Use of anchoring vignettes to evaluate health reporting behavior amongst adults aged 50 years and above in Africa and Asia – testing assumptions

Abstract

BackgroundComparing self-rating health responses across individuals and cultures is misleading due to different reporting behaviors. Anchoring vignettes is a technique that allows identifying and adjusting self-rating responses for reporting heterogeneity (RH).ObjectiveThis article aims to test two crucial assumptions of vignette equivalence (VE) and response consistency (RC) that are required to be met before vignettes can be used to adjust self-rating responses for RH.DesignWe used self-ratings, vignettes, and objective measures covering domains of mobility and cognition from the WHO study on global AGEing and adult health, administered to older adults aged 50 years and above from eight low- and middle-income countries in Africa and Asia. For VE, we specified a hierarchical ordered probit (HOPIT) model to test for equality of perceived vignette locations. For RC, we tested for equality of thresholds that are used to rate vignettes with thresholds derived from objective measures and used to rate their own health function.ResultsThere was evidence of RH in self-rating responses for difficulty in mobility and cognition. Assumptions of VE and RC between countries were violated driven by age, sex, and education. However, within a country context, assumption of VE was met in some countries (mainly in Africa, except Tanzania) and violated in others (mainly in Asia, except India).ConclusionWe conclude that violation of assumptions of RC and VE precluded the use of anchoring vignettes to adjust self-rated responses for RH across countries in Asia and Africa.

Does reporting behaviour bias the measurement of social inequalities in self-rated health in Indonesia? An anchoring vignette analysis

“…We also note that the validity of the anchoring vignette method hinges critically on the maintenance of both vignette equivalence and response consistency assumptions. A number of studies have investigated the plausibility of these assumptions; some have found positive supports [ 19 , 26 , 31 ], while others report possible violations [ 5 , 6 , 8 , 13 ]. In this study, there is always the possibility that these assumptions are violated.…”

“…Anchoring vignette is a promising method that offers a direct way of handling interpersonal incomparability in self-report measure. Although methodologists have extended the original anchoring vignette method [ 19 ] to accommodate more complex situations [ 4 , 6 , 17 , 23 , 24 , 31 , 36 ], adequate attention should also be given to the fundamental matters of question wording [ 1 , 13 ] and ordering [ 7 , 14 ]. We believe that, given its cost-effectiveness and feasibility in large-scale surveys, SRH and anchoring vignette have the potential to play a greater role in public health research in now-decentralised Indonesia, where more than 500 local administrations must struggle with a scarcity of competent health workers [ 27 , 33 ] as well as with the high cost of collecting objective health measures.…”

Variations in disability and quality of life with age and sex between eight lower income and middle-income countries: data from the INDEPTH WHO-SAGE collaboration

“…Previous work on related vignettes (covering mobility and cognition) suggests that although the psychometric performance of vignettes in WHO-SAGE is imperfect at predicting anchoring in absolute terms, the vignettes still provide information on how individuals order severity of conditions, particularly for self-care. 25 The vignettes covered: a person able to wash, bathe and dress himself slowly; a person housebound because of arthritis who cannot dress and needs help with washing; a person able to self-care except for occasional help with bathing and dressing when he has back pain; and a person requiring help with all care because of paralysis from the neck down. For each vignette, we asked a question on ability to self-care and a question on maintaining appearance, corresponding to questions asked on self-care and appearance within WHODAS-II.…”

Differential item functioning in quality of life measurement: An analysis using anchoring vignettes

“…Provided that two key identifying assumptions hold, namely response consistency (RC) and vignette equivalence (VE), these ratings can reveal what the response categories truly mean for respondents, and can therefore be used to identify and adjust for DIF. The approach has been used in a number of applications including political efficacy (King et al, 2004), job,income,life, and health satisfaction (Angelini, Cavapozzi, Corazzini, & Paccagnella, 2014;Bertoni, 2015;Crane, Rissel, Greaves, & Gebel, 2016;Kapteyn, Smith, & Van Soest, 2013;Kristensen & Johansson, 2008) and general and specific dimensions of health Dowd & Todd, 2011;Grol-Prokopczyk et al, 2011;Hirve et al, 2013;Molina, 2016;Peracchi & Rossetti, 2012).…”