International survey on willingness‐to‐pay (WTP) for one additional QALY gained: what is the threshold of cost effectiveness?

Although the threshold of cost effectiveness of medical interventions is thought to be 20 000- 30 000 UK pounds in the UK, and 50 000-100 000 in the US, it is well known that these values are unjustified, due to lack of explicit scientific evidence. We measured willingness-to-pay (WTP) for one additional quality-adjusted life-year gained to determine the threshold of the incremental cost-effectiveness ratio. Our study used the Internet to compare WTP for the additional year of survival in a perfect status of health in Japan, the Republic of Korea (ROK), Taiwan, Australia, the UK, and the US. The research utilized a double-bound dichotomous choice, and analysis by the nonparametric Turnbull method. WTP values were JPY 5 million (Japan), KWN 68 million (ROK), NT 2. 1 million (Taiwan), 23 000 UK pounds (UK), AU 64 000 (Australia), and US 62 000 (US). The discount rates of outcome were estimated at 6. 8% (Japan), 3. 7% (ROK), 1. 6% (Taiwan), 2. 8% (UK), 1. 9% (Australia), and 3. 2% (US). Based on the current study, we suggest new classification of cost-effectiveness plane and methodology for decision making.