Fig. 4

Cost-effectiveness acceptability curve in the DTx + TAU and TAU-only groups. The X-axis indicates the threshold value for 1 QALY gained (we preset the threshold value as ¥5 million/QALY gained, shown as the dashed line), and the Y-axis denotes the probability of being chosen as the most cost-effective option. As the threshold value increases, the probability of choosing the DTx + TAU strategy (the blue curve) sharply increases, whereas that of choosing the TAU-only strategy (the red curve) decreases. At the intersection of the two curves, the threshold value was approximately ¥1,200,000/QALY gained, which was sufficiently below the preset threshold of ¥5 million/QALY gained. Abbreviations: DTx digital therapeutics, JPY Japanese yen, QALY quality-adjusted life years, TAU treatment as usual