Electronic Thesis and Dissertation Repository

Thesis Format

Integrated Article

Degree

Doctor of Philosophy

Program

Education

Supervisor

Stewart, Shannon L.

2nd Supervisor

King, Colin

Co-Supervisor

Abstract

The prevalence of mental health disorders among young persons in Canada is high. Approximately 1 in 5 will experience a mental health concern. This estimate does not capture individuals who experience disruptive symptoms but fail to meet diagnostic thresholds. In Canada, the provision of mental health supports is fragmented across service sectors and lacks a standardized governance to identify, prioritize and triage youth in need of assistance. This results in a paucity of information about service users, especially as it relates to autistic youth. This three-paper dissertation utilized multi-sectoral assessment tools to describe treatment-seeking

youth in Ontario, Canada in terms of service complexity and mental health resource intensity. The first paper examined the association between sex, age, caregiver distress, finance, co-occurring conditions, intellectual disability and evaluated health status on mental health service complexity among autistic youth. Results indicated that older youth, females, several co-occurring conditions, no intellectual disability and longer durations of programming resulted in greater service complexity. The second paper explored classes of health risk behaviours related to alcohol and substance use among youth. Three classes of health risk behaviours emerged: (i) non-use, (ii) cannabis use and (iii) polysubstance use. Additionally, sex, age, polyvictimization, a diagnosis of autism spectrum disorder, family functioning, peer conflict and school engagement were associated with class membership. The third paper examined classes of health risk behaviours specifically among autistic youth and their relationships to mental health state indicators and resource intensity. The results indicated three classes of health risk behaviours: (i) recent smoking and substance use, (ii) non-use and (iii) recent cannabis use. Additionally, levels of sleep difficulties and externalizing symptoms differed between classes, whereas communication difficulties and internalizing symptoms did not. Female youth and recent cannabis users required higher mental health resource intensity compared to male peers and non-users. The dissertation concludes by discussing the implications of the overall findings for research and for mental health policy, specifically as it relates to the integration of supports for youth in Ontario, Canada.

Summary for Lay Audience

Mental health difficulties among young persons in Canada is a significant public health concern. The delivery of mental health supports lacks a common method, leading to challenges in the prioritization of youth for services and results in a lack of information about service users. This is particularly problematic for autistic youth who remain an understudied client demographic. This has led to a growing body of science that seeks to understand how to strengthen the existing pediatric mental health care system while obtaining information about service users.

In an effort to close the knowledge gap, this three-paper dissertation focused on the complexity of mental health services and resource needs among young persons in Ontario. The first paper revealed older youth, females, those with multiple co-occurring conditions, no intellectual disability, and longer program durations require more complex mental health services. In the second paper, three unique groups of health risk behaviours were identified: non-use, cannabis use and use of multiple substances. Additionally, sex, age, polyvictimization, a diagnosis of autism spectrum disorder, family functioning, peer conflict and school engagement were associated with group membership. For example, youth with the greatest family dysfunction and peer conflict belonged to the group characterized by multiple substance use; providing insight into the complexity of health risk behaviours.

The third paper delves into specific health risk behaviours exhibited by autistic youth and their relationships to mental health outcomes and resource intensity. Again, three groups were identified: recent smoking and substance use, non-use, and recent cannabis use. Notably, female youth and recent cannabis users demonstrated a higher need for mental health resource intensity compared to males and non-users. An association with sleep difficulties and outward behavioural problems were observed among groups, while communication difficulties and internalizing symptoms exhibited no notable change. The findings of this dissertation have implications for research on youth mental health and inform policy, particularly concerning the integration of supports. By uncovering the complexities of mental health service delivery and showcasing the differing health risk behaviour groups, this research contributes to the development of tailored interventions addressing the specific needs of youth. The identification of unique challenges faced by autistic youth is a crucial step towards the implementation of inclusive and effective support for this understudied group.

Creative Commons License

Creative Commons Attribution 4.0 License
This work is licensed under a Creative Commons Attribution 4.0 License.

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