Discussion of Personality Scales
Discussion of Personality Scales
University of Bridgeport
There are hundreds of options to evaluate one’s personality these days if you’re willing to pay $6.95 for the test results on the internet. However, how reliable and/or valid are these tests? Instead of choosing some random single trait test or a test that tell me what Disney villain I would closely identify with, I chose to try the Minnesota Multiphasic Personality Inventory. This test has gained respect over the years, but just because it is respected, does that mean it’s valid and reliable? Although it would have been interesting to gather informant data (I) by making my friends fill out this 567 true/false questionnaire on me I decided not to torture them for a few hours. To compare my self-reported data to informant data, I had two friends fill out the version of the Myers Briggs Personality Scale from 16personalities.com. Many of the results from both tests were surprising.
The Myers-Briggs is a typological personality assessment. This means that the test places individuals into very distinct categories versus placing them on a spectrum; an individual is either an extrovert or an introvert, thinking or feeling, intuitive or sensing, perceiving or sensing. The combination of these four categories implies that there are 16 distinct personality types. Although making distinctions this black and white has its advantages, people, in general, are not that simple. When I took the test, I was categorized as an ENFP (Extrovert, Intuitive, Feeling, Perceiving). The test has test re-test reliability because I received the same results at least one month apart. However, I had two friends take the test as if they were me and neither of them got the same results I did. Frankie, whom I spend time with on a regular basis, said I was INFP (Introvert, Intuitive, Feeling, Perceiving). Per, whom I used to spend time with but rarely see anymore, said I was an ENTP(Extrovert, Intuitive, Thinking, Perceiving). I found it
interesting that my friends perceive me differently than I perceive myself in addition to not being in agreeance with each other. This would imply that the convergent validity of the Myers-Briggs is low. According to Balsis et. al (2015), informant data is more internally consistent than self-reported data in personality assessment, but this internal consistency does not imply that the data is valid, just reliable. However, after having multiple informants for this examination of personality scales, internal consistency does not mean the test is reliable overall.
In addition to taking the Myers-Briggs, I took the MMPI. The MMPI is a multi-trait personality assessment that measures 10 major categories of clinically abnormal human behavior-hypochondriasis, depression, hysteria, psychopathic deviate, male/female roles, paranoia, psychasthenia, schizophrenia, hypomania, and social introversion. Interpreting the results of the MMPI is quite complicated. According to the validity scales built in, my responses were remarkably consistent and I did not overreport or underreport any symptoms. I apparently scored fairly high on the psycopathic deviate scale indicating that I am rebellious, non-conforming, impulsive, angry, irritable, dissatisfied, creative, underachiever, poor work history, and I have family problems (MMPI Training Slides, 2015). Investigating this scale further, the subscales indicate that I score highest in family discord and I have issues with authority. Looking at the initial score, one may assume that I have one of the cluster B personality disorders, but making this assumption would be inaccurate. After attempting to interpret my own results on this test, I realized how important it is to have training in interpreting someone’s MMPI score. The raw numbers may look like that indicate one thing or another, when in reality it does not.