Factors related to changes in IQ: a follow-up study of former slow learners

A group of 41 former slow learners were tested as children and at the age of 30 years. Information about family and personal problems met during childhood was available from the local school files and also by an interview at the age of 30 years. Changes in IQ were associated with the problem score and further education after leaving the compulsory school system. The group of subjects with the greater number of problems and further education improved their IQ scores by 18.1 points, against 5.0 points in the group with one or no problems and without further education.