Anchoring bias in face-to-face Time-Trade-Off valuations of health states

Objective To test whether anchoring (a cognitive bias) occurs during face-to-face interviews to value health states by Time-Trade-Off.Methods 147 Colombian subjects (111 males, 36 females) valued five EQ-5D health states better than death during a face-to-face interview. Subjects were randomly assigned to two different starting points.Results Shapiro-Wilk test discarded normality, while non-parametric tests, including Kolmogorov-Smirnov and Wilcoxon–Mann-Whitney, showed that anchoring was significant in four out of five health states. A higher starting point increased the elicited value by 15 %-188 %. The size of the anchoring effect was not uniform among health states.Conclusion Anchoring effects may bias face-to-face Time Trade-Off valuations. The size of the anchoring effect is relevant enough for health policy.

• Autores: García Molina, Mario; Chicaíza Becerra, Liliana Alejandra
• Tipo de recurso: Article of journal
• Fecha de publicación: 2017
• Institución: Universidad Nacional de Colombia
• Repositorio: Universidad Nacional de Colombia
• Idioma: spa
• OAI Identifier: oai:repositorio.unal.edu.co:unal/65474
• Acceso en línea: https://repositorio.unal.edu.co/handle/unal/65474; http://bdigital.unal.edu.co/66497/
• Palabra clave: 36 Problemas y servicios sociales, asociaciones / Social problems and social services; 61 Ciencias médicas; Medicina / Medicine and health; Heuristics; cost-benefit analysis; outcome assessment (health care); observer variation; bias; methods; Heurística; análisis costo-beneficio; evaluación de resultado; variaciones dependientes del observador; sesgo; métodos
• Rights: openAccess
• License: Atribución-NoComercial 4.0 Internacional