Brendgen et al

-pps recruited from Quebec Newborn Twin Study, 322 pairs at start but complete data gathered on 234 pairs 

-data gathered longitudinally at different months and then at 6 yrs 

-data was 2 ratings of each twins behaviour, by teacher and classmates

-scores given by teachers was done on 3 point scale, peer ratings done by giving each child booklet containing photos of each child in class - circled 3 photos that…