I am not aware of that kind of study. The book I am almost finished writing, a longitudinal study from the people in my first book, is full of social and emotional issues and barriers that make far too many people not fulfill on the promise their giftedness would seem to predict. I'm trying to get more people to understand how important it is to support parents and families to stop generational dysfunction and give all people a chance to blossom and live into their potential. What you did and shared is just perfect. Thank you for the work you have done and keep sharing it in your retirement. I'm retired, (sort of) too!