title: Time trends in child and adolescent mental disorders.
abstract: OBJECTIVE
  1995 saw the publication of a major review of time trends in psychosocial disorders of youth across the second half of the twentieth century. It found evidence for substantial increases in rates of youth crime, alcohol and drug use, depression and suicide in most industrialized countries in the decades following the Second World War, slowing in some instances in the 1980s. Ten years on, we review findings on more recent trends in rates of these and other indicators of child and adolescent mental health.
  
  
  RESULTS
  Prevalence estimates for autism spectrum disorders have increased in recent decades, as has public and professional awareness of hyperactivity and attention deficits. Trends in adolescent conduct problems, and in alcohol and drug use, appear to reflect culture-specific influences. Rates of suicide among young males, and self-harm among females have risen in many countries in recent years; trends in emotional disorders are more varied, but there is little evidence for any rise in rates of anorexia nervosa. Although some contributors to these trends have been identified, much remains to be learned about the key risks involved.
  
  
  CONCLUSIONS
  Monitoring time trends in child and adolescent mental health is essential for service planning; knowledge of changing trends can also provide important pointers to potential risk factors. Current data sources allow relatively reliable tracking of trends in some areas, but remain severely limited in others. Further research is needed to understand the mechanisms underlying recently identified trends in child and adolescent mental health.
authors.affiliation: MRC Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, King's College London, London, UK. b.maughan@iop.kcl.ac.uk
authors.forename: Barbara
authors.initials: B
authors.lastname: Maughan
authors.forename: Alessandra C
authors.initials: AC
authors.lastname: Iervolino
authors.forename: Stephan
authors.initials: S
authors.lastname: Collishaw