Fig. 3

Impact of the willingness-to-pay threshold on the sample size power function curve, at the correlation coefficient observed in the respective trial

Legend: Panels a), b), and c) were examined based on the hypothesis test: \({H}_{0}:\hspace{0.25em}b\left(\lambda \right)\le 0\), versus \({H}_{1}:b\left(\lambda \right)>0\). Panels d) and e) were examined based on the hypothesis test \({H}_{0}:\hspace{0.25em}b\left(\lambda \right)\ge 0\), versus \({H}_{1}:b\left(\lambda \right)<0\)