Local EMS Services State EMS Officials

NEMSIS Version 3
Resources for
local EMS Services


Getting Started


When it comes to EMS, one size definitely doesn’t fit all. But there are many similarities between implementing NEMSIS Version 3 in a fire department and implementing NEMSIS Version 3 in a private ambulance service, third-service EMS agency or volunteer ambulance service. For example, asking members of your workforce to change the way they report data may sound daunting. But the benefits of moving to NEMSIS Version 3 far outweigh the challenges of implementing a new reporting tool. And with the right preparation, your EMS service, regardless of its type, can ensure a smooth transition to NEMSIS Version 3 in compliance with your state’s reporting requirements.

The keys to a smooth upgrade to NEMSIS Version 3 are preparation and communication. Here are some essential tips:

  • Ensure that field providers are aware of the coming changes — and properly trained prior to implementation.
  • Communicate early and often with internal IT staff, state EMS officials, data managers and your software vendor.
  • Ensure that any required hardware upgrades are addressed early on.

FAQs About NEMSIS 3 for Leaders of Local EMS Services



The National EMS Information System (NEMSIS) is an EMS industry data standard that allows a uniform method of collecting information related to EMS patient care and operations. NEMSIS defines data fields for electronic patient care reports (ePCRs) so that a paramedic treating a patient in Ohio is collecting data in the same way as an EMT in Arizona, even if they are using different ePCR or electronic health record (EHR) software.

Version 3 is the latest NEMSIS standard. It’s currently being implemented by states and territories across the United States. (While there are currently two separate fielded standards, 3.3.4 and 3.4.0, they are very similar and commonly referenced together as Version 3.) NEMSIS Version 3 offers many opportunities not available with previous versions, such as:

  • More specific fields in order to collect data that can help EMS systems measure and improve performance, as well as provide necessary information to hospitals and other healthcare entities involved in care for the patient
  • Improved validation system to help ensure that patient reports submitted to the state by local agencies have the required minimum information for a complete record
  • A web-based submission system that allows for easier, real-time submission to state and national EMS databases
  • Ability to integrate with other healthcare records through use of the Health Level 7 (HL7) standard

Moving to NEMSIS Version 3 will also help state and local EMS systems in other ways — for example, improving the ability to research and develop evidence-based protocols for patient care, and preparing EMS systems for future changes to reimbursement models. The EMS Compass initiative, designed to create standardized performance measures, uses the Version 3 standard; agencies using Version 3 data will be able to use these evidence-based measures to measure and improve patient care.

Other features of NEMSIS Version 3 include:

  • Use of ICD-10 codes for impressions, signs and symptoms, injuries and locations.
  • Use of SNOMED codes for procedures and environment allergies.
  • Use of RxNORM codes for medications and allergies.
  • Documentation of pertinent negatives.

NEMSIS Version 3 uses ICD-10 codes for documenting the provider impression of the patient’s chief reason for requesting and requiring EMS treatment or transport. ICD-10 is the latest edition of an international classification system used by most hospitals, healthcare providers and payers in the United States to document provider’s impressions and diagnoses. This expanded list now allows your EMTs and paramedics to document their impression of a patient's condition at a much deeper level than previously allowed, but also still allows for less-detailed descriptions by using a hierarchical coding system. For example, for every detailed code (e.g., “turtle bite”) there is a base code (“animal bite”) that is less specific.

Several of the "questions" in NEMSIS Version 3 appear rather similar but are different in clinically important ways. A common example is being able to document the exact same item in the “Primary Impression” field as in the “Primary Symptoms” field. While these questions might allow for some of the same answers on certain occasions, they also allow for much more detail, as the symptoms can help build a case to justify the impression that was entered.

The NEMSIS V3 data dictionary consists of 574 data elements, which were developed with input from stakeholders across the country. While these elements capture all of the information needed during a typical EMS encounter with a patient today, states also have the option of adding additional data fields for research or as new data collection needs are discovered. As states develop these customized fields, NEMSIS works to ensure they are shared with other states and with software vendors so other states can adopt the same elements if they desire. The custom elements shared with NEMSIS are available on the NEMSIS website.

While NEMSIS is a national standard, EMS is regulated at the state and/or local level—meaning it is ultimately up to states and localities to decide exactly what data elements to collect and how to collect them. For this reason, it is vitally important to know what your state’s plan is for NEMSIS v3 implementation.

