Should personality assessments be used in hiring?

Read time 5 min read

Lately, a common hiring practice has come under scrutiny: personality testing in the interview process. 

The Myers-Briggs Company has long held the position that the Myers-Briggs Type Indicator^® (MBTI^®) instrument shouldn’t be used in hiring, but rather for team building, conflict management, leadership development, and other non-selective purposes. 

Does this mean we should stop using all personality assessments in hiring? 

In short, no. Personality assessments can play a helpful, objective role in the hiring process, provided that:

1. The proper assessment is used.
2. Insights are applied correctly.
3. It’s not the only way you’re determining who to hire.

When used correctly, personality assessments in hiring can reduce discrimination based on gender, ethnicity, and other factors. 

For instance, while cognitive ability tests have produced an adverse impact on certain demographic groups, personality assessments generally don’t discriminate against members of protected groups. Furthermore, they can help employers identify candidates who are likely to perform well—and stick around.

Can personality predict job success?

Personality is made up of psychological preferences, temperaments, and predispositions. And while many factors influence us (including social and cultural pressures), personality is a major force behind our habits, behaviors, and attitudes. So, it’s not surprising that some personality assessments can be a strong predictor of job performance. 

Think about two common work roles: sales and accounting. 

Most people would intuitively guess the different industries are filled by people with very different personality characteristics. In my experience—and others’—this is certainly the case. 

Why do salespersons and accountants tend to differ? Think about their duties, which require specific behaviors. Because personality is a major factor in preferences and behavior, it influences job performance by determining whether an individual has a natural affinity for required job duties. And employees are most effective when their personalities and interests align with job requirements. 

Imagine two candidates with equal cognitive ability, education, and experience, and how they might differ along the scales identified by the California Psychological Inventory^™ (CPI^®) assessment. One who scores lower on the ‘flexibility’ scale may be less comfortable performing the sales position duties. On the other hand, this lower flexibility score may be beneficial for accounting, which involves a high degree of structure and discipline and less ambiguity in decision-making.

In short, we tend to do better when our work supports how we’re naturally inclined to think and act, and assessments that predict this alignment can be very helpful in candidate selection. 

Hire for engagement and longevity

Hiring is about more than just raw ability or previous accomplishments. You consider whether someone is likely to stick around for the long-term and how engaged they’ll be while they’re at your company. These outcomes are mostly determined by one simple factor: how much people enjoy their job. And being satisfied in your career is also influenced by personality.

People find the ability to express their personality intrinsically rewarding, and therefore enjoy work environments that allow them to be themselves. There’s a direct link between workplace engagement and profit, as well as a correlation between engagement and performance. 

Back to my earlier example, those who show lower levels of flexibility may be able to work in sales but might not find it as rewarding or enjoyable. Consequently, they’re more likely to leave in favor of a position more aligned with their personality. Assessments can help identify the right individual for a work environment. 

Not all personality assessments are suited for personnel selection 

Organizations should proceed with the utmost care when using personality assessments for hiring. If the assessment isn’t psychometrically validated for hiring and selection, you can make poor decisions or find yourself in legal trouble. In many cases, using a personality assessment for hiring when it wasn’t designed to be used for hiring is unethical (which is why using the MBTI assessment for hiring is unethical). 

When we talk about the suitability of an assessment, you must first consider its reliability and validity. Reliability means that if the same person takes the same test multiple times under similar circumstances, they’re likely to get similar results. Validity, on the other hand, refers to its ability to measure what it purports to measure. 

Many assessments on the market can’t be shown to have either sufficient reliability or validity. Such tools shouldn’t be used in any professional setting, much less for hiring. If you can’t get your hands on documentation showing that the assessment has acceptable reliability and validity data, don’t use it. 

But you also have to consider if the assessment has been sufficiently validated specifically for hiring and selection use cases. Here’s where I think some human resources departments get a little tripped up: an assessment can be psychometrically validated for one use case but be highly inappropriate for another use case. 

The MBTI instrument, for instance, has been psychometrically validated for its intended use—but not for hiring and selection. The assessment tells you many things and can help you identify existing employees’ strengths and development areas, but it wasn’t designed to predict job performance. 

Other tools, however, have been designed and validated to predict job performance. If you’re looking to use personality assessments in hiring, keep these points in mind:

• Generally, personality assessments that measure traits are appropriate for selection purposes (measures of psychological type aren’t designed for selection). 
• An assessment is considered reliable if scores remain consistent over time—the general standard for a psychometric assessment is an internal consistency reliability of .70 or above.
• A valid assessment measures what it purports to measure. If a test is used to select individuals for employment, there must be extensive documentation of its ability to predict job performance.

Lastly, use personality assessment in conjunction with other tools.

I’ll close by stressing that personality assessments—regardless of the science behind them—shouldn’t be used as the sole determinant in hiring decisions. But when they’re one part of a well-rounded hiring process that includes interviews, references, and more, they provide valuable insight that can end in a great hire.

This article was written by Sherrie Haynie, Sr. Director of US Professional Services at The Myers-Briggs Company, and first published by Forbes Coaches Council, June 2021.