caa a22 4500 606178856 CHVBK 20210128100758.0 cr unu---uuuuu 210128e20151201xx s 000 0 eng 10.1007/s11136-015-1026-3 doi (NATIONALLICENCE)springer-10.1007/s11136-015-1026-3 Examining the relationship between health-related quality of life and increasing numbers of diagnoses [Elektronische Daten] [Mathias Barra, Liv Augestad, David Whitehurst, Kim Rand-Hendriksen] Purpose: Little is known about estimating utilities for comorbid (or ‘joint') health states. Several joint health state prediction models have been suggested (for example, additive, multiplicative, best-of-pair, worst-of-pair, etc.), but no general consensus has been reached. The purpose of the study is to explore the relationship between health-related quality of life (HRQoL) and increasing numbers of diagnoses. Methods: We analyzed a large dataset containing respondents' ICD-9 diagnoses and preference-based HRQoL (EQ-5D and SF-6D). Data were stratified by the number of diagnoses, and mean HRQoL values were estimated. Several adjustments, accounting for the respondents' age, sex, and the severity of the diagnoses, were carried out. Our analysis fitted additive and multiplicative models to the data and assessed model fit using multiple standard model selection methods. Results: A total of 39,817 respondents were included in the analyses. Average HRQoL values were represented well by both linear and multiplicative models. Although results across all analyses were similar, adjusting for severity of diagnoses, age, and sex strengthened the linear model's performance measures relative to the multiplicative model. Adjusted R 2 values were above 0.99 for all analyses (i.e., all adjusted analyses, for both HRQoL instruments), indicating a robust result. Conclusions: Additive and multiplicative models perform equally well within our analyses. A practical implication of our findings, based on the presumption that a linear model is simpler than an additive model, is that an additive model should be preferred unless there is compelling evidence to the contrary. The Author(s), 2015 EQ-5D nationallicence SF-6D nationallicence Comorbidity nationallicence Health-state utility value nationallicence Health-related quality of life nationallicence Barra Mathias Health Services Research Center, Akershus University Hospital, Postboks 1000, 1478, Lørenskog, Akershus, Norway aut Augestad Liv Health Services Research Center, Akershus University Hospital, Postboks 1000, 1478, Lørenskog, Akershus, Norway aut Whitehurst David Faculty of Health Sciences, Simon Fraser University, Burnaby, BC, Canada aut Rand-Hendriksen Kim Health Services Research Center, Akershus University Hospital, Postboks 1000, 1478, Lørenskog, Akershus, Norway aut Quality of Life Research Springer International Publishing 24/12(2015-12-01), 2823-2832 0962-9343 24:12<2823 2015 24 11136 https://doi.org/10.1007/s11136-015-1026-3 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s11136-015-1026-3 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Barra Mathias Health Services Research Center, Akershus University Hospital, Postboks 1000, 1478, Lørenskog, Akershus, Norway aut NATIONALLICENCE 700 1- Augestad Liv Health Services Research Center, Akershus University Hospital, Postboks 1000, 1478, Lørenskog, Akershus, Norway aut NATIONALLICENCE 700 1- Whitehurst David Faculty of Health Sciences, Simon Fraser University, Burnaby, BC, Canada aut NATIONALLICENCE 700 1- Rand-Hendriksen Kim Health Services Research Center, Akershus University Hospital, Postboks 1000, 1478, Lørenskog, Akershus, Norway aut NATIONALLICENCE 773 0- Quality of Life Research Springer International Publishing 24/12(2015-12-01), 2823-2832 0962-9343 24:12<2823 2015 24 11136