FIGURE 1.

A, Transition states for stochastic microsimulation of patients on IFX. The probability of transition to a flare was dependent on presence of a flare at prior time step, current IFX concentration, and the presence of anti-IFX antibodies. If a flare did not resolve over 2 time steps (16 weeks) without further medical escalation, the patient was transitioned off IFX to adalimumab. B, Transition states for progression of medical and surgical therapy following IFX. If subjects had an initial response, they progressed to maintenance of response. If there was no induction response, they proceeded to the subsequent medical induction. Post-surgical states were terminal states. Surgical complication included death and immediate and prolonged surgical complications.