Emergency department utilization, admissions, and revisits in the United States (New York), Canada (Ontario), and New Zealand: A retrospective cross-sectional analysis

Background:

Emergency department (ED) utilization is a significant concern in manycountries, but few population-based studies have compared ED use. Our objectivewas to compare ED utilization in New York (United States), Ontario (Canada), and NewZealand (NZ).

Methods:

A retrospective cross-sectional analysis of all ED visits between January1, 2016, and September 30, 2017, for adults ≥18 years using data from the StateEmergency Department and Inpatient Databases (New York), the National AmbulatoryCare Reporting System and Discharge Abstract Data (Ontario), and the National Non-Admitted Patient Collection and the National Minimum Data Set (New Zealand).Outcomes included age- and sex-standardized per-capita ED utilization (overall andstratified by neighborhood income), ED disposition, and ED revisit and hospitalizationwithin 30 days of ED discharge.

Results:

There were 10,998,371 ED visits in New York, 8,754,751 in Ontario, and1,547,801 in New Zealand. Patients were older in Ontario (mean age 51.1 years) com-pared to New Zealand (50.3) and New York (48.7). Annual sex- and age-standardizedper-capita ED utilization was higher in Ontario than New York or New Zealand (443.2vs. 404.0 or 248.4 visits per 1000 population/year, respectively). In all countries, EDutilization was highest for residents of the lowest income quintile neighborhoods.The proportion of ED visits resulting in hospitalization was higher in New Zealand(34.5%) compared to New York (20.8%) and Ontario (12.8%). Thirty-day ED revisitswere higher in Ontario (27.0%) than New Zealand (18.6%) or New York (21.4%).

Conclusions:

Patterns of ED utilization differed widely across three high-income coun-tries. These differences highlight the varying approaches that our countries take withrespect to urgent visits, suggest opportunities for shared learning through internationalcomparisons, and raise important questions about optimal approaches for all countries.