Tables 2, 3, 4 and 5 provide an overview of the sample sizes and mean levels of aggression and all other traits. We replicated the well-established gender differences in average aggression scores at most ages for parental ratings. The gender difference was smaller or close to absent for self-reports. For example, while the difference between boys and girls is in general about 1.5–2 points on the CBCL and SDQ parental reports, the differences based on self-report ranged between 0.05 and 0.67.