Electronic Thesis and Dissertation Repository

Thesis Format

Integrated Article


Doctor of Philosophy


Epidemiology and Biostatistics


Anderson, Kelly K.

2nd Supervisor

Thind, Amardeep



Our objectives were to: (1) evaluate the current literature on the epidemiology of mood or anxiety disorders among migrant groups; (2) assess how current tools for measuring mood or anxiety disorders at the population level influence our understanding of the epidemiology by a) analyzing the concordance between two commonly used population measures, and b) using a Bayesian analysis to create a combined estimate using both measures; (3) estimate the prevalence and effects of potential risk factors on the prevalence of mood or anxiety disorders among first-generation migrant groups compared to the general population in Ontario. We conducted a systematic review and multiple secondary data analyses using data available from ICES to complete our objectives. Data sources included the 2012 Canadian Community Health Survey–Mental Health, in addition to health administrative data sources in Ontario. Canadian evidence suggests the prevalence of mood or anxiety disorders was consistently lower among migrant groups compared to estimates from the general population. Our findings suggest there was low concordance between survey and administrative data derived estimates of mood or anxiety disorders among migrant and non-migrant groups. Our Bayesian analysis suggests that the true prevalence of mood or anxiety disorders may lie between estimates derived from administrative and survey data. Our findings also indicate that the relationship between migration and mood or anxiety disorders is variable depending on migrant specific risk factors including migrant class and region of birth. Our work highlights the importance of contextualizing population-level data sources to accurately inform policy.

Summary for Lay Audience

One in five Canadians are foreign born. Experiences prior to, during, and following migration can affect mental health. Two of the most common mental disorders are depression and anxiety disorders, which contribute to approximately three quarters of all mental health care visits in Canada. Measuring the occurrence of depression and anxiety disorders at the population level is challenging, and typically is done using data from either surveys or regularly collected health administrative data, which include information on visits to physicians, emergency departments, and to the hospital. Prior Canadian evidence suggests that migrant groups have lower amounts of depression and anxiety disorders compared to the general population, however, these findings rely on survey data. We identified a need to study this relationship using health administrative data, and to see whether people identified as having depression or anxiety in surveys were also identified in health administrative data. Our findings suggest there are large differences between survey and health administrative data. Specifically, surveys may be providing an overestimate of depression and anxiety in the population, while health administrative data may be providing an underestimate. The findings from our study of depression and anxiety among migrants, using health administrative data alone, revealed that while migrant groups had lower depression and anxiety disorders compared to the general population, this relationship was dependent on migrant specific factors including region of birth and migrant class. We found that refugee groups had the highest estimates of depression and anxiety disorders compared to other migrant groups. Our findings highlight the complexity between migration and depression and anxiety. Migrant status alone provides an incomplete picture of these relationships. We must continue to make use of the strengths of available population level data to help unravel the complexities of these relationships. Providing detailed estimates of depression and anxiety disorders are key to help inform policy to design programs to support high risk migrant groups. Ensuring new Canadians mental health care needs are addressed is an essential component of ensuring their success in Canada and the success of the nation as a whole.

Available for download on Friday, October 22, 2021