American Journal of Epidemiology Advance Access originally published online on July 16, 2009
American Journal of Epidemiology 2009 170(4):484-493; doi:10.1093/aje/kwp160
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ORIGINAL CONTRIBUTIONS |
Objective and Perceived Ethnic Density and Health: Findings From a United Kingdom General Population Survey
Correspondence to Dr. Mai Stafford, Department of Epidemiology and Public Health, University College London, 1-19 Torrington Place, London WC1E 6BT, United Kingdom (e-mail: m.stafford{at}ucl.ac.uk).
Received for publication October 24, 2008. Accepted for publication May 15, 2009.
Studies indicate an ethnic density effect, whereby an increasing proportion of persons of the same ethnicity as oneself (co-ethnics) in one's area of residence is associated with reduced risk of morbidity among ethnic minorities, though evidence is mixed. Measures of ethnic density are commonly taken from small-area census data using predefined categories of ethnicity. In a United Kingdom study, the authors compared these measures with perceived ethnic density, based on self-reported proportion of co-ethnics in the area. Using 2005 Home Office Citizenship Survey data linked to the 2001 United Kingdom Census, they found moderate-sized correlations between perceived and measured ethnic density which varied across ethnic groups (r = 0.34–0.65). Perceived ethnic density underestimated measured levels for whites and overestimated measured levels for ethnic minorities. Compared with participants in areas where less than half of residents were co-ethnics, those reporting a perceived ethnic density of more than half tended to have less limiting long-term illness (for all ethnic minorities combined, odds ratio = 0.81, 95% confidence interval: 0.63, 1.04) after adjustment for age, sex, socioeconomic position, ethnicity, area deprivation, and measured ethnic density. After adjustment for perceived ethnic density, there was no evidence of a protective association for measured ethnic density, except for Caribbeans. Perceived ethnic density may reflect individual experiences of frequency and intensity of contact with co-ethnics, which may explain why it was more consistently related to lower morbidity risk.
ethnic groups; health status disparities; residence characteristics
Abbreviations: HOCS, Home Office Citizenship Survey; PSU, primary sampling unit