One of the key challenges in the analysis and interpretation of health survey data is the comparability of answers to questions that use ordered categorical response scales. Even for instruments with established reliability and validity, the problem of cross-population comparability remains as a consequence of differences in the ways that individuals understand and use the available responses for a given question. This paper describes the use of vignettes as a source of additional information that may be used in conjunction with the hierarchical ordered probit (HOPIT) model in order to adjust self-reported responses into cross-population measures. The authors present the concept of vignettes generally and give examples of vignettes from the WHO Multi-Country Household Survey Study, then explore a range of practical issues on the design, application and formal evaluation of vignettes.

   Murray et al. have outlined a series of different strategies for enhancing cross-population comparability of survey results through the formal analysis of systematic cutpoint shifts. One way to address this problem, whether it arises in self-reported or physician-assessed data, is by fixing the levels of the unobserved latent variable of interest in order to isolate cutpoint differences as the source of variation in assessments of these levels. In combination with new statistical models, the incorporation of this exogenous information allows estimation of variation in cutpoints attributable to socio-demographic or other factors. This paper we describes the application of this new approach to the publically-available National Health and Nutrition Examination Survey dataset. The objective of this paper is to examine whether sex, race/ethnicity and income affect self-reports and physician-assessments of mobility through predictable differences in the use of categorical responses.

   In order to address some of the fundamental empirical and methodological questions pertaining to health state valuations, WHO has embarked on a series of data collection and analytical efforts on health state valuations as a key component of its research agenda on measuring health. This paper provides an overview of the ongoing work at WHO on health state valuations in summary measures of population health. The authors begin by describing the conceptual and analytical framework for health state valuations, provide a summary of the health state valuation component of the WHO Multi-Country Survey Project, highlight the major results from this effort and end with a discussion of ongoing improvements and future directions for this work.