12.88). To investigate potential gender differences in change scores, independent
t-tests were conducted, revealing a significant difference between
girls (M = −0.47, SD = 5.29, n = 266) and boys (M = 0.87, SD = 8.93,
n = 307) on peer-nominated bullying behavior, t(508.14) = –2.21, p = .027.
None of the other change scores showed significant gender differences.