Fig. 4

Cost Effectiveness Acceptability Curve. This graph plots the probability that IDM is cost-effective in comparison to UC for a variety of scenarios. The x-axis is a continuous willingness to pay threshold (WTP) in Canadian dollars. The y-axis represents the probability that IDM is cost-effective. The vertical grey-dotted line reflects a WTP of $50,000 per QALY. 1 Year Trial-Analysis (1.5% Discount): Reflects the one-year trial analysis with a starting age of 68 with a discount rate of 1.5% per annum. 10 Year Simulation (1.5% Discount): Reflects the model-based analysis if run for 10 years (i.e., 60–70 years of age) with a discount rate of 1.5% per annum. 20 Year Simulation (1.5% Discount): Reflects the model-based analysis if run for 20 years starting at 68 years (i.e., 68–88 years of age) with a discount rate of 1.5% per annum. 5 Year Simulation (1.5% Discount): Reflects the model-based analysis if run for 5 years (i.e., 60–65 years of age) with a discount rate of 1.5% per annum. Base Case (1.5% Discount): Reflects the base case scenario for the model-based analysis if run for 30 years (i.e., 60–90 years of age) with a discount rate of 1.5% per annum. Double Treatment Cost (1.5% Discount): Doubling the cost of all elements associated with the treatment in the IDM group with a discount rate of 1.5% per annum. IDM EQ-5D >  = UC EQ-5D (1.5% Discount): Assumes that the utility attributable to the IDM group are always greater than or equal to the utility in the UC group with a discount rate of 1.5% per annum. This reflects the assumption that embedding a CRE within a primary care setting should not negatively impact a patient’s quality of life. Ten Thousand Simulations (1.5% Discount): Explores the stability in the estimates of “Base Case (1.5% Discount)” based on 10,000 replications.