The state transition diagram of our MDP model shows transitions between various stages depending on the decision made.

<p>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 (<i>BX</i>), or annual mammography (<i>AM</i>). If biopsy is elected, the patient will then move to either the malignant biopsy state (Biopsy-M) or the benign biopsy state (Biopsy-B).