Many of us have probably heard of MBTI; you take a test of 100 questions and the results determine your personality type. From whether you’re a “diplomat” or an “explorer”, or whether you have the same personality type as Michael Jackson, the results can be so interesting and attractive to some people (me included!).

Today, it is  considered one of the most accurate personality tests, explaining its success in companies and professional settings… but have you ever wondered about the quality of this personality test? What are its current criticisms in personality psychology? More interestingly, how could our natural human biases influence our misinterpretation of the results?  
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At the end of the article you can find the link to the test and the main take-away from this article! :)

This article will cover:

• What is MBTI?
• Criticisms: psychometric properties
• Criticisms: misinterpretations and biases

What is MBTI?

Also known as the Myers Briggs Type Indicator, the MBTI is an introspective self-report questionnaire that assesses how people perceive the world and make decisions to indicate their psychological tendencies or preferences[2]. The concept is based on Carl Jung’s theory, which posited that people experience the world using four psychological functions–sensation, intuition, feeling, and thinking [2,10]. The theory was further studied and extended by Katherine Cook Briggs and Isabel Briggs Myers, hence the name “Myers-Briggs”. Each function has a category, which are:

1. EXTRAVERSION / INTROVERSION - Briggs and Myers described extraversion and introversion in relevance to people’s preferred tendencies to “operate in the external world of behaviour, action, people, and things”, or “the internal world of ideas and introspection”, respectively [3,8]. When people use their preferred attitude, their energy tends to be more activated[3]. When one prefers extraversion, they expand energy from action, such as socialising and doing activities[10]. Therefore, they prefer to break away from further reflection to regain energy. When one prefers introversion, they look for inspiration and motivation from “alone time” as they reflect on their feelings and thoughts[3,8]. (“Energy” in this sense is vague, but what it generally refers to is the sense of motivation or stimulation. Basically, doing things that make you feel inspired[10]).  
   
   

2. SENSING / INTUITION - This cluster refers to people’s tendencies to gather and interpret information and knowledge. People with a preference to sensing tend to rely more on their senses for knowledge and interpretation. This includes information that is tangible, present, and concrete[3]. They prefer practical attention to details and facts and tend to avoid believing information that “comes out of nowhere”[10]. People with a preference for “intuition” prefer information less dependent on the senses, but more dependent on more abstract concepts and ideas[9]. They associate present information with other information such as remembered ideas or curious patterns[9]. They may be more interested in possibilities[3].

3. FEELING / THINKING - This cluster represents how people make decisions or come into conclusions after being presented with information[3]. Those with preference to “thinking” tend to make decisions by detaching themselves from the situation in order to think in a more analytical, logical and consistent way, pertaining to a set of rules[3,10]. Those with a preference to “feeling” take into consideration the people involved in the decision making process and themselves, empathising with the situation and attempting to set on a decision that benefits most parties[3.10]. They focus more on personal values while those who prefer “thinking” focus more on objective logic[10].

4. JUDGING / PERCEPTION - This was not posited by Jung, but later added by Briggs and Myers although its lack of evidence has been questioned[5]. This cluster refers to how people organise their environment and information[3]. Those who prefer “judging” tend to prefer structure and control, tending to “have matters settled”[10]. While those who prefer “perception” tend to keep an open and flexible approach to daily life, more often relying on spontaneity and flexibility[10].

Through our experiences and environment, it is believed that one quality from each category becomes more dominant throughout a person’s lifetime[9]. From these categories, the test yields 16 personality types (eg. an INFP personality type is one that includes Introversion, iNtuition, Feeling, and Perceiving).  

It is also important to mention that MBTI only measures our psychological tendencies, so it is impossible to only follow one function from a category [11]. A person who has a psychological tendency to “judging” can absolutely also act in a “perceiver” way from time to time!! Also, although our personality traits are relatively stable over time, they may also change through acquiring unique experiences[13]. For example, it was found that personality traits of elderly people (70 and above) are more likely to be less consistent than younger people[13]. Furthermore, it was also shown that people can slightly change their personality traits through longitudinal interventions[6].

