Quality of life and time to death: have the health gains of preventive interventions been underestimated?
This article explores the implications of the relation between quality of life (QoL) and time to death (TTD) for economic evaluations of preventive interventions. By using health survey data on QoL for the general Dutch population linked to the mortality registry, we quantify the magnitude of this relationship. For addressing specific features of the nonstandard QoL distribution such as boundness, skewness, and heteroscedasticity, we modeled QoL using a generalized additive model for location, scale, and shape (GAMLSS) with a β inflated outcome distribution. Our empirical results indicate that QoL decreases when approaching death, suggesting that there is a strong relationship between TTD and QoL. Predictions of different regression models revealed that ignoring this relationship results in an underestimation of the quality-adjusted life year (QALY) gains for preventive interventions. The underestimation ranged between 3% and 7% and depended on age, the number of years gained from the intervention, and the discount rate used.
['Gheorghe|Maria|M|', 'Brouwer|Werner B F|WB|', 'van Baal|Pieter H M|PH|']
D000367:Age Factors D000368:Aged D000369:Aged, 80 and over D001294:Attitude to Health D003362:Cost-Benefit Analysis D003643:Death D005260:Female D006801:Humans D008297:Male D008875:Middle Aged D008962:Models, Theoretical D009426:Netherlands D017063:Outcome Assessment, Health Care D011788:Quality of Life D019057:Quality-Adjusted Life Years D012737:Sex Factors D013997:Time Factors
quality of life time to death prevention GAMLSS QALYs β inflated distribution