Many researchers, however, have long questioned the MBTI’s scientific merit.
“In social science, we use four standards: are the categories reliable, valid, independent, and comprehensive?” Adam Grant, a professor of industrial psychology at the University of Pennsylvania’s Wharton School, wrote in
an essay on the subject. “For the MBTI, the evidence says not very, no, no and not really.”
These faults are likely in part because neither of its creators, Katherine Cook Briggs and her daughter Isabel Briggs Myers, had formal training in psychology, explained Merve Emre, author of "
The Personality Brokers,” which explores the history of the MBTI.
Katherine Briggs became interested in Carl Jung’s book “Psychological Types” and began “typing” everyone she knew, said Emre, a professor at Oxford University. In 1943, amid the labor boom of World War II, her daughter took that system and designed a questionnaire to determine what job a worker’s personality is best suited for.
“It really was this very unscientific process,” Emre said.
Research has since found that upwards of 50% of people got a different score when they re-took the MBTI just five weeks later. Studies have also shown that the test is not effective at predicting people’s success in different jobs.