Why Myers-Briggs is Not an Effective Screening Tool
In the HR world, Myers-Briggs (MBTI) is a well known name. According to the test, there are 16 different personality types across four dichotomies. Many are familiar with whether or not they are an INTJ, ESFP, and so on.
Millions of students and adults take the test each year as part of career screenings and self-assessments. For decades, this personality assessment has assessed the strengths, weaknesses, likes and dislikes, for multitudes of test takers - resulting in career choices, team workshops and employers determining whether or not candidates are hired.
However, on their own website, Myers-Briggs has stated:
“It is unethical and in many cases illegal to require job applicants to take the Indicator [MBTI] if the results will be used to screen out applicants.”
There are a number of reasons why Myers-Briggs falls short as a screening tool for jobs:
It Lacks Performance Prediction
This is the biggest problem with using the MBTI as a selection tool.
Myers-Briggs can be an effective primer to have discussions about personal styles and preferences. But, there is no evidence to suggest that personality types as measured by the MBTI predict job performance. You need to be able to demonstrate that your selection tool predicts job performance for a number of reasons. Not only do you want your investment to be worth your time and money, but you also need to ensure that you are on solid legal ground with your use of assessments. You could get into some serious trouble if you hire people based on factors that don't predict job performance.
When choosing a personality assessment, you are safer to use one that leverages the Big 5 model of personality. Personality tests that use this model have demonstrated relationships with job performance. They also measure conscientiousness, i.e. someone who would be considered a "go-getter" because they would work hard to get the job done. Conscientiousness is a trait that manifests itself in talents like execution and innovation, and is important for almost all roles, regardless of industry.
A test that also captures cognitive characteristics (e.g., reasoning, learning) is advised as well. This will give you a more well-rounded view of your candidate. For example, an employer may hire an outgoing salesperson, but without the ability to handle complex situations, this salesperson’s performance may show that she is able to talk, but not able to understand the client and develop a strategy to sell. Cognitive ability also has a mountain of evidence to demonstrate its relationship to job performance.
It Creates Artificial Dichotomies
There is a vast difference between a person who just barely prioritized extraversion over introversion, and someone who is highly extraverted. Someone who is at the highest level of extraversion will adore the spotlight, have the ability to handle public speaking with ease, and revel in large crowds.
For many of those in the middle of the extraversion spectrum, the above could sound like a nightmare. However, in the Myers-Briggs assessment, if you are considered 51% extraverted, you are put in the same category as someone who is 100% extraverted.
“The MBTI reminds us of the obvious truth that all people are not alike, but then claims that every person can be fit neatly into one of 16 boxes,” Indiana University’s David J. Pittenger said in an article. “I believe that MBTI attempts to force the complexities of human personality into an artificial and limiting classification scheme.”
I agree with Pittenger’s opinion. The alternative is to assess people along a continuum of personality. For example, a continuum of introversion and extraversion. This allows for us to account for a complex array of personality combinations. And let’s be real - personality is complex. Shouldn’t we be accounting for that?
It Lacks Job Relatedness
Often when the MBTI is used to screen job candidates, the hiring team will arbitrarily prioritize traits based on intuition. Going back to our salesperson example, the hiring team may believe that a salesperson needs to be extraverted, and exclude a candidate who does not receive an ‘E’ from the MBTI assessment. Yet, our own research has found that extraversion is not always important for sales roles.
Demonstrating the job-relatedness of a trait measured in an assessment is crucial to properly using the tool and ensuring its defensibility. A tried and true method for demonstrating job-relatedness is conducting a job analysis to link traits measured by the assessment to behaviors required for the job.
Because the MBTI is not designed for hiring, there is no built-in job analysis to link traits measured by the MBTI with requirements for a specific job. This means that you could be screening candidates using traits that have nothing to do with job success, and losing out on the best candidates.
What I appreciate about the MBTI is that it has people talking about their personality and how it affects behavior and team dynamics. But, even by their own admission, it should never be used as a selection tool.
Plum, on the other hand, assesses a combination of cognitive ability and Big 5 personality traits, offering a scalable way to assess characteristics that are highly predictive of job performance. That’s because 50+ years of Industrial/Organizational Psychology - or, the study of psychology in the workplace - is at the core of what we do.
The science makes it clear - MBTI has been widely recognized as lacking evidence for predictive validity. The goal of any pre-employment assessment should be to measure as many job-related characteristics (such as Big 5 personality traits and cognitive ability) as possible. Not only does an assessment with this objective give you a well-rounded picture of the candidate before they enter the job, but it also leads to the highest possible relationship between assessment scores and job performance - and therefore, high predictive validity.
Leann Schneider is the Product Manager at Plum, where she applies her passion for research-based practice, practical insight, and coaching-supported development to Plum's product development and client delivery. She obtained her PhD in Industrial/Organizational Psychology at the University of Guelph, and she has research published in several peer-reviewed journals.