Even though personality tests like Myers-Briggs have been widely discredited -- Adam Grant says if you put a horoscope on one end and a heart monitor on the other, the MBTI falls about halfway in between in terms of accuracy -- plenty of people swear by personality testing to identify candidate fit. 

But there's a bigger problem than whether the results of a particular personality test are valid. According to the results of a 2019 study published in Journal of Applied Psychology, applicants tend to shape their responses in order to increase their person to organization fit.

(Job candidates) infer the personality profile of a presumably ideal candidate from information about organizational culture and then fake accordingly on a personality inventory.

Results of our studies show that this type of faking is highly specific because applicants fake only on targeted traits, in a specific manner.

For example, in competitive cultures they portray themselves as being less honest and agreeable, whereas in innovative cultures they portray themselves as more open and extraverted, thus displaying precisely the personality profile that is closely aligned with higher levels of competitiveness or innovativeness. (My italics.)  

All of which comes as no surprise to anyone who has taken a personality test for any reason other than to learn more about themselves. If I know you value quality over productivity, I'll make sure to answer prompts about attention to detail or meeting expectations the right way. If I know you value teamwork, I'll make sure my answers stress "we," not "me."

All of which might sound shady or unethical.

But not necessarily. 

As the researchers write, "This research highlights the adaptive component of faking and underlines that it should not be considered a behavior that only dishonest individuals show."

Granted, you might be thinking, "I would never tailor my responses to match what the company appears to value." Or, "I don't need to tailor my responses; I applied for the job because I know the company's values align with mine."

Still: the goal of applying is to get hired. That's why many job seekers don't send  boilerplate resumes; they tailor each resume to the specific position and company. That's why many job seekers tap into their networks before an interview; they want a sense of how to best highlight their qualifications and experience. As the researchers write, "applicants will adapt their motivation and their behavior based on information obtained at different stages of selection." 

Again, the goal is to get hired -- which means showing (or at least presenting) yourself to be the best candidate.

So the next time you consider using a personality test to determine a candidate's cultural fit, take a second to reconsider.

Maybe you'll do what Relevant Sports Group CEO Daniel Sillman does and check references before you conduct interviews. As Daniel says, "That helps me better understand who the person is, their background, their experiences not just as a professional but also as a human: What drives them, what motivates them... and whether they share the core values that fit our company's culture."

Or maybe you'll ask some of the most common behavioral interview questions to identify how the candidate works -- and what they have actually done, not what they say they would do.

But whatever you do, think hard about whether the personality test you administer tells you anything more than whether a candidate is able to read your culture's tea leaves... and adjust his or her answers accordingly.