Mapping the Minnesota Living with Heart Failure Questionnaire (MLHFQ) onto the Assessment of Quality of Life 8D (AQoL-8D) utility scores

Abstract
Purpose The Minnesota Living with Heart Failure Questionnaire (MLHFQ) is a widely used condition-specific measure of quality of life (QoL) in patients with heart failure. To use information from the MLHFQ in an economic evaluation, the MLHFQ must be mapped onto a preference-based measure of QoL. This study aims to develop a mapping algorithm between the MLHFQ and the Assessment of Quality of Life (AQoL) 8D utility instrument in patients with dilated cardiomyopathy (DCM). Methods MLHFQ and AQoL-8D data were collected on 61 Australian adults with idiopathic DCM or other non-hypertrophic cardiomyopathies. Three statistical methods were used as follows: ordinary least squares (OLS) regression, the robust MM estimator, and the generalised linear models (GLM). Each included a range of explanatory variables. Model performance was assessed using key goodness-of-fit measures, the mean absolute error (MAE), and the root-mean-square error (RMSE). Results The MLHFQ summary score and AQoL-8D utility scores were strongly correlated (r = - 0.83, p < 0.0001) and the two subscales of the MLHFQ were correlated with the eight dimensions of the AQoL-8D. Utility scores were predicted with acceptable precision based on responses to the MLHFQ physical, emotional, social, and other subscales. OLS and GLM performed similarly with MAE and RMSE ranging 0.086-0.106 and 0.114-0.130, respectively. Conclusion The mapping algorithm developed in this study allows the derivation of AQoL-8D utilities from MLHFQ scores for use in cost-effectiveness analyses and most importantly, enables the economic evaluation of alternative heart failure therapy options when only the MLHFQ has been collected.