Myers-Briggs Type Indicator: A Vocational Assessment Review

Introduction to the MBTI

The Myers-Briggs Type Indicator (MBTI) is a personality assessment that can help guide people toward suitable vocations, though it is also useful in other contexts. It was developed by Isabel Briggs Myers and Katharine Cook Briggs from a Jungian psychology perspective. Although they began working on it in the early 1940s, it was first published in 1962. It is a self-report questionnaire that examines the individual's preferences along different components of personality. It was created for a normal population distribution and can be used by members of any demographic capable of processing the test, though it is probably most appropriate for late teens and beyond — perhaps age 14 and up.

The MBTI is a multiple-choice test written at a 7th-grade reading level. It takes approximately 20–30 minutes to administer, but the test is not timed; individual reading speed and decision time on each answer will affect total test-taking time.

The MBTI uses four pairs of contrasting traits to examine personality: extroversion–introversion (E-I), sensation–intuition (S-N), thinking–feeling (T-F), and judgment–perception (J-P). As a result of the interactions among these preferences, 16 distinctive personality types are identified by the instrument. The MBTI score also indicates the strength of preference for each dimension. Stronger scores indicate a greater likelihood that the individual has developed the attributes associated with those preferences (Fretwell et al., 2013).

Theoretical Framework and Scale Structure

The test is not looking specifically at vocational aptitudes; instead, it assesses broader personality characteristics that are then associated with success in, or aptitude for, certain types of vocations. The test's use of four scales is based on Carl Jung's theory of personality, which proposed four principal functions that affect an individual's perception and experience of the world: sensation, intuition, feeling, and thinking. The test places those functions on a continuum (sensation–intuition and feeling–thinking) and additionally examines introversion–extraversion and judging–perceiving.

The MBTI has been subjected to significant research over its lifetime and has been judged to be a reliable self-report inventory (Carlyn, 1977). However, there is some expert disagreement about the utility of the types described by the MBTI, leaving some researchers questioning what the test actually measures (Scott, 1999). "A latent trait/latent class analysis showed that at least three (the extraversion–introversion, thinking–feeling, and judgment–perception) of the four subscales were best conceptualized as a normally distributed latent trait" (Scott, 1999). In other words, if you plotted the subscale ends on a graph, you would see a roughly normal bell-shaped distribution, with smaller percentages of the population exhibiting traits strongly affiliated with either extreme and the majority of the population displaying some combination of those traits.

The test appears to be a valid measure of personality as defined by the instrument and by Jungian psychology, but whether those underlying concepts are themselves valid remains debatable. The MBTI does appear to be reliable in that it does not examine mood but rather underlying personality traits, and it demonstrates high test-retest reliability — suggesting that it successfully measures stable personality characteristics rather than transient mood states.

Reliability and Validity

The test itself is relatively simple. It can be administered in almost any environment, and many universities, colleges, and even high schools offer routine free or reduced-cost MBTI screening to interested students. It can be administered via paper and pencil or completed online. The test asks basic questions not only about personal preferences but also about behavior.

Scoring is relatively straightforward; a number of books contain information about the MBTI along with simple scoring and assessment tools. However, for official MBTI results, the test should be taken through an official MBTI testing site — such as the Center for Applications of Personality Type — or through a certified MBTI administrator.

The accessibility of the MBTI does not necessarily make it the best assessment available. Experts such as John Lounsbury, a psychologist at the University of Tennessee Knoxville, have suggested that the MBTI is "overly simplistic and misses out on a few key traits, and that better tests exist" (Lok, 2012). While these criticisms may have some validity, the MBTI remains popular because it is easy to administer, easy to score, and easy to interpret.

The main criticism of the MBTI as a vocational assessment is that, unlike some other instruments, it does not measure abilities, character, or even personality traits in the traditional sense. Instead, it focuses on assessing personal strengths and weaknesses as determined by individual preferences. The test should not be used to eliminate candidates from certain jobs or to push people into particular career paths, though it can be useful in helping someone explore his or her own vocational direction. It is critical to recognize that the MBTI does not suggest that a person's preferences dictate ability — only that they dictate preferences. For example, introverts can perform well in group settings, but doing so will not be a natural preference for them.

Conclusion

Scott, D. G. (1999). Psychometric properties of the Myers-Briggs Type Indicator. Masters Coursework Thesis, Department of Psychology, University of Melbourne. Retrieved October 16, 2014, from Minerva website: https://minerva-access.unimelb.edu.au/handle/11343/36039