The first step is to ensure that you are using software that is compliant with NEMSIS Version 3 and standards required by your state and/or local jurisdiction. A list of vendors recognized by the NEMSIS Technical Assistance Center (TAC) is available here. To verify that a vendor is compliant with state and local regulations, contact your state and local EMS officials. (Contact information for state EMS data managers is also available here.)

After collecting data during patient encounters, local EMS organizations typically are responsible for submitting that data to state databases in the NEMSIS format via a web service, which allows information to be exchanged securely, even across different operating systems and programming languages. Unlike with previous versions of NEMSIS, Version 3 allows for automated, near real-time submission of data. That also means that states and local agencies will get faster feedback on the quality of the data, making it easier for information to be corrected sooner and more accurately.

Many EMS software vendors perform this function on behalf of their customers; some require customers to submit data on their own. Early in the transition to Version 3, make sure you are in contact with your vendor and state officials to ensure you are prepared to submit data in a timely manner—many states have rules and regulations that require data submission, with fines or other penalties for agencies that do not comply.

This is a question for your software vendor. Some agencies will be able to transfer data into a new system, allowing for seamless integration and the ability to trend over time across the period of the transition. Others will find that the upgrade will require maintaining a separate database for information collected prior to the transition. Either way, it is critical to ensure that the data is not lost in order to still have access to it for planning, performance measurement, long-term recordkeeping, and other uses.

NEMSIS Version 3 ensures better data quality using a dual-pass validation system. The first pass is XML validation, which ensures the data is properly formatted—for example, making sure the dispatch date is not only present, but includes a four-digit year. The second pass is something called Schematron — a rule-based language for XML document validation that is capable of logical comparison for business rule validation. For example, Schematron may ensure that the date of transport to the hospital is not prior to the dispatch date, since you cannot transport a patient prior to being dispatched.

Data quality is also ensured through compliance testing of software used at both the state and local levels.

Incremental changes are made to the NEMSIS data standard every two to four years, while critical patches may be published more frequently. Updates to the NEMSIS Version 3 dataset are announced and posted on the NEMSIS TAC Website. You can also subscribe to the NEMSIS List Server, or join the discussion group, to be informed via email on important facts and news. Many state EMS offices also hold regular webinars and conference calls, publish newsletters or emails, and have websites with more information. Check with your state EMS office or on nemsis.org for links and contact information.

Your service will need to use patient care reporting software that is compliant in each state in which it operates. If the states require different elements, your organization will need to work with your software vendor and state EMS officials to ensure the right data is being collected and submitted to each state in order to comply with regulations.

A special challenge arises if your service operates simultaneously in one state that uses the NEMSIS 2 standard and another that uses NEMSIS 3. In that case, ask your software vendor about mapping data from NEMSIS 3 down to the more general NEMSIS 2 dataset, a process known as a “downgrade cross walk.” An alternate arrangement may be to maintain separate accounts with a software vendor. In either case, this question underscores the importance of good communication and starting the process well in advance of your state’s deadline.

There are minor differences between the versions. Version 3.4 introduces a few new fields, eliminates some, and modifies a few others.

The NEMSIS TAC will collect both NEMSIS Version 3.3.4 and Version 3.4 data until the end of 2017; Version 3.4 will officially become the standard on January 1, 2018. Major revisions to the NEMSIS standard will occur on a four-year cycle. The next major revision could be released in March 2018 and would officially become the standard on January 1, 2019.

After most states collect data from local agencies, they submit a subset of that data to the National EMS Database. Because each state collects EMS data using the same standards, the tens of millions of de-identified patient care records in the national database can be used by researchers and policymakers to answer questions about EMS systems and patient care delivery.

Back to Top

NEMSIS 3 Implementation Checklist for EMS Services



Following is a checklist that any state or territory EMS data manager can use to ensure the transition to collecting NEMSIS Version 3 data proceeds easily with no surprises.



Field Personnel



For local EMS services implementing NEMSIS Version 3, ensuring that paramedics and EMTs know the reason for the changes, along with the value that the new standard brings, is key to adoption and a successful transition. This FAQ was designed to help EMS providers understand the transition to Version 3 and how it may impact them and their patients.


The National EMS Information System (NEMSIS) is an EMS industry data standard that allows a uniform method of collecting information related to EMS patient care and operations. NEMSIS defines data fields for electronic patient care reports (PCRs) so that a paramedic treating a patient in Ohio is collecting data in the same way as an EMT in Arizona, even if they are using different ePCR or electronic health record (EHR) software.

Version 3 is the most recent NEMSIS standard. It’s currently being implemented by states and territories across the United States. Your EMS service may be upgrading because your state has mandated that all EMS calls be documented using Version 3. Or perhaps your EMS service’s leaders wish to improve their ability to use data to improve patient care.

