A systematic review of the literature on the development of condition-specific preference-based measures of health

Abstract

Background. Health state utility values (HSUVs) are required to calculate quality-adjusted life-years (QALYs). They are frequently derived from generic preference-based measures of health. However, such generic measures may not capture health attributes of relevance to specific conditions. In such cases, a condition-specific preference-based measure (CSPBM) may be more appropriate. Objective. This systematic review aimed to identify all published accounts of developing CSPBMs, to describe and appraise the methods used. Method. A systematic search (of Embase, Medline, PsycINFO, Web of Science, the Cochrane Library, CINAHL, EconLit, ASSIA and the Health Management Information Consortium database) was undertaken to identify published accounts of CSPBM development up to July 2015. Studies were reviewed to investigate the methods used to design classification systems, estimate HSUVs, and validate the measures. Results. Eighty-six publications were identified, describing 51 CSPBMs. Around two-thirds of these were QALY measures; the remainder were designed for clinical decision-making only. Classification systems for 33 CSPBMs were derived from existing instruments; 18 were developed de novo. HSUVs for 34 instruments were estimated using a ‘composite’ approach, involving statistical modelling; the remainder used a ‘decomposed’ approach based on multi-attribute utility theory. Half of the papers that described the estimation of HSUVs did not report validating their measures. Conclusion. Various methods have been used at all stages of CSPBM development. The choice between developing a classification system de novo or from an existing instrument may depend on the availability of a suitable existing measure, while the choice between a decomposed or composite approach appears to be determined primarily by the purpose for which the instrument is designed. The validation of CSPBMs remains an area for further development.