The Truth About Myers-Briggs Types

The Myers-Briggs Type Indicator (MBTI) is the most widely administered psychological test. In all likelihood, most of you have taken it once, if not more than once.

The Myers-Brigg typology is based on Jung’s theory of psychological types. It was constructed by the mother and daughter team of Katherine Cook Briggs and Isabel Briggs Myers. Katherine Briggs had used Jungian notions of personality to analyze characters in literature. Although the MBTI is based on Jungian theory, it was really Isabel Myers’ interpretation of that theory that lies beneath the test’s construction.

For example, in Jung’s theory, there is no “judging-perception” dimension (J vs. P), that was a creation of Myers and Briggs. So, there are problems with both the theory and the construction of the MBTI. Unfortunately, Myers and Briggs were not very good at test construction and psychometrics.

Either, Or, or Both?

There are serious psychometric problems associated with the MBTI. For example, one problem that afflicts all typologies is that scores are put into categories. In other words, you are either an Extravert (“E”) or an Introvert (“I). In actuality, personality dimensions are continuous, with persons being more or less extraverted or introverted.

In addition, the MBTI has a forced-choice format that requires you to choose between an Extraversion or an Introversion item, (or a Thinking versus a Feeling item, etc.). Your score and your type are based on how many of each you choose. So, you could choose 11 Extraversion items and 9 Introversion items and be an “E,” while another “E” might have 20 Extraversion items and zero Introversion. Yet, you are given the same “score.”

I’ve had many people who have taken the MBTI on multiple occasions wonder why their types change with each administration. Why, if personality is relatively stable? The scoring creates an additional problem as during one test administration you might score an “E” (11 vs. 9), and the next time, by only changing two items, you become an “I” (9 vs. 11). This is one reason with there is low test-retest reliability in the MBTI.

Problems With How the MBTI Is Used

The MBTI has been used, or I should say misused, in many ways. For example, in premarital counseling, the MBTI has been used to gauge the “compatibility” of couples. There is really no evidence to support this use.

I have also heard of companies that use the MBTI to select employees. This is an obvious misuse because there is no evidence to support the accuracy of MBTI types in hiring.

More commonly, the MBTI is used in career advising (e.g., suggesting that Thinking types go into more structured jobs; Extraverts into “people professions,” etc.). This also can be problematic because there is little evidence to support the connections between MBTI types and success in specific careers.

So, MBTI. What Is It Good For?

Perhaps the best use for the MBTI is for self-reflection. If used as a starting point for discussing how people vary in their personalities, and emphasizing tolerance for individual differences and taking others’ perspectives, then it can be a useful tool. However, it is important that the test administrator caution against over-interpretation of the results, and discuss the limitations of the instrument.

For good, detailed criticisms of the MBTI, please see the references.