Posted on October 23, 2020 by P.K. Maric
Many companies use personality tests in their hiring process. It makes sense when you think about it: It’s a scientific approach to find the right person for the job. Suppose you need to hire someone who works well in a team. In that case, a personality test that analyzes their psychological profile could help, right? The problem is…
The Most Widely Used Personality Tests Don’t Work
The most widely used personality test in hiring is the Myers-Briggs Type Indicator (MBTI). Unfortunately, the MBTI has been thoroughly analyzed by psychologists and confirmed to be bogus pseudoscience. Though people often find that their test result describes them very well, this is nothing more than the Barnum effect, which is a phenomenon in which a description of personality is supposedly tailored to a specific individual, but in reality it’s vague and general enough to apply to a wide range of people. Horoscopes rely on the same effect, but you wouldn’t hire someone based on their zodiac sign, would you?
Some versions of the Myers-Briggs test sort people into archetypes with fancy names like “Commander” or “Adventurer.” But the test is so unreliable that over 50% of people get a different result on repeated testing.
Another popular personality assessment used in hiring is DISC (Dominance, Influence, Steadiness, and Conscientiousness). However, DISC is an ipsative test, which means that it measures how people prefer to behave, not how they actually behave. Some sources claim that DISC has a validity of 91%, but this is just face validity, meaning that people taking the test agree that the test “looks like” it measures what it claims to measure. There is no evidence that DISC results accurately measure personality. Even DISCprofile.com says that DISC is “not recommended for pre-employment screening” as “DISC does not measure specific skills, aptitudes, or other factors critical for a position.”
Personality testing is complicated because personality itself is a complex psychological field. Tests that offer quick and easy-to-understand assessments are usually nonsense.
Accurate Personality Tests Are Still Problematic
Modern psychology has completely debunked the idea that people fall into certain types. Personality traits are more complicated than that. There are valid personality tests used in psychology, such as the Minnesota Multiphasic Personality Inventory (MMPI), or the Five-Factor Model (FFM) – also called the Big Five personality traits. Let’s take a look at the Big Five since it’s relatively easy to understand. It measures the five following personality traits:
- openness to experience (inventive/curious vs. consistent/cautious)
- conscientiousness (efficient/organized vs. extravagant/careless)
- extraversion (outgoing/energetic vs. solitary/reserved)
- agreeableness (friendly/compassionate vs. challenging/callous)
- neuroticism (sensitive/nervous vs. resilient/confident)
Notice that these traits are not the ones claimed by either MBTI or DISC and that these traits are not binary but a spectrum. This means you are not either nervous or confident on the neuroticism scale but fall somewhere in between, leaning more towards one side or the other, or perhaps even in the middle. So you can’t use this test to sort people into easily identifiable categories like with the MBTI or DISC.
While this personality test does have some degree of validity, should you use it in your hiring process? Well, no, because while it is accurate to an extent, it’s been criticized for being very limited and only accounting for about 56% of the normal personality trait sphere.
Should you use the MMPI instead? Good luck with that. The MMPI is considered a protected psychological instrument that can only be administered and interpreted by a trained psychologist. It’s also copyrighted property of the University of Minnesota, so you need to pay a fee to use it.
But let’s say you manage to find yourself a good personality test that suits your hiring needs and have an expert capable of administering it correctly. Well, it turns out that personality has almost no correlation with job performance. A study of various personnel selection methods has found that only conscientiousness shows any correlation with job performance, and the correlation is relatively low.
If you still want to use a personality test as part of your hiring process, you’ll encounter another problem: lying. People lie on personality tests all the time. Wouldn’t it be nice if there was a way to screen job candidates that makes lying impossible? Well, there is…
If personality tests are not necessary for hiring, then what should you do? Just avoid them and use better candidate screening techniques.
The better methods are ones that many companies are already using, in one way or another: knowledge and skill tests. Work-sample tests are an excellent way to predict job performance. The idea behind them is simple: to test if a candidate will be good at work, give them a sample of actual work to do. Evaluating a candidate’s ability in this way is by far the most accurate way to predict their job performance. Though to be effective, you need to know when and how to test a candidate’s knowledge and skills. A good skill test focuses on job-relevant knowledge. The tasks and questions should be appropriate for the skill-level you’re looking for, not too easy, or you risk hiring candidates who will be unsatisfied with the work and soon quit, and not too hard, or you miss out on hiring candidates who would have been skilled employees.
You can even do this remotely before you invite candidates to an interview, which can save you a lot of time.
Do you use personality tests in your hiring process? You shouldn’t. Not only are they utterly useless, but they’re counterproductive. Most widely used personality tests are scientifically invalid, so they offer no useful information. They might lead you to hire the wrong person or to miss out on good candidates. But even scientifically accurate personality tests aren’t helpful because it turns out that personality has almost no correlation with job performance.
Instead, you should test a candidate’s skills with tasks that are relevant to the job.