Version 3 offers many opportunities that were not available with earlier versions of NEMSIS, such as:

  • More specific number of data fields in order to collect the data that can help EMS systems measure and improve performance and provide necessary information to hospitals and other healthcare entities involved in care for the patient. For example, NEMSIS 3 has added pertinent negatives, so you can document why a chest pain patient did not receive aspirin.
  • Improved validation system to help ensure that the patient reports your agency submits to the state have the required minimum information for a complete record
  • A web-based submission system that allows for easier, real-time submission to state and national EMS databases
  • Ability to integrate with other healthcare records through use of the Health Level 7 (HL7) standard
  • Moving to NEMSIS Version 3 will also help your state and the local EMS system(s) you work for in other ways. For example, Version 3 will make it easier to research and develop evidence-based protocols for patient care. The new standard will also help EMS systems measure performance and quality. The EMS Compass initiative, designed to create standardized performance measures, uses the Version 3 standard; agencies using Version 3 data will be able to use these evidence-based measures to measure and improve patient care.

The changes in NEMSIS Version 3 will not directly change how you perform your job in the field treating patients but they will improve how you document the care provided. NEMSIS 3 does not, for example, dictate your treatment protocols or regulate your certification or licensing. That said, the answer to this question varies on how your employer implements the new standard, particularly when it comes to software. In many organizations that are already using electronic PCRs, the move to NEMSIS 3 will mean the addition of some new data fields and changes in the options to complete some data fields that already existed—but the PCR itself will not change significantly.

In other services, a change in PCR software may be required as some software vendors have not developed a Version 3 compliant product. If you practice EMS in such an organization, you may have to learn new software—but because NEMSIS has standardized the data collected by EMS providers across the country, the information you enter into the report should be similar to what you were entering with previous software.

One of the most significant changes in Version 3 is that the Provider Impression field is now based on patient diagnoses that are linked behind the scenes to the same ICD-10 codes used by physicians. ICD-10 is the latest edition of an international classification system used by most hospitals, healthcare providers and payers in the United States to document providers’ impressions and diagnoses. Using ICD-10 codes will help create consistency between EMS and the rest of the healthcare system. But it also may mean a change in what options are available for you when you document the provider impression. Follow your service’s policies and your state’s instructions for how best to complete this field.

Several of the questions in NEMSIS Version 3 appear repetitive at first glance, but are different in clinically important ways. A common example is being able to document the exact same item in the Primary Impression field as in the Primary Symptoms field. While these questions might be answered the same way under certain circumstances, they also provide much more detail, as the symptoms can help build a case to justify the impression that you enter.

There are several reasons for variations among patient documentation software systems in EMS. One is simply that agencies can choose which software platform best meets their needs, as long as it complies with local and state requirements.

In addition, while NEMSIS establishes a baseline set of data to be collected, EMS is regulated at the state and/or local level—meaning it is ultimately up to states and localities to decide exactly what data elements to collect and how to collect them. The NEMSIS Version 3 data dictionary consists of 574 data elements, which were developed with input from stakeholders across the country. While these elements capture all of the information needed during a typical EMS encounter with a patient, states also have the option of adding additional data fields for research or as new data collection needs are discovered.

The simple answer is that the information you document is used by the hospital, your service, and at state and national levels to improve patient care. At the individual level, the hospital can look at your patient care report to find information about the patient you transported and what treatments or actions you may have performed. NEMSIS Version 3 uses the HL7 standard used by many hospital systems, which means patients’ EMS records can be merged more easily with those from the hospital.

At the local level, your EMS service can use the data to help assess the local EMS system’s or community’s needs. For example, your service might want to know whether there’s been a rise in opioid use in a certain area, so it can work with public health and law enforcement to help prevent overdose deaths. Or your quality improvement manager might look at whether practitioners are checking blood sugars on appropriate patients. The data can also be used locally to increase protocol compliance or modify protocols to align with what actually happens in the field and patient outcomes.

Information entered into the ePCR using NEMSIS Version 3 is also then submitted to the state and eventually the National EMS Database. This data is used not to look at an individual patient’s information for treatment purposes, but to provide regulators, policy makers and researchers a way to assess EMS system performance across larger geographical areas. For example, a study might use Version 3 data at the national level to help determine which EMS treatments make the most difference for patients.

Back to Top

Need a full downloadable version?



Get the exclusive downloadable version of this Toolkit today in convenient eBook format. Brought to you by ESO.