The Effects of Weekday, Season, Federal Holidays, and Severe Weather Conditions on Emergency Department Volume in Montgomery County, Ohio

The purpose of this study was to determine whether day of the week, season, federal holidays, and severe weather conditions affected emergency department (ED) volume in Montgomery County, Ohio. A retrospective analysis of ED visits from July 1, 2010 to July 1, 2011 was conducted. Meteorological data in Montgomery County was obtained from the National Oceanic and Atmospheric Administration (NOAA). A two tailed Analysis of Variance (ANOVA) was used to determine if the total number of ED visits were significantly associated with these variables. The average number of ED visits per day was 722.5. Monday had the highest ED volume (739.5±18.2 visits per day) and Saturday had the lowest number of patients (614.3±18.6 visits per day). Winter saw the highest ED volume (706.3±17.2 visits per day), and fall had the least number of ED visits per day (639.0±18.1). Holidays (p < 0.001), extreme cold temperature (p = 0.0257), and precipitation (p = 0.0071) were associated with a significant decrease in ED patient volume. The day after an extreme cold temperature event had a significant increase in ED volume (p = 0.0320). Strong winds, thunderstorms, tornadoes, floods, and the day after a precipitation event did not have a significant impact on ED volume. ED patient volume is highest on Mondays and during the winter. Extreme cold temperatures and precipitation cause a decrease in ED volume. By using weekday trends and weather forecasts, emergency departments can anticipate patient volume and adjust their staffing and resources accordingly.