A longitudinal study of dental students' personality type preferences.

The Myers-Briggs Type Indicator was administered to five classes of students at the beginning and end of their dental education. The 161 students who completed both tests were categorized according to personality type. The Spearman rank-order correlation of the two sets of data was calculated and tested. Changes in personality type between the tests were noted using two different standards. The first standard defined change as any alteration in the four-letter MBTI designation and thus was a measure of change in type. The second standard defined change utilizing the 95 percent confidence interval of the continuous score of each of the four MBTI scales and thus was a measure of change in the underlying construct, personality. The first standard indicated 75.8 percent of students change type; the second indicated 11.2 percent changed personality. These data are consistent with previously reported studies, but raise questions regarding what is being measured and how the data are being analyzed.