Current criticisms: Psychometric properties

Although at face value the MBTI looks promising, it does have certain criticisms in personality psychology that are important to be considered. This is especially true in its psychometric properties.

Objectivity - The results of this personality test highly depend on participants’ honesty[1]. Unlike some other personality tests such as the Personality Assessment Inventory, MBTI does not use validity scales to assess exaggerated or socially desirable responses so it is not impossible for test-takers to fake their answers[1]. Therefore, there is a possibility that sometimes it may not give us objective answers, but answers that have been filtered to please test-takers’ perception of themselves. Of course, if you only intend to take the MBTI for entertainment purposes, this may not be a big problem, but if you were an HR specialist attempting to match employees’ personalities to well-suited jobs, this would be cause for concern.

Reliability - It has been shown that the test-retest reliability tends to be low[1](a high test-retest reliability refers to participants getting the same results in different situations and times[12]). An important factor in developing a good test is a high test-retest reliability so we can ensure that the test consistently measures personality, and not anything else, over time[12]. Although this can be permissible when the time difference between test-takings is years (as individuals could change their personality traits, but this change is gradual and slow), there is some evidence [7] that individuals would get a different answer if they retake the test after a 5-week gap.

A second criticism on reliability is that the test assumes mutually-exclusive categories. So it assumes that, or at least it lets the readers assume that they can only be one or the other. A consequence is that two people who behave similarly can be labelled differently (one introverted, and the other extraverted) [7].

Utility - MBTI is widely used in organisational settings, often in matching applicants to jobs based on their personalities[10]. This is often to ensure employee satisfaction and engagement, so to ensure that “jobs will be done properly and efficiently when rested on the suitable persons”[10]. However, some evidence showed that MBTI is a poor predictive validity for employees’ job performance ratings[9].

Myers also claimed that the personality of people varied according to their choice of study or field of work[2]. However, some researchers showed that the proportion of MBTI types according to their field of work or field of study is close to a random population, meaning that almost every personality type is represented equally[1].

Current criticisms: misinterpretations and biases

An interesting criticism of MBTI (and many other personality tests) is on how easily test takers can misinterpret the meaning of the test, and how our biases can play a role.

Barnum effect - The Barnum effect is the tendency for individuals to view general information, which is true about most people, to be an accurate description of themselves only[11]. This is possible because we are presented with different ways of conveying the same information, and we pick the ones that “feel” closest to our personality[11]. When we read the results of the test, the ambiguous and expressive language makes us susceptible to the Barnum effect, and we get excited about “how accurately it describes me!”. In reality, it may just be describing the tendency of most people.

I personally was very intrigued in how accurately the ISFP personality type described me. If you’re curious, read the description yourself and see how readers could easily fall into the Barnum effect!: https://www.16personalities.com/isfp-personality

Confirmation bias -This is a type of bias in which an individual selects information that confirms and further solidifies their prior beliefs[14]. If one fully believes that they have a particular MBTI type and is particularly pleased by its ambiguous results, they would take the test again and select answers that confirms evidence of the previously assigned type and be likely to ignore disconfirming evidence that runs contrary to your original type[4]. We do this because we have a tendency to think that our opinions are always correct, and disconfirming evidence makes us feel uncomfortable[14]. Likewise, since the MBTI has been very popular in entertainment such as memes which play on stereotypes of certain MBTI types, one may misinterpret what it actually means to “have” a certain MBTI type. The consequence is that one could simply feel that lately they’re in a stereotypically “INTJ” mood, and select answers that confirm this belief[5,11]. Therefore, the results would not give an objective representation of one’s personality type, but merely an instrument to further solidify bias to one personality type![5].

Fundamental attribution bias - This bias refers to our tendency to attribute other people’s behaviours on their internal characteristics, not on their environment[4]. As a simple example, we notice a fellow employee who almost always takes the leadership role in work events. We might attribute that to her personality but erase the possibility that she is only proactive at work but not in other activities. After being engrossed in personality tests, it can be argued that it becomes easier to think this way. Although in general this bias is not necessarily dangerous, consistently doing it means always attributing unlikeable behaviour to internal processes and it could make us less understanding and empathetic to people[4].

