Minnesota Multiphasic Personality Inventory-2: An Evaluation Of The Strengths And Weaknesses Of The Testing Instrument. 201e6c

Running head: MINNESOTA MULTIPHASIC PERSONALITY INVENTORY-2

Minnesota Multiphasic Personality Inventory-2 Tammy Daniel Coles Walden University

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Abstract The MMPI-2 is an assessment tool that is very popular with psychologists and clinicians alike. It is one of the most widely used assessments, but isn’t often critically evaluated in clinical practice. It is a strong assessment tool with comprehensive empirical , but it also has substantial weaknesses in both research and practice that make it difficult to qualify using for the general population. It is one of a battery of assessments that make up good clinical practice and can be used as one of the tools to diagnose a client, but should not be used as the only tool in practice.

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Minnesota Multiphasic Personality Inventory-2 The Minnesota Multiphasic Personality Inventory-2 (MMPI-2) is the current revision of the Minnesota Multiphasic Personality Inventory. The MMPI-2 is a clinical testing instrument that is a 567-item self-reported personality inventory that is used in evaluation and diagnosis of psychological conditions (Gregory, 2011). There has been a lot of debate regarding the MMPI-2 and its validity, especially in the early stages of the instrument’s development. Although the initial Minnesota Multiphasic Personality Inventory (MMPI) was a well-developed and strictly empirically based inventory, there was a great deal of difficulty finding a publisher for the assessment. Despite the difficulties with the introduction of the MMPI, by 1982 the personality inventory became the 2nd most popular psychological assessment used by clinicians. Hathaway, McKinley & Butcher (1990) call the rise of the MMPI phenomenal, adding that a 1978 study found that 84% of all psychological research surrounding personality used the MMPI as the primary assessment tool (Hathaway, McKinley & Butcher, 1990). Given all of the research and development, the more current revision of the MMPI, the MMPI-2 has become the standard for personality assessment in clinical practice. In this paper, we review the history, the psychometric qualities, the strengths and weaknesses of the instrument, and how the MMPI-2 can be best used in a counseling practice. Theoretically the MMPI-2 is one of the best testing instruments available for clinicians to establish empirically based differential diagnoses with psychiatric clients. Although it doesn’t directly align with diagnostic codes found in the DSM-IV TR, it is a favorite tool of clinicians worldwide. The use of the MMPI-2 in a counseling practice to help evaluate personality disorders has become a professional standard in the psychological profession. That familiarity and commonality makes the MMPI-2 a tool that

MINNESOTA MULTIPHASIC PERSONALITY INVENTORY-2 needs to be researched and reviewed. Often times, when something in a professional field of

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study becomes standard and familiar, it is no longer subject to the critical evaluation that newer assessments face. The goal of this paper is to further critical evaluation of the MMPI-2 in an effort to limit professional acquiescence related to using familiar assessments blindly in a clinical practice. MMPI-II History The MMPI-2 is the 1989 revision of the original MMPI. The original MMPI was developed to provide a self-report method for assessing psychopathology (Maruish, 2004). Published in 1943 by Stark Hathaway and J.C. McKinley, the MMPI quickly became one of the top 20 assessments used in professional practice (Hathaway, McKinley & Butcher, 1990). The original personality inventory consisted of 566-item true-false questions and measured 10 clinical scales (Gregory, 2011). Amongst those scales, Drayton (2009) suggests that the real purpose of the assessment was to help distinguish those with psychiatric conditions from the “normals” by creating scales of normalcy (Drayton, 2009). The original MMPI assessment faced a great deal of criticism, because the initial control group consisted only of relatives and visitors to medical patients at the University of Minnesota Hospital. All of the control subjects were White/Caucasian, young (approx. average age 35), married and from a small town or rural area in Minnesota (Gregory, 2011). Although the control group was large enough to be a valid sample (724 subjects), the lack of diversity or homogenization in the sample demonstrates a major weakness in the validity of the test. The chosen sample was clearly not representative of the general population in the United States. Another issue with the MMPI that raised concern was the individual item content of the assessment. Gregory conveys that there were many obsolete archaic and offensive used in

MINNESOTA MULTIPHASIC PERSONALITY INVENTORY-2 the original assessment. There were references to games and slang terminology that is not

