Doan, Natalie2025-08-272025-08-272025-08-272025-07-21https://hdl.handle.net/10012/22296It is well-acknowledged that diet quality differs across socioeconomic position (SEP). However, it is unclear how SEP dimensions intersect to shape diet quality. My dissertation uses an intersectional approach to identify differences in diet quality across SEP dimensions and contexts. The primary objectives of my dissertation research were: (1) to identify individual/household SEP intersections that best predicted lower and higher diet quality among a population-based sample of adults in Canada; (2) to assess whether four dimensions of neighbourhood deprivation were independently and/or jointly associated with diet quality among a nationally representative sample of adults in Canada; and (3) to compare associations between three SEP indicators (educational attainment, perceived income adequacy, household food insecurity) and diet quality between adults in Canada and the United States. In a conditional random forest analysis, I identify educational attainment and Indigenous identity and race/ethnicity as the most important intersectional predictor of diet quality among adults in Canada. By examining four dimensions of neighbourhood deprivation, I find significant interactions that suggest associations between living in a neighbourhood with less material resources and lower HEI-2015 scores was stronger in areas with a smaller proportion of recent immigrants/visible minorities and non-working individuals. In a cross-country comparison, I find that associations between SEP (educational attainment, perceived income adequacy, and household food insecurity) and diet quality did not differ between Canada and the United States. Overall, this dissertation demonstrates how an intersectional approach to quantitative health research can be used to draw attention to the complex and context-dependent nature of inequities in diet quality.enintersectionalitypublic healthmachine learningbiostatisticsneighbourhood deprivationcross-country comparisondiet qualityDoctoral Thesis