Most large organization use personality testing in one form or another. This can be to select the best candidates or to help in improving performance of individuals and teams. Examples include the Myers-Briggs personality inventory and the Five Factor Model. How useful are these assessments really?
Personality assessments have long proven to be better predictors of workplace performance over job-related ability tests. In this article we’ll discuss a few well known tests and look at their validity and application.
The validity of the Myers-Briggs Type Indicator
The Myers-Briggs Type Indicator (MBTI) remains one of the most popular personality tests for businesses because of how intuitively it categorizes behavior categories, with researchers having identified the five types most likely to achieve high salaries, positions of responsibility or to run their own business. A nice overview is compiled by Sage in this infographic.
The MBTI assumes that every personality is made up of a combination of four dichotomous categories. By combining these categories, a person discovers his or her preferred styles of thinking and working.
The test is easy to understand, quick to complete and can be self-administered.
Unfortunately, despite its persistent popularity, evidence supporting the reliability of MBTI is lacking. Its test-retest score (i.e. the likelihood of a person taking the same test five weeks later and receiving the same outcome) is low, ranging from 0.42 to 0.78, where 0.8 is considered the minimum acceptable score. Furthermore, the theory that personality traits are dichotomous, as opposed to continuous, has been challenged by psychologists since the theory’s conception.
Fortunately, there are alternatives to the MBTI. For instance, rather than categorizing a person into one of two dichotomous categories—like deciding if someone is an extravert or an introvert—the Predictive Index (PI) measures a person’s level of extraversion – i.e. someone may be 43 percent extraverted.
The PI, which has been widely used in the past five decades, was developed especially for “occupational and organizational populations”, primarily measuring levels of dominance, patience and formality; traits considered desirable within business.
However, too many of one type of personality can be detrimental; a team of dominant and extraverted characters will make fast decisions right up until they disagree, wherein there will be heated arguments and a halt to productivity.
Another model, the Adaptiv Resilience Factor Inventory which has also been widely used focuses more on understanding a person’s levels of empathy and resiliency. This test could potentially help scale how well a person might work well with diverse personalities to provide a balance to teams. Unfortunately, there has so far been little independent research conducted to support the validity of this test.
The Big Five
To date, the most empirically verified theory that businesses can use to predict employee performance is the Five Factor Model (FFM) aka the “Big Five personality traits”.
Rather than starting out as a way of determining personality, the FFM evolved over many years as numerous psychologists identified shared personality traits amongst people of different cultures and backgrounds. These traits which are stable and (partially) innate are divided into the following categories:
- Need for Stability
For instance, originality refers to a person’s toleration for the unfamiliar, with high scorers tending to show creativity and curiosity, while low scorers are often unartistic and conventional.
Crucially, scores are scaled, rather than determining someone is one label or another. It also refuses to combine the results of the five categories into defined types, unlike the MBTI. The FFM recognizes that personalities change over time and according to different stimuli, so only seeks to offer a general description of a person’s most common tendencies.
That’s not to say the FFM is entirely reliable, with some critics suggesting its categories are too broad or lack the ability to measure certain traits (like a person’s realism).
If personality tests are vague, is it better to discard them altogether?
A functioning business requires a balance of personality types to succeed. Outgoing and creative employees are excellent for morale and coming up with ideas to move a business in new and innovative directions, but without more focused individuals to keep them grounded, these ideas may never be realized.
Thus, while assessment improvement is still needed, it remains important to get a sense of potential hires and how they might work with others. Naturally, there are alternative means to traditional tests for predicting a candidate’s aptitude, such as interviews, problem-solving and teamwork activities which are being increasingly used alongside personality assessment to provide insight.
In fact, modern personality assessment is showing signs of adapting to include more engaging means of measurement, such as games or simulated scenarios, to examine how people respond to various work-related situations while avoiding the bias of self-reporting. Contemporary research suggests that “play style” correlates with personality as a form of behavioral assessment – although the verdict is still out on the effectiveness of these kinds of tests. Effectiveness is best determined on a case by case business – and as a tip: don’t believe everything the test vendor says!
While new theories and testing methods are constantly being developed, the FFM remains the most reliable and well-validated means for businesses to predict worker behavior.