Table 1.
BI-RADS final assessment codes with recommendations.
Figure 1.
The state transition diagram of our MDP model shows transitions between various stages depending on the decision made.
Nodes represent the state of the model and arcs represent the transition of patient from one state to another. Round nodes in the first column represent the risk-score-states consisting or probability of cancer (e.g. 1%, 2%, …, 100%) of the patient of age 40. Round nodes in the second column represent the risk after 1 year. At each decision epoch, depending on the risk of cancer, the radiologist needs to make one of the two decisions–biopsy (BX), or annual mammography (AM). If biopsy is elected, the patient will then move to either the malignant biopsy state (Biopsy-M) or the benign biopsy state (Biopsy-B).
Table 2.
Variable Definitions with Sensitivity Analysis Ranges.
Figure 2.
Disutility factors used in sensitivity analysis.
Figure 3.
Optimal biopsy threshold (base case model).
Note: In our MDP, we consider age 99 as the last year that a decision is made and we assign a terminal reward (i.e. expected life) at age 100 irrespective of the action taken. For this reason, optimal threshold calculations for Figures 3–7 end with age 99.
Figure 4.
Sensitivity of the optimal biopsy threshold as disutility at age 40 varies.
Figure 5.
Sensitivity of the optimal biopsy threshold as the disutility factor varies.
Figure 6.
Sensitivity of the optimal biopsy threshold as the fraction of invasive cancers varies.
Figure 7.
Sensitivity of the optimal biopsy threshold as the treatment effectiveness factor varies.