Exposure to frequent bullying by peers before age 12 was associated with an increased risk of self harm at 12 years of age, whether bullying was reported by mothers (relative risk 3.53, 95% confidence interval 2.10 to 5.93) or by children themselves (3.33, 1.91 to 5.82). This association was equally evident among both boys and girls, for both reporting sources (figure). Therefore, the remaining analysis included both sexes together.
