Before the Ambulance Arrives: What Dispatch Data Is Starting to Show Us

By Brent Myers, MD, MPH, FACEP, FAEMS

The bipartisan CARE Act, introduced last November, would create the first Medicare pilot program for reimbursing EMS agencies that treat patients on scene rather than defaulting to emergency department transport. It builds on findings from the ET3 model, which post-hoc evaluation found averaged $512 in Medicare spending per treatment-in-place encounter on a same-day basis, representing significant savings potential compared to low-acuity ED visits. According to the bill’s sponsors, about 22% of EMS calls already conclude without transport, costs that providers absorb under current reimbursement models.

The policy direction is clear but making it actionable requires knowing which calls can be safely managed without transport, a determination that starts with the dispatch decision and the evidence base now emerging around it.

What the Dispatch Decision Actually Controls

The dispatcher is the first medical contact in the emergency care chain. Their categorization shapes what the responding crew expects to find, what protocols get activated, to which facility the patient gets routed, and how quickly that patient receives definitive care.

For most of its history, EMS operated without knowing what happened to the patient after emergency department handoff. Medics made decisions, transferred care at the emergency department doors, and moved on to the next call.

That divide is closing.

In today's highest-functioning systems, EMS clinicians can see a patient's ED diagnosis, key lab and radiology findings, and patient outcome after transport. When that kind of outcome data becomes available, it consistently changes best practices, improves performance and yields better patient outcomes.

The same evolution is now beginning in the dispatch center where, for the first time, dispatchers are learning what happened to the patient after the call—and where the clinical implications are already becoming measurable.

Data in Action: Examining Stroke Recognition at Dispatch

The 2026 ESO EMS Index examined 13,700 ED-confirmed stroke encounters with emergency medical dispatch data. When dispatch identified a call as a potential stroke, EMS clinicians recognized it as the primary impression 73% of the time and completed the stroke bundle at nearly the same rate (72%), but when the call was categorized differently — falls, weakness, altered mental status — recognition dropped to 47%.

Stroke doesn't always present as stroke on a 9-1-1 call. The caller may describe a fall or confusion; the opportunity is in refining that initial filter through evidence — and that requires linking dispatch decisions to clinical outcomes at scale.

The Appropriate Response Question

Stroke illustrates what happens when dispatch categorization can be measured against a clinical endpoint. Apply that across the entirety of dispatch output and the question the CARE Act is built on emerges: Which calls could be safely managed through alternative care pathways?

ESO's collaborative research with Johns Hopkins reviewed 1.7 million incidents from eight EMS systems. Time-critical interventions and ED outcomes tracked with increasing dispatch acuity levels, as expected. But the study also identified that at least 8% of calls were eligible for alternative disposition, a finding that intersects directly with the CARE Act's premise.

Separately, a national analysis of 9.5 million EMS encounters published in Health Affairs Scholar found that 3% of patients accounted for 16% of all 9-1-1 responses. The patients with the highest utilization made a repeat request within a median of 10 days, were transported at higher rates than those who called only once a year,+ but were 40% less likely to be admitted. We can continue to build a patient-centric response, as these data indicate such patients may be better served in alternative care pathways rather than repeat trips to the emergency department. 

Findings such as these offer a starting point for a conversation that will look different in every system. What works for a large urban agency won't translate to a mid-size county service or a rural department, and building the evidence base for alternative care pathways demands data from across that spectrum to account for differences in call patterns, community health profiles and what each system can realistically offer.

From Recognition to Infrastructure

Congress recognized dispatchers as protective service workers when the Senate passed the Enhancing First Response Act in September 2025 — correcting a federal classification that had grouped them alongside nonemergency providers. The CARE Act takes a different step, exploring reimbursement structures that reflect what EMS providers already do.

What both pieces of legislation assume, but neither provides, is the evidence architecture needed to determine which calls can be managed through alternative care pathways like community paramedicine, treatment in place, telemedicine or referral to primary care.

Refining dispatch protocols, identifying generalizable patterns and learning which interventions improve outcomes across diverse systems requires standing research networks that can ask and answer questions continuously.

That infrastructure is emerging. Research consortia linking dispatch decisions to patient outcomes across dozens of agencies — urban, suburban, rural — are being built to iterate through questions to establish best practices with high-acuity clinical conditions or less acute conditions that may be better served in alternative care pathways. 

For hospital and health system leaders, dispatch quality affects downstream care quality in ways the field can now measure. The 26-percentage-point gap in stroke recognition is just one example. The broader question — which patients in the emergency care chain could be served differently, earlier and more effectively — will require the same kind of continuous, outcomes-linked evidence.

The policies are already being written. The field is now building the evidence base to ensure that when an emergency medical dispatcher picks up the next 9-1-1 call, the decision that follows is continuously informed by what happened to every patient before.

About the Author

Brent Myers, M.D., MPH, FACEP, FAEMS is the chief medical officer of ESO and an internationally recognized expert in the area of Emergency Medical Services (EMS), particularly as it relates to systems of care, performance improvement and population management.