Fig. 4. C/D, I/D, and I/S definitions.

For a time-dependent ROC analysis at time t, C/D defines patients a and b, who encountered the event between time zero and time t as cases, and patients c and d, who were event-free at time t as controls. I/D defines patient b, who had the event at time t, as a case, and patients c and d, who were event-free at time t, as controls. I/S defines patient b, who had the event at time t as a case, and patient d, who was event-free at time t and until a pre-specified fixed time (denoted as t^*), as controls. C/D = cumulative/dynamic, I/D = incident/dynamic, I/S = incident/static, ROC = receiver operating characteristic