One in five Ontario children and youth suffer from a mental disorder, but less than one-third have had contact with a mental health-care provider, says the Ontario Child Health Study (OCHS).

Although those overall results echo a similar study from 1983, the new study found a much larger proportion of children and youth with a disorder had contact with other health providers and in other settings, most often through schools.

The new study, called the 2014 OCHS for when data collection started, found that the patterns of prevalence among different sexes and age groups have changed. Hyperactivity disorder in boys 4 to 11 years old jumped dramatically from 9% to 16%, but there has been a substantial drop in disruptive behavior among males 12 to 16 years old from 10% to 3%. There has been a steep increase in anxiety and depression among both male and female youth from 9% to 13%.

At the same time, there was a significant rise in perception of need for professional help with mental health disorders, rising from 7% in the original OCHS in 1983 to 19% in the 2014 OCHS. However, the study authors say it is difficult to estimate whether it is tied to the growing prominence of anti-stigma and mental health awareness campaigns over the past three decades.

In 30 years, the prevalence of any disorder increased in communities with a population of 1,000 to 100,000, rather than large urban areas, and there is strong evidence that poor children are more likely to have a disorder if their neighborhood is one where violence is more common. The study also found that in the past year more than 8% of youth thought about suicide, and 4% reported a suicide attempt.

The 2014 OCHS study included 10,802 children and youth aged 4 to 17 in 6,537 families. It replicated and expanded on the landmark 1983 Ontario Child Health Study of 3,290 children in 1,869 families. The Canadian Journal of Psychiatry has simultaneously published eight papers on different aspects of the 2014 OCHS results.

“This is a very robust study we feel represents the situation in Canada,” said Michael Boyle, co-principal investigator of the study. “That means there are more than a million Canadian children and youth with a mental health problem. This needs to be addressed.” Co-principal investigator Kathy Georgiades added, “This study underscores the continued need for effective prevention and intervention programs.”