Fig. 1
A unidirectional illness-death model for VTE and recurrence in patients with localized CRC after surgery. The transition hazards for the respective transitions between the states are labeled as αxy(t), respectively. In this three-state, three-transition unidirectional illness-death model, the states 1, 2, and 3 represent an initial, transient, and absorbing state, respectively. In state#1, patients are alive and free from recurrence and VTE after curative surgery. They can either remain in this “initial” state, transit into the “intermediate” state#2 (transition#1), or transit into the “absorbing” state#3 (“recurrence”) either directly from state#1 (transition#2) or from state#2