IDENTIFYING ANCESTRY - THE RELIABILITY OF ANCESTRAL IDENTIFICATION INTHE UNITED-STATES BY SELF, PROXY, INTERVIEWER, AND FUNERAL DIRECTOR

We examined consistency in the classification of ancestry by self, pro xy, interviewer, and funeral director (on a death certificate) in a sa mple of the U.S. population-the First National Health and Nutrition Ex amination Survey and Epidemiologic Follow-up. Among study subjects for whom comparable ethnic identity options were available at both interv iews, 58% of subjects specified the same identity at two times. Person s who specified four different ethnic backgrounds were 3.4 times as li kely to change their identity over time as persons specifying only one background. Self classification of ancestry at initial interview was consistent with proxy reports at follow-up for 55% of subjects for who m proxy information was available. Comparison of the self-classificati on of ancestry with the classification of race by interviewers and by funeral directors indicates high consistency for Whites and Blacks and low consistency for American Indians. The ''measurement'' of ancestry (that is, race or ethnicity) is critical to the understanding and eli mination of differences in health status among racial/ethnic populatio ns, but the low reliability of these measures over time and across obs ervers complicates the analysis and interpretation of health statistic s by ancestry, particularly for populations other than White or Black.