We conduct an empirical investigation of the impact of two different queue management systems on throughput times. Using an Emergency Department's (ED) patient-level data (N = 231,081) from 2007 to 2010, we find that patients' lengths of stay (LOS) were longer when physicians were assigned patients under a pooled queuing system, compared to when each physician operated under a dedicated queuing system. The dedicated queuing system resulted in a 10 percent decrease in LOS-a 32-minute reduction in LOS for an average patient of medium severity in this ED. We propose that the dedicated queuing system yielded shorter throughput times because it provided physicians with greater ability and incentive to manage their patients' flow through the ED from arrival to discharge. Consistent with social loafing theory, our analysis shows that patients were treated and discharged at a faster rate in the dedicated queuing system than in the pooled queuing system. We conduct additional analyses to rule out alternate explanations, such as stinting on care and decreased quality of care. Our paper has implications for health care organizations and others seeking to reduce throughput time, resource utilization, and costs.Key words: pooling, queue management, strategic servers, social loafing, empirical operations, health care 3
IntroductionImproving efficiency and customer experience are key objectives for managers of service organizations.Skillful application of operations management principles may prove helpful for achieving these goals. In this paper, we investigate queue management, a key operational decision. More specifically, we explore the impact on throughput time of using a pooled queuing system or a dedicated queuing system.Prior work on queue management has demonstrated through analytical models that pooling separate streams of identical customers into a single queue served by a bank of identical servers leads to a reduction in waiting time and an increase in server utilization (Eppen 1979, Kleinrock 1976. This occurs because pooling reduces the negative impact of variability in arrival times and processing times. Pooling enables incoming work to be processed by any one server from a bank of servers, which decreases the odds that an incoming unit of work will have to wait for service. This situation compares to the one where the unit of work can only be processed by a single dedicated server.Queuing theorists have advanced this stream of research by identifying conditions under which queue pooling may not yield the expected performance improvements (Debo et al. 2008, van Dijk and van der Sluis 2009, Hopp et al. 2007, Jouini et al. 2008, Loch 1998, Mandelbaum and Reiman 1998. However, few empirical studies have examined the performance of pooled versus dedicated queuing systems. This is an important omission because, in practice, employees can often make adjustments to how they manage their work system to achieve a goal, such as increasing their productivity (Hopp et al. 2009). Operations management scholars advocat...