990). Use of the MMPI and its derived scales with sex offenders: I. Reliability and validity studies. Annals of Sex Research, 3(3), 245-291.

Matthiesen, S. B., & Einarsen, S. (2001). MMPI-2 configurations among victims of bullying at work. European Journal of work and organizational Psychology, 10(4), 467-484.

Sellbom, M., Toomey, J. A., Wygant, D. B., Kucharski, L. T., & Duncan, S. (2010). Utility of the MMPI–2-RF (Restructured Form) validity scales in detecting malingering in a criminal forensic setting: A known-groups design. Psychological Assessment, 22(1), 22.

McCreary, C., & Padilla, E. (1977). MMPI differences among black, Mexican‐American, and white male offenders. Journal of Clinical Psychology, 33(S1), 171-177.

Tellegen, A., Ben-Porath, Y. S., McNulty, J. L., Arbisi, P. A., Graham, J. R., & Kaemmer, B. (2003). MMPI-2 Restructured Clinical (RC) scales: Development, validation, and interpretation.

Tellegen, A., & Ben-Porath, Y. S. (2008/2011). MMPI-2-RF (Minnesota Multiphasic Personality Inventory-2 Restructured Form) technical manual. Minneapolis. University of Minnesota Press.

Tupes, E. C., & Christal, R. E. (1992). Recurrent personality factors based on trait ratings. Journal of personality, 60(2), 225-251.

Whitcomb, S., & Merrell, K. W. (2013). Behavioral, social, and emotional assessment of children and adolescents. Routledge.

Wygant, D. B., Sellbom, M., Ben-Porath, Y. S., Stafford, K. P., Freeman, D. B., & Heilbronner, R. L. (2007). The relation between symptom validity testing and MMPI-2 scores as a function of forensic evaluation context. Archives of Clinical Neuropsychology, 22(4), 489-499.

Further Reading

• Interpretation of MMPI-2 Clinical Scales. MMPI-2 Training Slides, Univerity of Minnesota Press; 2015.
• Interpretation of MMPI-2 Validity Scales. MMPI-2 Training Slides, Univerity of Minnesota Press; 2015.
• Ben-Porath YS, Tellegen A. MMPI-3: Manual for Administration, Scoring, and Interpretation. Pearson; 2020.
• Floyd AE, Gupta V. Minnesota Multiphasic Personality Inventory. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing. Updated May 1, 2021.