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Temporal Trends in the Distribution of Child and Youth Mental Ill-Health from 1983 to 2023

Information Box Group


Harmonize data from four epidemiologic studies representative of the general population of Ontario children and youth aged 4-15 years over a 40-year period (1983-2023):

  • To quantify changes in levels of child and youth mental health symptoms over time, and
  • To identify population subgroups who show differential change over time in levels of mental health symptoms


Data from four studies will be used: 1983 Ontario Child Health Study (1983 OCHS); 1998 National Longitudinal Study of Children and Youth (NLSCY); 2014 OCHS; and 2023 Canadian Health Survey on Children and Youth (CHSCY).


Uncertainty about the constancy or rate of change in mental ill-health in young people impedes public health decision-making and service planning. Evidence from the study will quantify the magnitude of change across the population of Ontario children and youth, and the extent to which population subgroups have demonstrated differential change over a 40-year period. These results will provide high-quality evidence to better inform population and public health decision-making thereby improving outcomes for young people.