An Ecologic Analysis of Childhood Cancer Mortality in Ontario 1976 -1985

Abstract

<p>Geographical variation in human cancer has been well documented among the populations of various areas. Past research on childhood cancer incidence and mortality, however, is inconclusive regarding the spatial variability and associated determinants of cancer in this population sub-group. This thesis examines childhood cancer mortality in Ontario from 1976 to 1985. An initial discussion of the differences between childhood and adult cancer, an overview of previous investigations of geographical variations in childhood cancer and a review of the broad range of correlates of pediatric cancer considered in the literature are provided. Then, using the ecologic study design, county level mortality rates were analysed for all sites combined over the ten year period for ages 0 to 19 by gender. Geographic analysis using maps, spatial autocorrelation, correlation and regression analyses, and an evaluation of regression residuals were used to examine the relationship between childhood cancer standardized mortality ratios and a set of 17 environmental and socio-demographic variables, including: ethnicity, urbanization, parental occupation and income.</p> <p>The specific objectives of the research were: (a) to describe county level rates of childhood cancer mortality in Ontario for the period 1976 to 1985; (b) to analyse spatial variations in pediatric cancer mortality; (c) to determine to what extent those variations are related to variations in selected ecologic variables; and, (d) to comment on future directions for research in childhood cancer epidemiology.</p>