There is an additional test that they started taking a few years ago called the AIQ (Athletic Intelligence Quotient).
"The AIQ measures the intellectual abilities most used in attaining, enhancing, and applying athletic skills. Just as a stopwatch measures speed, the AIQ provides valuable information about an athlete’s performance-specific intellectual abilities. The AIQ identifies an athlete’s mental strengths and weaknesses, helps coaches train athletes to reach the highest level of performance, and aids management and player personnel in scouting and roster decisions. "
More about it here: http://athleticintel.com/aiq/
SI had an article about it this past week and their 'sources' say that Mayfield scored very high on this year's AIQ..
Good article and worth a read: https://www.si.com/nfl/2018/03/22/baker-mayfield-advance-analytics-nfl-draft-oklahoma-pff