All of the variables chosen for analysis were obtained from the FF4 interview (n=1900), with the exception of CD, ASPD and NS, which were assessed in the self-report questionnaire associated with the FF4 (n~1470); SE, which was assessed at the third wave interview (n=1887); and panic disorder, which was assessed at the second wave interview (n=1994). We had no measures of ADHD or SS in the FF twin pairs.
