Do you agree with the results? What evidence is there in the literature to support or disconfirm your personality profile?

J Best Pract Health Prof Divers (Spring, 2017), 10(1), 1–27. ISSN: 2745-2843 © Winston-Salem State University

ORIGINAL RESEARCH

Validity and Reliability of the Myers-Briggs Personality Type Indicator: A Systematic Review and Meta-analysis

Ken Randall,1 PhD, MHR, PT; Mary Isaacson,1 EdD; Carrie Ciro,1 PhD, OTR/L, FAOTA

Author Affiliations: 1Department of Rehabilitation Sciences, University of Oklahoma Health Sciences Center, Tulsa and Oklahoma City, Oklahoma

Corresponding Author: Ken Randall, Department of Rehabilitation Sciences, University of Oklahoma Schusterman Center, 4502 East 41st Street, Room 2H20, Tulsa, OK 74135 (Ken-Randall@ouhsc.edu)

ABSTRACT

The Myers-Briggs Type Indicator is frequently used by health professions and educational programs to address the diversity of personalities that exist. No systematic review of the litera- ture or meta-analysis of its validity and reliability has occurred. This comprehensive literature search identified 221 potential studies, of which seven met our inclusion criteria. Four of the studies examined construct validity, but their varying methods did not permit pooling for meta-analysis. These studies agree that the instrument has reasonable construct validity. The three studies of test-retest reliability did allow a meta-analysis to be performed, albeit with cau- tion due to substantial heterogeneity. Results indicate that the Extravert-Introvert, Sensing- Intuition, and Judging-Perceiving Subscales have satisfactory reliabilities of .75 or higher and that the Thinking-Feeling subscale has a reliability of .61. The majority of studies were con- ducted on college-age students; thus, the evidence to support the tool’s utility applies more to this group, and careful thought should be given when applying it to other individuals.

Keywords n Myers-Briggs Type Indicator n Personality n Reliability n Validity

2 J Best Pract Health Prof Divers: Vol. 10, No. 1, Spring 2017

INTRODUCTION

Personality is a commonly used term with a meaning that most of us readily comprehend, and yet it is an elusive concept to fully describe or quantify. Broadly defined, it is the combination of an individual’s cognitive, emotional, attitudinal, and behavioral response patterns (Angler, 2009; McAdams, 2009). It has been studied since antiquity, with Hippocrates being among the first to describe personality by grouping individuals into temperaments that related to particular characteristics or types (Hippocrates 1923). Since then, countless theories and instruments have attempted to explicate and measure differences in personality more fully. Included in these instruments is the Myers-Briggs Type Indicator (MBTI), which is reported to be one of the most widely used instruments in the world for understanding personality differences (Briggs Myers, 1998; Jackson, Parker, & Dipboye, 1996; Lorr, 1991; Saggino & Kline, 1996; Salter, Evans, & Forney, 2006; Tzeng, Outcalt, Boyer, Ware, & Landis, 1984; Zumbo & Taylor, 1993).

The MBTI is used extensively in human resource management and is one of the most commonly used instruments in higher education research and counseling (Hojat, Erdmann, & Gonnella, 2013). Its application in medical education is quite varied and includes studies of how certain preferences affect decision making (Pretz & Folse, 2011) and how knowledge of an individual’s type can enhance communication (Eksteen & Basson, 2015). Moreover, addressing the differences in type and preferences between instructors and students may mini- mize negative outcomes in both academic and clinical settings (Bell et al., 2011). In the au- thors’ experience, we use the MBTI as both an educational and an academic advisement tool. Our occupational therapy and physical therapy students learn about the 16 MBTI types and about how differing preferences can influence interactions with members of the health care team and with patients and their loved ones. We also provide academic advisors and clinical instructors with information about individual student types that includes tips grounded in the MBTI literature on how to enhance their learning, communication, and feedback based on each student’s preference. Although we pay attention to the preferences of all students, we also examine the preferences of learners from diverse backgrounds to determine if any trends exist in personality type. In an ongoing effort to use the best evidence to inform our educational program, we wanted to understand the psychometric properties of the MBTI to determine whether we should continue to use it with our students.

Since its inception in the 1940s, numerous studies have examined various aspects of the MBTI, including many related to validity and reliability. Over the past 35 years, a number of relatively thorough reviews of the literature regarding these features of the MBTI have ap- peared (Carlson, 1985; Carlyn, 1977; Gardner & Martinko, 1996; Murray, 1990; Pittenger, 1993), including a compendium of research by the publishers of the tool itself (Thorne & Gough, 1999). However, none of these reviews was systematic in nature, nor did any apply

Myers-Briggs Personality Type Indicator 3

the guidelines of the Cochrane Collaboration (2016), considered the standard for compre- hensive literature searches (Sampson et al., 2006) and quality appraisal. In 2002, Capraro and Capraro conducted a meta-analytic reliability generalization study of articles investigating a number of the psychometric properties of the MBTI; however, the scope of the study was limited to articles published between 1998 and 2001. To date, we could find no completed systematic review of the literature or in-depth meta-analysis of studies that meet the standards suggested by the Cochrane Collaboration to assess the psychometric properties of the MBTI.

