Ethnicity as a variable in epidemiological research

Abstract

Ethnicity is used increasingly as a key variable to describe health data, and ethnic monitoring in the NHS will further stimulate this trend. We identify four fundamental problems with ethnicity in this type of research: the difficulties of measurement, the heterogeneity of the populations being studied, lack ofclarity about the research purpose ofthe research, and ethnocentricity affecting the interpretation and use ofdata. Ethnicity needs to be used carefully to be a useful tool for health research. We make nine recommendations for future practice, one of which is that ethnicity and race should be recognised and treated as distinct concepts.

Ethnic variations in mortality in pre-school children in Denmark, 1973–2004

“…It is a commonly used definition, and while it is crude it has the strength of being easy to measure and stable over time. Some argue that self-reported ethnicity may be the most appropriate measure ahead of race and religion 34 , but country of origin was the only available variable in Danish registries. It should be noted that the association between (our definition of) ethnicity and the risk of U5-mortality does not itself establish causality.…”

Does the pulse pressure in people of European, African and South Asian descent differ? A systematic review and meta-analysis of UK data

“…38 The heterogeneity between South Asian descent and African populations has long been emphasized but, with few exceptions, ignored. 2,39,40 The differences observed between Indian people on the one hand and Bangladeshi and Pakistani people on the other clearly indicate the importance of studying South Asian groups separately rather than combining them. Indian population is also a heterogeneous group.…”

“…The lower PP in Bangladeshi and Pakistani people is, however, in contrast to their higher cardiovascular mortality in the UK. More work on this topic is needed in which the heterogeneity within South Asian 39 and African descent populations 40 is recognized.…”

“…Overall weighted mean difference (WMD) in PP was 1.68 (95% confidence interval: [0.38, 2.98 mm Hg]; P ¼ 0.01) in men and 2.01 ([0. 39,3.63 mm Hg]; Po0.001) in women. South Asian men (n ¼ 7 studies) had a lower mean PP than White men (À1.94; [À3.56, -0.32 mm Hg]; P ¼ 0.02), whereas no significant difference was found between South Asian and White women (n ¼ 5 studies) (À0.40;…”

Is the blood pressure of people from African origin adults in the UK higher or lower than that in European origin white people? A review of cross-sectional data

“…Such inconsistency prompted us to undertake this research study. We apply the concept of ethnicity as discussed by Senior and Bhopal, 2 and given in the glossary.…”