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ESO Data Collaborative.

Expanding the evidence base with data from more than 2,700 organizations

The ESO Data Collaborative consists only of entities that have voluntarily agreed to allow use of their de-identified records for research and benchmarking purposes. In 2022, the Collaborative included data from over 2,700 EMS agencies, fire departments, and hospitals.


Annual Research Dataset

Built from the ESO Data Collaborative for research use and is made available in the second quarter of the following year.


Access to the Research Dataset

Access to this dataset is provided following a research proposal process and review from the Research Leadership Group.


ESO Data Collaborative Research Projects

The ESO Data Collaborative has powered more than 70 research projects.

Icon representing the Annual Public Use Research Dataset.

Annual Public Use Research Dataset

Each year, a standardized core dataset is built from the ESO Data Collaborative for research use and is made available in the second quarter of the following year. Access to this dataset is provided following a research proposal process and review from the Research Leadership Group.

Map of the United States of America.

Over 12 million encounters in the dataset

The 2022 ESO Data Collaborative public release research dataset contains 12,803,154 EMS encounters (86% represent 911 responses) from 2,705 agencies. The majority of included EMS responses occurred in the South (51%) US Census region, followed by the Midwest (24%), West (17%) and Northeast (8%). Based on the CMS urban city categorizations, most encounters occurred in urbanized areas (80%).



Laptop screenshot of ESO EMS HDE Patient Outcomes feature.

Linking hospital outcome info with HDE

Approximately, 20% of records with EMS emergency response and patient transport had linked hospital outcome information through the HDE software, with representation from 26% of all agencies participating in the Data Collaborative.

Screenshots of three ESO research studies displaying graphs and charts.

More than 70 research projects

The ESO Data Collaborative has powered more than 70 research projects, including award-winning presentations at national conferences and peer-reviewed manuscripts in journals like Prehospital Emergency Care, Annals of Emergency Medicine, Resuscitation, and Journal of the American College of Emergency Physicians Open.

Pain Management Annals 602x350

Pain Management Annual Report

Using the 2019-2020 ESO Data Collaborative, this study examines out-of-hospital analgesic administration among emergency medical services (EMS) records for 9-1-1 advanced life support transport of adult patients diagnosed with long bone fractures. All patients were diagnosed with long bone fractures (humerus, radius/ulna, femur, or tibia/fibula) at the emergency department, resulting in a total of 35,711 records between January 1, 2019, and December 31, 2020 included in this analysis. This hospital outcome data was directly linked to the EMS records through ESO’s Health Data Exchange software.  Analgesic administration primarily rests within the control and discretion of attending EMS clinicians. The researchers found that EMS administered pain medication to 72% of White patients with severe pain compared to just 59% of Black patients with severe pain. These disparities were not explained by differences in clinical presentations, patient preferences, or community socioeconomic conditions.

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Three pages of an ESO research on the role of sodium bicarbonate (bicarb) in cardiac arrest.

Sodium bicarbonate administration is associated with improved survival in asystolic and PEA Out-of-Hospital cardiac arrest

The role of sodium bicarbonate (bicarb) in cardiac arrest has long been a controversial topic with limited evidence. The latest guidance from the American Heart Association does not support routine use of bicarb in cardiac arrest, but could there still be a time and a place for this medication? Like the answer to many questions – it probably depends.

A recent study published in Resuscitation used data from more than 1,300 EMS agencies in the ESO Data Collaborative to dig deeper into the effects of bicarb use in cardiac arrest. The study used the ESO Data Collaborative to analyze electronic health records from more than 1,300 agencies between 2019-2020. The Researchers considered cases of patients with cardiac arrest and resuscitations that lasted 5–40 minutes. They stratified the analysis based on presenting electrocardiogram (ECG) rhythms: ventricular fibrillation or ventricular tachycardia (VF/VT), pulseless electrical activity (PEA), or asystole.

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Cover of Ketamine research paper.

Out of Hospital Ketamine Indications for Use, Patient Outcomes, and Associated Mortality

The objective of this study was to describe prehospital ketamine use, patient outcomes, and the potential contribution of ketamine to patient death. In this sample of more than 11,000 patients across the U.S. who received prehospital ketamine, the most common indication was for trauma/pain (49%, 5,575), followed by altered mental status/behavioral (34%, 3,795), cardiovascular/pulmonary (13%, 1,454), seizure (2%, 248), and other indications (2%, 219). Doses observed fell within accepted therapeutic ranges and nearly all patients were transported to a hospital. Ketamine could not be ruled out as a contributing factor in 2 on scene deaths (0.02% of exposures) and 6 hospital deaths (0.3% of exposures). Following ketamine administration, hypoxia and hypercapnia were documented in 8.4% (897) and 17.2% (1,311) of patients, highlighting the importance of continuous SpO2 and EtCO2 monitoring.

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Interior page of an ESO Bibliography.

Access to the entire bibliography

View the entire bibliography of ESO Data Collaborative powered works and request reprints.

ESO Research Leadership Group.

ESO Research Leadership Group Volunteers

The use of the data from the Data Collaborative is governed by the ESO Research Leadership Group (RLG).  The RLG is comprised of volunteers who are leaders in the industry and are charged with evaluation of requests for utilization of the Collaborative to assure the data are sufficient to answer the intended question as well as to assure appropriate constraints regarding commercial bias and potential conflicts of interest.

All members are serving as individuals and are not representing any organization.

  • Amy Hanifan BS
  • Elizabeth Donnelly PhD
  • Henry Wang MD
  • Jason Moats PhD
  • Jeff Jarvis MD
  • Joelle Donofrio-Ödmann MD
  • Jonathan Stallings, PhD
  • Kate Remick MD
  • Lawrence Brown PhD
  • Robin Garza RN
  • Jon Kromer MD
  • Rick Verbeek MD


Frequently Asked Questions

Is there a cost for the ESO Data Collaborative Research Dataset?

There is no cost for the standard annual research dataset.

How do I get access to the ESO Data Collaborative Research Dataset?

Access to the standard annual research dataset is provided following submission of a research proposal and approval from the Research Leadership Group. Fill out the data request form to get started.

If I need help with my research project, does ESO provide assistance? 

Yes, we have a limited ability to assist with external research projects. Please email [email protected] for further details.

How can my agency join the ESO Data Collaborative?

A member of leadership from your organization can complete request form at the bottom of this page.  We will take it from there.

Submit a Request to the Research Team

Fill out the form below to request data from our research team or reprints of a publication.