Non-urgent Visits and Emergency Department Congestion: Patients' Choice and Incentive Mechanisms

A major reason behind crowding in emergency departments (ED) is non-urgent patients' visits to ED. In this paper we investigate how non-urgent ED visits are influenced by patients' imperfect perception of their urgency and their self-interested choice, and we explore interventions that can reduce non-urgent ED visits and social cost. We consider a healthcare setting where heterogeneous patients with imperfect perceptions choose between an expensive/congested ED and less expensive general practitioners (GP) who refer urgent patients to the ED. We model patients' choice problem as a network queueing game, and analytically characterize equilibrium patient flows and their variation with patients' perception errors. We find that non-urgent ED visits and social cost may increase by reducing perception errors. We also characterize socially optimum flows and show that, if optimum flow can be induced at equilibrium then reducing perception errors can guarantee to reduce the social cost. We further explore how to align equilibrium patient flows with optimum flows, and identify scenarios under which perception-improvement measures can achieve this alignment. For other scenarios we design incentive mechanisms to achieve the alignment, which include a novel differential pricing mechanism that leverages the special referral feature of the ED-GP network.