This Insights was contributed by Rebekah Cardenas, Ph.D., vice president of business development and assessment solutions at EASI·Consult®. 
 
Clients often ask what I think about widely used personality tools, like the Myers-Briggs Type Indicator (MBTI) or DISC Personality Test. My response almost always begins with a question – “For what purpose?”  What I think about a particular tool depends in part on how you intend to use it. There are many in-depth articles that dig into the history, credibility and rigor of specific tools, such as this one on the MBTI or this one on the DISC. Instead of covering something that’s already been said, let’s examine basic legal requirements regarding hiring so that you can decide if your favorite tools measure up.
 
As you probably know, the United States has a number of strongly enforced anti-discrimination laws that limit the way organizations can use testing programs and tools for making Human Resources decisions. Major laws include the 1964 and 1991 Civil Rights Acts, the Americans with Disabilities Act (ADA) and the Age Discrimination in Employment Act (ADEA). While it’s nearly impossible to memorize everything these laws require, there are some general rules that span them that you should remember:
 

1. Ensure that the test measures the important requirements of the job being filled. Employers have an obligation to prove that the tools used for hiring decisions are job relevant, and that means anything asked of the employee must relate directly back to the specific requirements of the job. Knowing what type of person someone is (an intuitive and feeling, for example) does not tell you anything about whether or not he or she will be successful in a particular role. The problem:  lack of job relevance.
    
2. Ensure that the test produces consistent results over time. If you retake a test and your personality profile or type changes, you should question the reliability of the tool. Yet, many popular tools produce results that change over time and yet still are relied upon to make important employment decisions. The problem: lack of consistency.
    
3. Verify the validity of the test for your specific application. A particular test may measure what it is supposed to measure – psychologists call this content validity. But that doesn’t mean it will predict success on the job, which we call predictive validity. The ability to predict job performance is essential for tools used in hiring decisions. So if you want to use a tool for team building, look at results others have found for that purpose and in that context. However, if you want to use a tool as the basis for any type of employment decision — from hiring to promoting to compensating — be sure you find evidence that the tool can actually predict job success. You may be surprised at how hard it is to find this type of evidence. The problem: lack of prediction.