Judy Mack’s research while affiliated with University of Minnesota, Duluth and other places

Used the Minnesota Scholastic Aptitude Test to study 22,538 female and 22,770 male high school students representing almost all high school juniors in Minnesota. Results indicate a relationship between birth order and verbal intelligence. The proportion of planned college attendees decreased, and the proportion of students interested in technical training outside of college increased, as the birth order progressed from first- to last born. (PsycINFO Database Record (c) 2012 APA, all rights reserved)