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familiar in modern times. The MMPI also included sexist language and many Christian religious references that were sources of lawsuits and privacy concerns when istered to modern subjects (Gregory, 2011). In 1989, the revised and standardized MMPI-2 was released. The revision worked to correct many of the weaknesses of the original assessment including eliminating some scales and updating the item content. The goal of the revision was to make the assessment stronger without sacrificing the original empirical strength. According to Maurish, the major change with in the items on the MMPI-2 was the deletion of 13 items that contained objectionable or outdated content. Another change that Maurish discusses is the new content scales that were developed for the MMPI-2. The new scales were devised in order to offer clinicians an empirical and rational scale to help standardize test interpretation (Maruish, 2004). Drayton provides further for this interpretation change and concludes that the MMPI-2 revision has limited clinician’s assumptions in favor empirically ed interpretation guidelines (Drayton, 2009). By reducing or eliminating result assumptions, scoring the assessment could become more standardized and hence empirically stronger. Psychometric Qualities In of standardization, reliability, and validity, The MMPI-2 has been thoroughly investigated. The MMPI-2 consists of 567 true/false items. The inventory is a self-report measure of an individual’s psychopathology. The assessment has nine validity scales built in. These scales assess for lying, defensiveness, and faking good or bad answers. There is also a symptom validity scale designed to exclude symptom exaggeration and reduce false-positive rates. Drayton points out that these scales make it very difficult for results to be faked (Drayton, 2009). Helmes (2008)

MINNESOTA MULTIPHASIC PERSONALITY INVENTORY-2 6 on the other hand, is concerned about the underreporting of skipped items on the inventory and issues of acquiescence. He points out that there is a great deal of research about “faking” answers, but very little in regards to inconsistent or random response. Helmes criticizes the validity scales that are sensitive to content nonresponsiveness (CNR) because they may not be sensitive enough to detect individual sections of the assessment that were completed at random versus. He argues that the CNR scales are only designed to detect when the entire inventory is completed with random response patterns (Helmes, 2008). The MMPI-2 is designed for adults, but adolescents may be tested as well. The inventory requires a 6th grade reading level and generally takes individuals between 1 and 1 ½ hours to complete (Gregory, 2011). Nichols and Kaufman point out that the MMPI-2 testing manual recommends an 8th grade reading level and that many items on scale 9 of the test require a 9th grade reading level (Nichols & Kaufman, 2011). This high reading level is one of biggest weaknesses in of format for the MMPI-2. According the U.S. Department of Education (2007), the average reading score for adults in the United States is around mid-7th grade level (U.S. Department of Education, 2007). This evidence suggests that the MMPI-2 would not be appropriate for the general population. In of the incarcerated population, a U.S. Department of Education study found the average reading level to be about 5th grade (Kolstad, 1994.) Helmes points out that the test was not designed for use with offenders and this evidence s his findings. The reading level of the MMPI-2 is high for the general population and given the prevalence of learning disabilities in the prison population, even the length of the test may make the MMPI-2 inappropriate for the population (Helmes, 2008). This concept of population exclusion comes as no surprise, because the MMPI-2 was validated in a study that used 2600 adults who were “loosely” representative of the general

MINNESOTA MULTIPHASIC PERSONALITY INVENTORY-2 population. A major weakness that Gregory points out with this sample is that higher

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educational levels are overrepresented (Gregory, 2011). Rushton and Irwing these findings. Rushton and Irwin go beyond Gregory in order to demonstrate additional issues with the chosen 2600 adult sample including an underrepresentation of Hispanics and Asian-Americans and an overrepresentation of college educated and higher socioeconomic groups (Rushton & Irwing, 2009). In of the incarcerated offender population, this evidence s Helmes arguments that the sample utilized is not representative of the prison population and hence the MMPI-2 may be more difficult to validate when used in forensic assessment of prison populations (Helmes, 2008). Cultural Concerns Cultural concerns are a major issue with standardized testing and the original MMPI items showed significant cultural bias (Gregory, 2011). The revised MMPI-2 used a more representative sample of the general population and demonstrates a major improvement in lessening cultural bias issues (Maurish, 2004). A study of African American individuals found no significant evidence of testing bias with the MMPI-2. The research conducted by McNulty, Graham, Ben-Porath & Stein (1997) did find major differences in the comparison of results for African American and Caucasian participants. Mcnulty et al. found that African American men scored significantly higher on the Lie scale and Fears content scale than did their Caucasian counterparts. The research also found that African American women scored higher than Caucasian women on Hypomania and that Caucasian women scored higher on the Low Self Esteem content scale. McNulty et al. attribute this discrepancy to actual client psychopathology as opposed to test bias. McNulty found correlations between the MMPI-2 and patient descriptions were not significantly different and found no evidence of testing bias based on results (McNulty,

