Table 1.

Consequences of involvement in bullying behaviour in childhood and adolescence on outcomes assessed up to 17 years of age

	Findings			Example references
Outcome	Victims	Bullies	Bully/victims
Health and mental health
Anti-social personality disorder	No significant association was found between victims and delinquent behaviour.	Bullying perpetration was strongly linked to delinquent behaviour.	Bullying victimisation was associated with delinquent behaviour.	26
Anxiety	Pre-school peer victimisation increases the risk of anxiety disorders in first grade. Peer victimisation (especially relational victimisation) was strongly related to adolescents’ social anxiety. Moreover, peer victimisation was both a predictor and a consequence of social anxiety over time. However, Storch and colleagues’ results showed that overt victimisation was not a significant predictor of social anxiety or phobia and relational victimisation only predicted symptoms of social phobia.	–	–	27–29
Borderline personality symptoms (BPD)	Victims showed an increased risk of developing BPD symptoms. Moreover, a dose–response effect was found: stronger associations were identified with increased frequency and severity of being bullied.	–	–	30
Depression and internalising problems	Monozygotic twins who had been bullied had more internalising symptoms compared with their co-twin who had not been bullied. Peer victimisation was associated with higher overall scores, as well as increased odds of scoring in the severe range for emotional and depression symptoms. Victims were also more likely to show persistent depression symptoms over a 2-year period. Moreover, a dose–response relationship was found showing that the stability of victimisation and experiencing both direct and indirect victimisation conferred a higher risk for depression problems and depressive symptom persistence. A meta-analytic study showed significant associations between peer victimisation and subsequent changes in internalising problems, as well as significant associations between internalising problems and subsequent changes in peer victimisation.	Being a bully was not a predictor of subsequent depression among girls but was among boys.	Bully/victims exhibited significantly greater internalising problems.	31–36
Psychotic experiences	Being bullied increased the risk of psychotic experiences. Also a dose–response relationship was found where stronger associations were identified with increased frequency, severity and duration of being bullied.	–	–	37 38
Somatic problems	Children and adolescents who are bullied have a higher risk for psychosomatic problems such as headache, stomach ache, backache, sleeping difficulties, tiredness and dizziness. They were also more likely to display sleep problems such as nightmares and night-terrors.	Pure bullies had the least physical or psychosomatic health problems.	Bully/victims displayed the highest levels of physical or psychosomatic health problems.	39–42
Self-harm and suicidality	Those who are bullied were at increased risk for self-harming, suicidal ideation and/or behaviours in adolescence. Moreover, a dose–response relationship was found showing that those who were chronically bullied had a higher risk of suicidal ideation and/or behaviours in adolescence. Lastly, cyberbullying victimisation was not associated with suicidal ideation.	Pure bullies had increased risk of suicidal ideation and suicidal/self-harm behaviour according to child reports of bullying involvement.	Bully/victims were at increased risk for suicidal ideation and suicidal/self-harm behaviour.	26 43–46
Academic achievement
Academic achievement, absenteeism and school adjustment	A significant association was found between peer victimisation, poorer academic functioning and absenteeism only in fifth grade. Frequent victimisation by peers was associated with poor academic functioning (as indicated by grade point averages and achievement test scores) on both a concurrent and a predictive level. Pure victims also showed poor school adjustment and reported a more negative perceived school climate compared to bullies and uninvolved youth.	Pure bullies showed poor school adjustment.	Bully/victims showed poor school adjustment and reported a more negative perceived school climate compared to bullies and uninvolved youth.	47–49
Social relationships
Dating	–	Direct bullying, in sixth grade, predicted the onset of physical dating violence perpetration by eighth grade.	–	50