The reliability of adult self-reported height: The role of interviewers

Surveys serve as an important source of information on key anthropometric characteristics such as body height or weight in the population. Such data are often obtained by directly asking respondents to report those values. Numerous studies have examined measurement errors in this context by comparing reported to measured values. However, little is known on the role of interviewers on the prevalence of irregularities in anthropometric survey data. In this study, we explore such interviewer effects in two ways. First, we use data from the US National Health and Nutrition Examination Survey and the UK Household Longitudinal Study to evaluate whether differences between reported and measured values are clustered within interviewers. Second, we investigate changes in adult self-reported height over survey waves in two German large-scale panel surveys. Here, we exploit that height should be constant over time for the majority of adult age groups. In both analyses, we use multilevel location-scale models to identify interviewers who enhance reporting errors and interviewers for whom unlikely height changes over waves occur frequently. Our results reveal that interviewers can play a prominent role in differences between reported and measured height values and changes in reported height over survey waves. We further provide an analysis of the consequences of height misreporting on substantive regression coefficients where we especially focus on the role of interviewers who reinforce reporting errors and unlikely height changes.