THE MYERS BRIGGS TYPE INDICATOR

The MBTI measures the degree to which an individual prefers to operate from four dichoto- mous type pairs using a series of forced-choice questions that represent behavioral prefer- ences. In accord with Jung’s theory of types, it proposes that everyone has a natural preference for one of the two opposites on each of four scales, emphasizing that one preference is not better than another. According to supporters of the MBTI, this distinguishes it from most psychological assessments, which quantify personality traits, many of which consider one end of the scale to be more positive and the other more negative (Schaubhut, Herk, & Thompson, 2009, p. 4). The MBTI emphasizes the word preference and uses single letters of the alphabet to denote its eight preferences. The definitions for each MBTI preference show a distinct link with Jung’s original definitions:

Extraversion (E) is the tendency to focus on the outer world of people and external events. People who prefer extraversion direct their energy and at- tention outward and receive energy from external events, experiences, and interactions.

Introversion (I) is the preference to focus on the inner world of ideas and ex- periences. Individuals direct their energy and attention inward and receive energy from their internal thoughts, feelings, reflections, and time alone.

Sensing (S) is the preference to take information in through the eyes, ears, and other senses. People who are predominantly sensing are observant of what is going on around them and are especially good at recognizing the practical realities of a situation.

Intuition (N) is the ability to take in information by seeing the big picture, focusing on relationships and connections between facts. People who prefer intuition tend to grasp patterns and are especially adept at seeing new pos- sibilities and different perspectives.

4 J Best Pract Health Prof Divers: Vol. 10, No. 1, Spring 2017

Thinking (T) is the preference in decision making to look at the logical con- sequences of a choice or action. People who prefer this type try to mentally remove themselves from a situation to examine it objectively and analyze cause and effect.

Feeling (F) is the use of emotion in decision making, and people with this preference tend to consider what is important to them and to other people. They mentally place themselves in a situation and identify with the people involved so that they can make decisions based on person-centered values.

Judging (J) is the preference to organize life in a planned, orderly way, with a desire to regulate and control it. People who prefer judging make deci- sions, achieve closure, and appreciate an environment that is structured and organized.

Perceiving (P) is the tendency to live in a flexible, spontaneous way, seeking to experience and understand life rather than control it. People who are perceiving prefer to be open to experience and last-minute options. They enjoy and trust their resourcefulness and ability to adapt to the demands of a situation (Briggs-Myers, 1993; Hall & Nordby, 1973).

The MBTI treats each preference equally, so there are no principal functions or sub- ordinate functions as described by Jung. Given four sets of dichotomous preferences that can occur in any combination, the MBTI proposes that there are sixteen different personality types. With the MBTI, four letters represent each type, which indicate the four dominant preference areas. For example, ENFP is Extraversion Intuitive Feeling Perceiving, which has its own set of characteristics, some like and some different from the other fifteen types. Simi- lar to Jung’s work in Psychological Types (1923), the MBTI addresses various combinations of each type, such as introverted-sensing or intuitive-thinking-perceiving. The MBTI allows its user to describe two people with the exact four-letter combination of preferences in generali- ties similar to both, yet accounts for the individual differences produced by variation of the extent (or strength) of each person’s preference. This echoes Jung’s belief that his types can be used to describe groups of people as well as individuals (Jung, 1921/1923).

According to the companion manual to the MBTI, Introduction to Type (Briggs Myers, 1998; Myers, Kirby, & Briggs Meyers, 2015), which was first published in 1970 and is currently in its seventh edition, the goal of the instrument is to foster self-understanding, enhance learning and communication, assist with conflict management, and enhance relationships. It is a tool “with intent not to stereotype, but to allow understanding of individual preferences” (Jessup, 2002, p. 503). Between 1943 and 1975, the MBTI evolved through a number of itera- tions, spanning Forms A through F. In 1975 Consulting Psychologist Press acquired the rights

Myers-Briggs Personality Type Indicator 5

to sell the MBTI as a proprietary instrument (Pittenger, 1993), and it became readily available for widespread use as Form G (McCaulley, 1990). In 1998, Form G underwent revision and was published as Form M, which can be administered by the publisher, by computer, or by using a self-scorable version. Additionally, two MBTI instruments that explore type more deeply are the Step II (first published as Form K in 1989 and subsequently revised as Form Q in 2001) and Step III (published in 2009). Step II explores differences within the same type, and Step III is administered only by counselors specifically trained in the tool in one-on-one sessions (Myers, McCaulley, Quenk, & Mitchell, 2009). There are currently four distinct forms of the MBTI, each differing in its use and scoring: Form M and Form M self-scorable, Step II Form Q, and Step III. The MBTI has a European version and has been translated into 21 languages, including Chinese, German, Italian, Japanese, Norwegian, and Spanish (Myers & Briggs Foundation, 2016).

Most criticisms of the MBTI relate to the dichotomous nature of the instrument, its translation of continuous scale scores into nominal categories of preference, and whether it reflects the theory on which it is based (Barbuto, 1997; Daisly, 2011; Pittenger, 1993; Zemke, 1992). The forced-choice nature of the MBTI does not allow respondents to select a median or neutral response (Barbuto, 1997); they must choose a response that places them into one preference or the other (either Extraversion or Introversion, Sensing or iNtuition, Thinking or Feeling, Judging or Perceiving). Scoring for the MBTI reflects the most frequently selected side of the four dichotomies, which determines preference, reflected in the four-letter com- bination that expresses overall type. Barbuto (1997) suggests that this nominal aspect of the MBTI results deviates from Jung’s original theory. These observations lead to questions regarding the validity and reliability of the MBTI (Zemke, 1992).