Studies involving populations are often questioned as to the homogeneity of their samples relative to race and ethnicity. Such questioning is justified because sample heterogeneity can increase the variability of and even mask results. These two concepts (race and ethnicity) are often confused despite their subtle differences. Race includes phenotypic characteristics such as skin color whereas ethnicity also encompasses cultural factors such as nationality, tribal affiliation, religion, language and traditions of a particular group. Despite the widespread use of the term "race", geneticists are increasingly convinced that race is much more a social than a scientific construct.
Ethnicity and health; Distribution by race or ethnicity; Ethnic groups
