Simulation-based analysis of scheduling decisions in an outpatient clinic

In an outpatient clinic, in which multiple classes of patients are given appointments, capacity management and scheduling decisions are particularly important. Once an appointment is scheduled; it is not uncommon for the appointment to be rescheduled or cancelled prior to the appointment day, or a patient may simply not show-up on his/her appointment day. Thus it is crucial to consider all of these patient behaviors when assigning an appointment. In this study we consider multiple classes of patients with different demand rates, service times, and different delay-dependent reschedule, cancellation, and no-show rates. We develop a simulation model to analyze the effects of reducing the appointment planning horizon. In our experimental analysis we also evaluate different calendar structures: traditional slots, standardized 20 or 30 minute slots, and slotless designs. We use capacity utilization and "seen" patient proportions as the performance indicators in our model. Our results indicate that we can significantly increase physician utilizations and the percentage of seen patients by reducing the appointment planning horizon. We also observe improvements in the performance indicators if we use a slotless design or standardized appointments with shorter slot lengths.