WU AND SCHIMMELE RESPOND

Abstract

McCarthy and associates observe that analyses of racial/ethnic health disparities in countries with substantial recent immigrant populations must consider the effects of nativity, for this factor influences health differences. We acknowledge this crucial observation, and indeed we are familiar with the literature on healthy migrants. For example, an up-to-date Statistics Canada report indicates that foreign-born individuals report fewer chronic conditions than nonimmigrants.1 This foreign-born advantage persists after the introduction of controls for age, education, and income. Of interest to McCarthy and others, this report also observes that health risk behaviors (e.g., tobacco consumption) differ between immigrants and nonimmigrants, but that these differences cannot account for the differences in health outcomes. We have completed research—also using nationally representative data—into the healthy migrant (or immigrant) effect, specifically testing whether this phenomenon applies to depression and whether the effect on depression varies with length of residence.2 Our results confirmed that the healthy migrant advantage with regard to depression appears to be concentrated among recent, non-European immigrants, especially Asians, and therefore may not be generalizable. Other research shows a similar pattern for chronic conditions and disabilities.3 In other words, the so-called healthy migrant effect may be spurious and could actually represent a socio-cultural health effect. McCarthy and colleagues remark that we should be more cautious in our speculative explanation for the superior functional health of Canadian Blacks compared with US Blacks, considering that national differences in immigration histories may confound our findings. We agree that differences in health care policies may not hold the answer, but data and space limitations prevented us from giving a more satisfying explanation. In any case, modeling the healthy migrant effect is virtually impossible without data from source countries, which are necessary to determine whether individual health status is a consistent selection factor in the international migration process. Our results do, however, confirm that the reported functional health of Canadian Blacks is better after control for immigrant status. We therefore rule out the healthy migrant effect as a valid explanation for why Canadian Blacks are healthier than the Canadian average. Moreover, US research demonstrates that Black–White health differences are attenuated after control for socioeconomic status.4 This finding lends indirect support to our argument that Canada’s single-payer health insurance system is a plausible reason for health differences between Canadian and US Blacks. In the United States, in contrast to Canada, there is obviously a robust correlation between health care access and socioeconomic status.