Social preference was measured by peer sociometric interviews from ages 5–9 (Keiley et al., 2003). Children nominated up to three classmates they especially liked and up to three they especially disliked. The frequencies of liking and disliking were summed for the target child and standardized within their classroom. Social preference was calculated by subtracting the child’s disliking score from his or her liking score, and scores were averaged within time frame. Social preference scores at age 9 were only available for cohort 1.
