Patient Sensitivity to Emergency Department Waiting Time Announcements

Abstract

Emergency department (ED) delay announcement systems are implemented in many countries. We answer three important questions pertaining to the operations and effectiveness of such systems in the case of Hong Kong SAR: (1) How many patients are aware of (and sensitive to) the ED waiting time announcement system? (2) How sensitive are these patients to the announced waiting time? (3) How can we improve the waiting time announcement system? We study how customers (patients) respond to delay announcements in a network of service providers where customers can decide which to join. We estimate the tradeoff in the patient's ED choice decision of weighing the travel distance to an ED and the time waiting at the ED. By studying the Hong Kong public hospital network and ED waiting time announcement system, we provide suggestions for enhancing the system's effectiveness. We study over 1.3 million patient visits to 17 public hospitals over a calendar year. Using a latent class conditional logit model, we estimate the fraction of patients sensitive to the announced waiting time and their sensitivity to the announcements as well as patient characteristics that lead to higher sensitivity. We simulate the operation of the three EDs on Hong Kong Island for counterfactual policy study. We find that 0.8%, 3.1%, and 4.8% of triage level 3, 4, and 5 patients (2.5% overall) are sensitive to the announced waiting time, and are willing to travel an additional 12.3, 4.6, and 3.5 km (6.8 km overall) to save one hour of waiting, respectively. In addition, we show that patients over 60 years old and those residing in the area of Kowloon are much less likely to be sensitive to the announcement system. Our counterfactual analysis shows, for example, that the average waiting time and number of left without being seen (LWBS) patients among the three Hong Kong Island EDs can be reduced by 1.4% and 11.5%, respectively, by increasing the awareness (fraction of sensitive patients) to 15.8% and, simultaneously, reducing the announced waiting time update window to 1 hour from the current level of 3 hours. Our results also show that at the current 3-hour level of update delay, increasing awareness above 40% is detrimental to the system, as it leads to increases in the average ED waiting time and the number of LWBS patients. Urgent patients are less likely to be sensitive to the delay announcement than less urgent patients but those that are sensitive are more waiting time-averse than their less urgent counterparts. The Hong Kong government should focus on the older population and Kowloon district in promoting the ED waiting time announcement system. At the same time, improving awareness beyond a certain level without providing the most recent delay information may actually worsen the system performance due to “oscillating effect” among EDs. Note: Funding Information: Hong Kong Research Grants Council, General Research Fund (GRF) No. 17502320, “Impact of emergency department waiting time announcements on patient behavior” Declaration of Interests: None to declare. Keywords: delay announcement, queueing behavior, queueing network coordination, emergency department, cost of waiting