In conclusion, although the MBTI test gives fun and interesting results and can truly be informative to some of us, it is equally important to keep in mind the criticisms raised in personality psychology. This is especially relevant because many companies worldwide use this test for a variety of things such as assigning jobs to employees on the basis of their personality. Reading about criticisms would make us more critical of not only official personality tests, but also more simple, uncertified  online tests that claim to do wonderful things such as “determine whether you are emotional or logically oriented”.

What we should take from this article is that yes, the MBTI does yield quite “accurate” descriptions of who we are, but we shouldn't take them too literally as we may risk fulfilling our categories while we are much more flexible than we think! :)

To take the MBTI test, go to https://www.16personalities.com/free-personality-test

Enjoy discovering more about your personality, and keep in mind what you’ve learnt in this article!  

Additional sources:

1. Jung’s Theory of Personality https://www.youtube.com/watch?v=bP37RUJOzxI
2. Measuring personality-Crash Course psychology

https://www.youtube.com/watch?v=sUrV6oZ3zsk

References

1. Boyle, G. J. (1995). Myers-Briggs Type Indicator (MBTI): Some Psychometric Limitations. Australian Psychologist, 30(1), 71–74. https://doi.org/10.1111/j.1742-9544.1995.tb01750.x
2. Briggs, K., & Myers, I. (1998). MBTI manual : a guide to the development and use of the Myers-Briggs Type Indicator : Myers, Isabel Briggs : Free Download, Borrow, and Streaming : Internet Archive. https://archive.org/details/mbtimanualguidet00myer/page/n7/mode/2up
3. Dichotomies. (n.d.). Cpp.Edu. https://www.cpp.edu/%7Ecareer/mbti/dichotomies.html
4. Fuller, K. (2021, December 15). Personality Tests Exploit Cognitive Biases. . . But Why I’m Taking Them Anyways. Medium. https://medium.com/@kylie.fuller_/personality-tests-exploit-cognitive-biases-but-why-im-taking-them-anyways-a7114ff081c5
5. Hagler, T., & Hagler, T. (2017). Myers-Briggs and Other Pseudoscience. Trig. https://www.trig.com/tangents/myers-briggs-and-other-pseudoscience
6. Hudson, N. W., & Fraley, R. C. (2015). Volitional personality trait change: Can people choose to change their personality traits? Journal of Personality and Social Psychology, 109(3), 490–507. https://doi.org/10.1037/pspp0000021
7. Krznaric, R. (2014, October 23). Have we all been duped by the Myers-Briggs test? Fortune. https://fortune.com/2013/05/15/have-we-all-been-duped-by-the-myers-briggs-test/
8. MBTI ® – the Myers-Briggs Type Indicator. (n.d.). The Myers-Briggs. https://eu.themyersbriggs.com/en/tools/MBTI
9. Nowack, K. (1997). Personality Inventories: The Next Generation. Performance in practice. American Society of Training and Development, Winter 1996/97
10. The Myers & Briggs Foundation - MBTI® Basics. (n.d.). 2003–2022, The Myers and Briggs Foundation. https://www.myersbriggs.org/my-mbti-personality-type/mbti-basics/
11. Myers Briggs Criticisms. (n.d.). Team Technology. https://www.teamtechnology.co.uk/myers-briggs-criticisms.html
12. S. (2020, September 17). Test-Retest Reliability / Repeatability. Statistics How To. https://www.statisticshowto.com/test-retest-reliability/
13. Specht, J., Luhmann, M., & Geiser, C. (2014). On the Consistency of Personality Types Across Adulthood: Latent Profile Analyses in Two Large-Scale Panel Studies. SSRN Electronic Journal. https://doi.org/10.2139/ssrn.2501903
14. Why Do We Favor Information That Confirms Our Existing Beliefs? (2021, July 30). Verywell Mind. https://www.verywellmind.com/what-is-a-confirmation-bias-2795024