Outpatient appointment scheduling with urgent clients in a dynamic, multi-period environment

Time waiting for service is a major concern for consumers, and excessive waiting for a pre-scheduled appointment is especially annoying. This is an on-going problem because appointment scheduling is a challenging task, mainly due to the uncertainties associated with service times. Prior studies have focused mainly on a single scheduling period (i.e. either a morning or afternoon); this paper uses a more realistic model that represents an on-going, multi-period scheduling environment where clients can be scheduled days or even weeks into the future. Two main objectives will be considered; the best scheduling rule to use in a multi-period environment, and the best placement of appointment slots that are left open for urgent clients. Both of these have been studied in a single period environment, and results here will be compared to those. It will be shown that in some cases earlier findings from the one-period environment are robust and perform well in a multi-period environment, while in other cases the one-period findings do not apply.