Anchors—A Way? Using Anchoring Vignettes to Assess Group Differences in Self-Rated Health

Grol Prokopczyk, Hanna, Jeremy Freese, and Robert Hauser
Working paper no. 2010-09

Abstract

This paper identifies a potentially serious problem with the widely used self-rated health (SRH) survey item: that different groups (e.g., different nationalities) have systematically different ways of using the item’s response categories. Analyses based on unadjusted SRH may thus produce misleading or entirely erroneous results. We explore anchoring vignettes as a possible solution to this problem. Using vignettes specifically designed to calibrate the SRH item, and data from the Wisconsin Longitudinal Study, we show how certain demographic and health-related factors, including sex and education, predict differences in rating styles. Such differences, when not adjusted for statistically, may be sufficiently large to lead to mistakes in rank orderings of groups: in our sample, models that fail to account for women’s greater health-optimism show—incorrectly—that women have better SRH than men. Vignette-based adjustment may reduce risk of such errors. Implications for future research using anchoring vignettes are discussed.