title: Does bullying cause emotional problems? A prospective study of young teenagers.
abstract: OBJECTIVE
  To establish the relation between recurrent peer victimisation and onset of self reported symptoms of anxiety or depression in the early teen years.
  
  
  METHODS
  Cohort study over two years.
  
  
  METHODS
  Secondary schools in Victoria, Australia.
  
  
  METHODS
  2680 students surveyed twice in year 8 (aged 13 years) and once in year 9.
  
  
  METHODS
  Self reported symptoms of anxiety or depression were assessed by using the computerised version of the revised clinical interview schedule. Incident cases were students scoring >/=12 in year 9 but not previously. Prior victimisation was defined as having been bullied at either or both survey times in year 8.
  
  
  RESULTS
  Prevalence of victimisation at the second survey point in year 8 was 51% (95% confidence interval 49% to 54%), and prevalence of self reported symptoms of anxiety or depression was 18% (16% to 20%). The incidence of self reported symptoms of anxiety or depression in year 9 (7%) was significantly associated with victimisation reported either once (odds ratio 1.94, 1.1 to 3.3) or twice (2.30, 1.2 to 4.3) in year 8. After adjustment for availability of social relations and for sociodemographic factors, recurrent victimisation remained predictive of self reported symptoms of anxiety or depression for girls (2.60, 1.2 to 5.5) but not for boys (1.36, 0.6 to 3.0). Newly reported victimisation in year 9 was not significantly associated with prior self report of symptoms of anxiety or depression (1.48, 0.4 to 6.0).
  
  
  CONCLUSIONS
  A history of victimisation and poor social relationships predicts the onset of emotional problems in adolescents. Previous recurrent emotional problems are not significantly related to future victimisation. These findings have implications for how seriously the occurrence of victimisation is treated and for the focus of interventions aimed at addressing mental health issues in adolescents.
authors.affiliation: Centre for Adolescent Health, Royal Children's Hospital, Parkville 3052, Victoria, Australia. bond@cryptic.rch.unimelb.edu.au
authors.forename: L
authors.initials: L
authors.lastname: Bond
authors.forename: J B
authors.initials: JB
authors.lastname: Carlin
authors.forename: L
authors.initials: L
authors.lastname: Thomas
authors.forename: K
authors.initials: K
authors.lastname: Rubin
authors.forename: G
authors.initials: G
authors.lastname: Patton
mesh_terms: D000293:Adolescent; D001008:Anxiety Disorders / Q000453:epidemiology / Q000209:etiology*; D019548:Crime Victims / Q000523:psychology* / Q000706:statistics & numerical data; D003866:Depressive Disorder / Q000453:epidemiology / Q000209:etiology*; D005191:Family Characteristics; D005260:Female; D006801:Humans; D015994:Incidence; D007398:Interpersonal Relations; D008297:Male; D011446:Prospective Studies; D011569:Psychiatric Status Rating Scales; D012008:Recurrence; D012737:Sex Factors; D014739:Victoria / Q000453:epidemiology