Project Summary

COVID-19-Related Project Enhancement

COVID-19 affects care in many ways for patients who may be having a stroke. Patients may be delaying calling emergency services about strokes. If patients delay getting care, it may increase the severity of stroke. For those who call, healthcare providers have changed how they care for patients to reduce the risk of infection. Also, it is unknown how infection with COVID-19 affects stroke patients.

With this enhancement, the research team wants to learn how:

  • The delay in patient calls for strokes affects stroke severity and health outcomes
  • Changes to care affect timing of treatment, such as the time from 911 alert to arriving at the ER or receiving treatment
  • Changes to data collection methods under COVID may be reflected in patient health outcomes three months after they leave the hospital

Enhancement Award Amount: $213,743

This research project is in progress. PCORI will post the research findings on this page within 90 days after the results are final.

What is the research about?

A stroke happens when blood flow doesn’t reach the brain. Strokes can cause serious disability or death. But if strokes are treated quickly, patients may have a better recovery.

Getting patients to the hospital to test for a stroke can take time. In this study, the research team is comparing two ways to test for and treat stroke. One way is in the hospital as usual. The other way is to use mobile stroke units, which are ambulances that have special equipment and health care providers who can diagnose and treat stroke on the spot.

Who can this research help?

Directors of hospitals, fire departments, and emergency medical services can use results from this research when considering how to improve care for stroke.

What is the research team doing?

In Houston, Denver, and Memphis, the research team is setting up mobile stroke units. These ambulances carry a CT scanner and lab equipment that can help diagnose strokes. A stroke team with a neurologist, nurse, CT technician, and emergency medical technician ride in the ambulance. When someone calls 911 about a possible stroke, the stroke team goes to the patient.

First, the stroke team assesses whether the patient might be having a stroke. If a stroke seems likely, the stroke team evaluates the patient with the CT scanner and other tests. The neurologist sends the CT images to the hospital for later use. The stroke team provides treatment right away for patients who have had a stroke and takes all patients to the hospital for care.

During the study, the stroke team is responding to about 6,000 possible strokes across the three cities. The team is alternating providing either mobile stroke service or regular emergency care for people with possible stroke week-by-week until the middle of 2019.

Three months after patients in the study get treatment, the research team is following up to see how a stroke affected each patient’s health.

Emergency medical service providers and companies that make equipment to diagnose stroke are working with the research team to design the ambulances and plan the study. The research team is working with patients who have had a stroke to identify what treatment results to measure.

Research methods at a glance

Design Elements Description
Design Observational: cohort study
Population Adults ages 18 years and older with suspected stroke
  • Treatment via mobile stroke unit
  • Treatment in emergency department

Primary: utility-weight modified Rankin Scale, healthcare utilization, quality of life

Secondary: modified Rankin Scale, time from symptom onset to tPA treatment, symptomatic intracranial hemorrhage, mortality, stroke mimics

Timeframe 90-day follow-up for primary outcomes

Project Information

James Grotta, MD
Memorial Hermann Health System, Memorial Hermann-Texas Medical Center
BEnefits of Stroke Treatment Delivered Using a Mobile Stroke Unit Compared to Standard Management by Emergency Medical Services: The BEST-MSU Study

Key Dates

July 2016
December 2022

Study Registration Information


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Last updated: January 12, 2022