MINNESOTA MULTIPHASIC PERSONALITY INVENTORY-2 8 Graham, Ben-Porath & Stein, 1997). The same couldn’t be said when comparing the results of adult men and women. Blaha, Merydith, Wallbrown and Dowd (2001) found that Scale 3 was significantly different when comparing men and women (Blaha, Merydith, Wallbrown & Dowd, 2001). These findings are preliminary and conducted only in an initial study. This means further research is necessary to decipher if the discrepancy is due to an issue of test bias or rather is the result of actual client psychopathology. Test istration Specifics that Nichols and Kaufman suggest that will greatly improve the overall validity of individual assessments include the examiner’s ability to build a strong rapport with participants, his or her ability to assess the examinees willingness, his or her affiliation to a third party test requester, his or her ability to provide a proper practical overview and the examiner’s ability to recognize sensory, motor, and learning barriers prior to istration (Nichols & Kaufman, 2011). A well-trained examiner is key to ensuring a valid and proper assessment. The istration of the MMPI-2 is actually quite complex, despite common misconceptions regarding the ease of test istration. Nichols and Kaufman believe that test s that are well trained and are able to build a good rapport with test takers are essential to ensuring a valid test result (Nichols & Kaufman, 2011). One other concern regarding test istration is istering individual scales out of context. This is becoming more common in of the Post Traumatic Stress Disorder (PTSD) Scale and MacAndrew Alcoholism Scale being used independently and out of context. Butcher, Graham and Ben-Porath (1995) suggest several problems that arise when scales are istered separately. The first problem they discuss is the istration of highly similar items with obvious content that are istered together in close sequence. Butcher et al. warn that this

MINNESOTA MULTIPHASIC PERSONALITY INVENTORY-2 type of testing method can alter the mental set of the participant. In plain language, the lack of

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variability in the assessment may incline a participant to answer differently during this type of istration than from that during the completion of the entire MMPI-2, in which the items are intermingled together. Butcher et al. suggest that altered stimuli (i.e., only the Depression scale items) could produce a different response attitude than if all of the items had been istered. The examinee may be influenced to answer questions in a different way, hence biasing the results (Butcher, Graham & Ben-Porath, 1995). Another problem associated with extracted scales is that the researchers may not able to examine the MMPI-2 validity scales to exclude invalid data from their studies (Butcher, Graham & Ben-Porath, 1995). Without the validity scales in place, the participant could potentially “fake” or randomize their answers undetected, giving an invalid result. All the data seems to suggest that istering scales individually ultimately sacrifices the validity of the results. Validity and Reliability Validity is one of the largest strengths of the MMPI-2. Butcher, Mineka and Hooley (2010) this by calling the MMPI-2 the most validated and widely adaptable personality test available (Butcher, Mineka & Hooley, 2010). A great deal of research suggests that the validity scales built into the assessment adequately correct for many of the potential issues that can bias subject results. On the inverse, reliability is one of the biggest weaknesses of the MMPI-2 (Nichols & Kaufman, 2011). In of reliability, Vacha-Haase, Kogan, Tani, Woodall and Thompson (2001) argue that tests aren’t reliable. Vacha-Haase et al. attribute this to score variability and sample composition. Both of these influence reliability, causing changes across istration. Looking at the data, the reliability coefficient of the MMPI-2 statistically falls below generally accepted levels, showing the reliability the MMPI-2 to be very low (Vacha-

MINNESOTA MULTIPHASIC PERSONALITY INVENTORY-2 Haase, Kogan, Tani, Woodall & Thompson, 2001). In most scientific studies, this would

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invalidate the results. In a self-report psychological inventory, the results can’t be measured as rigorously and multiple istrations are often a more effective way to validate reliable results. Vacha-Haase, Henson and Caruso (2002) argue for the use of Reliability Generalization in of assessing this type of test reliability. Vacha-Hasse’s suggests that her model of score reliability is a more effective validation method for this type of assessment, because it relies on multiple istrations as opposed to the traditional test/retest scientific methodology (Vacha-Haase, Henson & Caruso, 2002). Looking at the issue of validity, Meyer et al. (2001) argue that the validity of psychological tests is comparable to the validity of medical tests. In of client knowledge in a clinical practice, Meyer et al. maintain that the best knowledge is obtained from the sophisticated integration of information derived from a multimethod assessment battery even in the absence of the hard empirical data that many scientific studies look for (Meyer et al., 2001). The validity of the MMPI-2 is one of the assessments strengths and the build in validity scales are an essential part of the empirical evidence that suggests that the MMPI-2 is one of the stronger personality assessment tools available in clinical practice. MMPI-2 Critique Some of the greatest strengths of the MMPI-2 include validity and versatility. As we discussed in the last section, in of validity, the greatest strength of the MMPI-2 lies in the nine validity scales that are built-in to assessment instrument. A small study that consisted of 74 individuals conducted by Arbisi and Ben-Porath (1998) found that the validity scales were very successful in detecting “fake bad” participant responses when participants tried to outsmart the assessment (Arbisi & Ben-Porath, 1998). In of overreporting or “fake good” responses,

