Has less traffic, congestion impacted EMS response time during the pandemic?

Changing just one of many variables that impact EMS response to 911 calls points to the complexity of changing average response times


Response time, for better or worse, is a performance standard by which many EMS agencies are measured. Some agencies have contractual obligations to respond to most calls within a certain number of minutes and can be fined for not meeting response time standards.

Getting to the patient quickly is only one piece of the puzzle in a high-quality EMS system. As important, if not more important, is getting the best configuration of responders to the patient in the right amount of time. For example, a sudden cardiac arrest patient needs chest compressions from a layperson or BLS provider before they need paramedics to intubate or push medications.

Lowering response time is more than driving fast, as there are so many variables that can influence the time it takes for an ambulance to reach the patient. Those variables include, but are not limited to:

Response time is an easy metric, with some relation to patient outcome, that is easy to communicate to the public and decision makers.
Response time is an easy metric, with some relation to patient outcome, that is easy to communicate to the public and decision makers. (AP Photo/Ross D. Franklin, File)
  • Starting the clock. In the first year of the EMS Trend Report, one of the top takeaways was that there is a lot of variability in when agencies start the response time clock. Some agencies start the clock when the 911 call is received. Others don’t start the clock until the ambulance clears the station apron and calls enroute to dispatch.
  • Stopping the clock. Another Trend Report takeaway was that EMS doesn’t have a standard as to when the clock stops. Some agencies stop the response time clock when an EMT or paramedic is at the patient’s side, while others stop the clock when they’ve reached the destination, even though the patient might be up three flights of stairs and in the back bedroom of a cramped apartment.
  • Unit availability. The ambulance normally closest to the patient location may already be responding to a call, so the next closest unit responds, which likely extends the response time.
  • Staffing. A service needs to be fully staffed to meet forecasted and actual demand. Being chronically under-staffed is inevitably going to lead to slower response times.
  • Time to return to service. Prolonged patient drop off times because of hospital bed delays and additional ambulance decontamination procedures can reduce the number of units available.
  • Weather. Snow, rain, dust, high winds and more can slow down, rightly so, an EMS response.
  • Traffic and congestion. Freeways and surface streets packed with vehicles can significantly slow the EMS response.
  • Everything else. Cows in the road, a train stalled at the crossing, a running race, a sinkhole and infinite number of other things can slow the EMS response to a 911 call. The world is full of unforeseen circumstances.  

Less vehicles on the road during the pandemic

For decades, EMS systems, leaders and software developers have spent countless funds and resources on system status management, dynamic deployment, computers, vehicles and buildings to position ambulances and their crew members close to the next likely call for service. A stated goal of many of these efforts is to get help to patients faster. Response time is an easy metric, with some relation to patient outcome, that is easy to communicate to the public and decision makers.

The COVID-19 pandemic abruptly sent millions of workers and school children home in March 2020. In many places, once congested roads were suddenly barren and what traffic there was flowed much smoother and faster, sometimes dangerously, than it had pre-pandemic. As the pandemic spans multiple years, millions of Americans are still working from home and not commuting to offices, near or far.

The INRIX 2021 Global Traffic Scorecard shows drops in trips downtown in major urban areas, including Los Angeles (28% decrease), Chicago (21% decrease) and New York (18%) decrease. With fewer vehicles on the road, the average commuter is reaching their destination in less time, with a higher last-mile speed than in previous years. That’s great news for drivers; less time commuting and less money spent on fuel.

Is EMS arriving faster during the pandemic?

Because response time is an important metric in many EMS systems, leaders, regulators and decisionmakers may be curious if EMS is reaping the same benefit of faster travel as commuters to downtown office buildings.

The researchers at ESO crunched the 2020 response time numbers using aggregated data from the ESO Data Collaborative, which is data from more than 2,000 EMS agencies, fire departments and hospitals. The de-identified records from participating agencies inform the ESO COVID-Resource Center, as well as other research projects on EMS trends. Download the “Change in Ambulance Response and Transport Times during the Pandemic” from the ESO Data Collaborative by filling out the form at the end of this article.

Unfortunately, EMS didn’t realize the benefit of less congestion with shorter response times or shorter transport times. Though 911 responses dipped precipitously March to May, 2020, the daily responses by agencies in the ESO Data Collaborative quickly rose and then leveled off for the rest of 2020.

Image used with permission of ESO. 
Image used with permission of ESO.  (Photo/ESO)
Image used with permission of ESO.
Image used with permission of ESO.

The average response time didn’t decline March to June, 2020, the period when most people were under stay-at-home orders and out-of-home trips were at their lowest in many parts of the country. Instead of lower average response time, just the opposite happened. Average response time gradually increased throughout 2020.

Average transport times did dip in April, 2020, potentially corresponding with the dip in 911 responses during the early months of the pandemic. Average transport times, after the April dip, held steady throughout the remainder of 2020.

Image used with permission of ESO.
Image used with permission of ESO. (Photo/ESO)

Verdict: No correlation between traffic congestion and average response

Though your local results may vary, there doesn't appear to be a correlation between less traffic congestion and lower average response time during the pandemic. Nonetheless, it is helpful to pose questions and seek out answers from available data to consider the potential causes of fast or slow ambulance response to a 911 caller. A lot of variables go into the response time equation and changing just one variable, traffic congestion, while not being able to control the other variables, points to the complexity of changing average EMS response time to 911 calls.

Editor's note: Thanks to the agencies who participate in the ESO Data Collaborative for sharing their de-identified data for this analysis. Thanks to the ESO Research scientists for generating the three charts used in this article.

Fill out the form below to download the “Change in Ambulance Response and Transport Times during the Pandemic” from the ESO Data Collaborative. 

ESO's “Change in Ambulance Response and Transport Times during the Pandemic”

By submitting your information, you agree to be contacted by the selected vendor(s) and that the data you submit is exempt from Do Not Sell My Personal Information requests. View our Terms of Service and Privacy Policy.

Recommended for you

Join the discussion

Copyright © 2022 EMS1. All rights reserved.