Emotional and behavioral functioning within the TCHAD study were also assessed via parent report, using the Child Behavior Checklist when the twins were 8–9 years old. The CBCL includes 118 items that describe the child’s behavioral, emotional and social problems, and 8 subscales: withdrawn, somatic complaints anxious/depressed, social problems, thought problems, attention problems, delinquent behavior and aggressive behavior. All 8 subscales were included in a stepwise regression analyses in the TCHAD sample.
