Prevalence of mental illness

Epidemiological research has shown that between 3% and 18% of children have a psychiatric disorder causing significant functional impairment (reasons for these widely divergent prevalence

Prevalence

In epidemiology, the prevalence of a health-related state in a statistical population is defined as the total number of cases of the risk factor in the population at a given time, or the total number of cases in the population, divided by the number of individuals in the population...

 rates are discussed below) and Costello and colleagues have proposed a median prevalence estimate of 12%. Using a different statistical method, Waddell and colleagues propose a prevalence rate for all mental disorders in children of 14.2%.

Developmental epidemiology

Developmental epidemiology seeks to "disentangle how the trajectories of symptoms, environment, and individual development intertwine to produce psychopathology

Psychopathology

Psychopathology is the study of mental illness, mental distress, and abnormal/maladaptive behavior. The term is most commonly used within psychiatry where pathology refers to disease processes...

".

Socio-economic influences

Mental illness in childhood and adolescence is associated with parental unemployment, low family income, being on family income assistance, lower parental educational level, and single-parent, blended or stepparent families.

Methodological issues

Epidemiological research has produced widely divergent estimates, depending on the nature of the diagnostic method (e.g. structured clinical interview, unstrutured clinical interview, self-report or parent-report questionnaire), but more recent studies using DSM-IV-based structured interviews produce more reliable estimates of clinical "caseness". Past research has also been limited by inconsistent definitions of clinical disorders, and differing upper and lower age limits of the study population. Changing definitions over time have given rise to spurious evidence of changing prevalence of disorders. Furthermore, almost all epidemiological surveys have been carried out in Europe, North America and Australia, and the cross-cultural validity of DSM criteria have been questioned, so it is not clear to what extent the published data can be generalized to developing countries.

See also

• Child and adolescent psychiatry
  Child and adolescent psychiatry
  The branch of psychiatry that specializes in the study, diagnosis, treatment, and prevention of psychopathological disorders of children, adolescents, and their families, child and adolescent psychiatry encompasses the clinical investigation of phenomenology, biologic factors, psychosocial factors,...