MINNESOTA MULTIPHASIC PERSONALITY INVENTORY-2 11 Sellbom and Bagby (2010) found the MMPI-2 to also be successful in differentiating between individuals who were asked to overreport mental health problems and patients with genuine psychopathology. The validity scales were able to detect patterns regardless of whether dissimulating individuals had been coached (Sellbom & Bagby, 2010). Sellbom and Bagby’s finding are ed by the results of a study conduced by Tolin, Steenkamp, Marx and Litz. (2010). Tolin et al. found that symptom exaggeration could be adequately detected using the validity scales with veterans being evaluated for PTSD (Tolin, Steenkamp, Marx & Litz, 2010). Derksen (2006) points to the self-reporting format of the MMPI-2 as a benefit in getting accurate and honest responses from participants and the validity scales help ensure that underreported, overreported, and acquiescence are adequately detected (Derksen, 2006). In of versatility, the MMPI-2 has many different faucets. Looking at istration, the MMPI-2 can be istered in a clinical setting with a traditional pen and paper format, on a computer, or even sent home with a trusted client (Forbey and Ben-Porath, 2007). In of formats for different cultures and languages, Zapata-Sola, Kreuch,, Landers, Hoyt and Butcher (2009) found that Spanish-Speaking participant taking a Spanish Language version of the MMPI2 had scores that were highly similar to English-Speaking Participants taking an English Language version of the same MMPI-2 (Zapata-Sola, Kreuch, Landers, Hoyt, & Butcher, 2009). This evidence serves to further the versatility of the MMPI-2 and the ability of the assessment to be istered in different formats and languages without sacrificing the standardization, reliability, or integrity of the test. Helmes and Reddon (1993) point to some of the weaknesses of the MMPI-2. Earlier on we discussed reading level comprehension issues with the MMPI-2 assessment. Helmes and Reddon take the argument a bit further to point out that obsolete and cumbersome language still remains

MINNESOTA MULTIPHASIC PERSONALITY INVENTORY-2 12 in the current revision of the MMPI-2. Helmes and Reddon also point out that the scales of the assessment are of unbalanced lengths and that there is a high prevalence of unscored items. With approximately 30% of the questions unscored, Helmes and Reddon argue for their omission from the test (Helmes & Reddon, 1993). Helmes and Reddon also argue for more balanced items for each scale. One major weakness Pinsoneault (2007) points out is that the MMPI-2 still retains a level of insensitivity to random answers. While overall the MMPI-2 performed well, the validity scales failed to detect 37% of the items that scored ≥80 on the Variable Response Inconsistency scale (Pinsoneault, 2007). This means that if a majority of the assessment had random answers, the Validity Scales were able to detect them, but if items in one or two scales were answered randomly, than the Validity Scales may not be sensitive enough to detect them. This could cause issues in a participant’s ability to bias the exam results. MMPI-2 Use In A Counseling Setting In of using the MMPI-2 in a counseling practice, the findings suggest that the MMPI-2 should be used as a supplementary tool in conjunction with a battery of other comprehensive tests. The MMPI-2 is a very similar assessment to the MMPI, but isn’t equivalent (Bolinskey & Nichols, 2011). The MMPI-2 also doesn’t directly correlate with diagnoses found in the DSM-IV TR. In a counseling setting, the MMPI-2 would best be utilized to help map patterns of more or less disturbed personality traits and behavioral styles for different individuals as opposed to establishing differential diagnoses (Derksen, 2006). As a clinician, it is important to be properly trained in the istration of the MMPI-2 in order ensure the validity of results and limit both intentional and unintentional examiner bias (Nichols & Kaufman, 2011). Under the APA Code of Ethics, Psychologists do not promote the use of psychological assessment

MINNESOTA MULTIPHASIC PERSONALITY INVENTORY-2 13 techniques by unqualified persons (A.P.A., 2010). As a clinician in a counseling practice, it is important to insure that anyone istering the MMPI-2 is properly trained, and that includes yourself. Discussion and Conclusion The findings of this paper the importance of really critically evaluating any testing instrument that you choose to utilize with clients. Looking at the MMPI-2, it is a very strong instrument, well rooted in empirical research. That said, the MMPI-2 still has many weaknesses in of it being an assessment tool. Looking at the history of the MMPI-2, it has undergone many revisions and has been revised again since the 1989 creation of the MMPI-2. Each revision is intended to make the testing instrument stronger, but not equivalent to the previous edition of the test. Keeping issues of reading comprehension and proper testing istration in mind should help ensure valid results that will provide accurate information about a client’s psychopathology. It is important to that there isn’t one all-inclusive personality assessment tool that will give a comprehensive picture of an individual’s personality. Proper diagnoses require a comprehensive assessment using a battery of tests as to ensure that the results are accurate and in the client’s best interest. Staying up-to-date on current testing practices and critically evaluating commonly used assessments is important to serving psychiatric clients well.

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