Mapping the University of Washington Quality of life questionnaire onto EQ-5D and HUI-3 indices in patients with head and neck cancer

Head Neck. 2020 Mar;42(3):513-521. doi: 10.1002/hed.26031. Epub 2019 Nov 24.

Abstract

Background: There is no mechanism to predict health utility (HU) values from the University of Washington Quality of Life Questionnaire (UWQoL) scores. We sought to develop a mapping algorithm capable of using UWQoL data to approximate HU scores.

Methods: Outpatients with head and neck cancer completed the UWQoL, EQ-5D, and the Health Utilities Index-Mark 3 (HUI-3). Results of the UWQoL were mapped onto both EQ-5D and HUI-3 scores using ordinary least-squares regression models. Two-part models were explored. The predictive power of the model was assessed using 10-fold cross-validation.

Results: A total of 209 patients were recruited. The reduced model converting UWQoL data into EQ-5D scores performed best (adjusted R2 = 0.628, root mean square error = 0.076). Both models demonstrated construct validity by discriminating between clinical indices of disease severity.

Conclusions: The abovementioned algorithms enable researchers to perform health economic evaluations with existing UWQoL data in cases where prospectively collected HU values are not available.

Keywords: EQ-5D; QALYs; University of Washington Quality of life questionnaire; cross-walking; head and neck cancer (HNC); health state utility values (HSUVs); health utilities index mark 3; health-related quality of life (HRQoL); mapping algorithms; multi-attribute utility instruments (MAUIs); preference-based measures.