Comparison of Two Scheduling Systems

Abstract

The delays that outpatients have to undergo before getting their medical treatment are often excessively long. The most commonly used patterns of scheduling appointments to patients are classified into three categories: (1) Pure Block Appointment systems, (2) Individual Appointment Systems, and (3) Mixed Block-Individual Appointment Systems. Several analytical studies have been concerned with the comparison of some of these appointment systems, and their highlights are described briefly. There are many other possible ways of assigning appointments to patients; one such way, referred to as the Two-at-a-Time Appointment System, is described. The advantages of the Two-at-a-Time Appointment System over any of the commonly used ones are discussed. Finally, the steady-state waiting time distribution functions that will correspond to the Two-at-a-Time Appointment System and the Individual Appointment System, as applied to the Wilmer Outpatient Clinic, have been obtained and are compared.

A simulation study of outpatient scheduling with multiple providers and a single device

“…Combining these attributes leads to a variety of appointment systems, as shown in Table 4. [6] Mercer (1973) [7] Soriano (1966) [8] Fries & Marathe (1981) [9] Liao et al (1993) [10] Liu & Liu (1998b) [11] Liu & Liu (1998b) [11] Mahacheck & Knabe (1984) [12] Bailey (1952) [13] Welch & Bailey (1952) [14] O'Keefe (1985) [15] No-shows (Noshow Probability) [16] Liu & Liu (1998b) [11] White & Pike (1964) [17] Walk-ins [17] Fetter & Thompson (1966) [16] Queue Discipline FCFS 1 st priority given to emergencies or patients returning from X-ray, etc. ; 2 nd scheduled patients and 3 rd walk-ins.…”

Optimal Allocation of Surgery Blocks to Operating Rooms Under Uncertainty

“…On the other hand, Wang (1993) discusses the problem in a manufacturing setting where the objective is to schedule the arrival of parts on the shop floor such that work-inprocess inventory and machine idling are minimized. There have been numerous other simulation and queuing-based studies presented in operations research, statistics, and health care journals over the past several decades on the problem of assigning start time for surgeries and outpatient clinic appointments (for example Bailey (1952), Charnetski (1984), Dexter et al (1999), Ho and Lau (1992), Jansson (1966), Mercer (1973), Rohleder and Klassen (2002), Soriano (1966), Welch (1964), and references therein). Ho and Lau (1992) used Monte-Carlo simulation to compare the performance of many of the proposed scheduling heuristics.…”

A new appointment rule for a single-server, multiple-customer service system

“…While Bailey [1,2] examined a rule that assigns individual appointment times, Blanco White and Pike [3], Fries and Marathe [8], and Soriano [18] examined the block appointment rules. Using computer simulation, Blanco White and Pike [3] recommended an appointment rule comprised of appointment blocks of one tenth the average length of a service session, a fixed number of customers per block equals to the service rate, and a server's arrival time of less than 5 min after the first appointment.…”

“…Using computer simulation, Blanco White and Pike [3] recommended an appointment rule comprised of appointment blocks of one tenth the average length of a service session, a fixed number of customers per block equals to the service rate, and a server's arrival time of less than 5 min after the first appointment. Using analytical procedures, Fries and Marathe [8] proposed appointment blocks of variable block size while Soriano [18] proposed scheduling two customers in each constant block size of two times the average service time.…”

“…First, many of the results were tested and valid only for specific service environments. Second, researchers such as Soriano [18] and Fries and Marathe [8] unrealistically assumed exponential service times to facilitate the use of their analytical procedures. Third, most studies had not rigorously tested their appointment rules in different service environments.…”