ATCEMS Performance Dashboard > Trauma Scene Interval per Quarter > Performance Measure Definition: Trauma Alert Call-to-Door Interval
Performance Measure Definition: Trauma Alert Call-to-Door Interval

Description: Call-to-Door Interval measures the amount of time between the initial 911 call for a patient, and arrival of that patient at a receiving facility.  It describes the ability of ATCEMS to quickly deliver patients with time-sensitive conditions to definitive care.
Desired Outcome:  Components of the ATCEMS response system – Communications and field personnel – work together to identify and rapidly deliver Trauma Alert patients to appropriate receiving facilities.
Relevance:  This patient population benefits from minimal delays in the prehospital environment.  They need rapid transport to specialized medical facilities that can quickly perform diagnostic and interventional procedures that are not available in the field.
Measure Domain: Clinical care
Type of Measure:  Process

Operational Specifications
Formula Description:  The average call-to-door interval is calculated by adding up the intervals for the appropriate patient population, and dividing by the count of included patients.
The resulting value is reported in decimal minutes format (e.g., 38.7 minutes).
Unit of Analysis:  Patient contacts
  • Numerator: Patients identified as meeting Trauma Alert criteria AND are transported to a receiving facility.  The receiving facility is NOT required to be a Trauma Center for inclusion in this measure.
  • Denominator:  Patients identified as meeting Trauma Alert criteria AND are transported to a receiving facility.
Measure Frequency:  Quarterly
Minimum Population/Sample:  None
Performance Standard:  Average Call-to-Door interval will be 45 minutes or less every quarter.
Acceptable Quality Level:  Not defined
Interval Description:  Call-to-Door Interval begins when the first 911 call for the incident is received, and ends when the patient is recorded in CAD as arriving at the receiving facility.
Reporting Value:  Average interval in decimal minutes.
  • Temporal aggregations (month, hour of day, etc.) are based on the date/time of earliest recorded call pickup. 
  • Other aggregations may be based on alert type, demographic factors, geography, or receiving facility.
Stratification: None
Limitations:  None
Related Measures: None
Notes: “Trauma Alert” is not a term currently used in ATCEMS System Clinical Operating Guidelines or other official sources.  It is used in this setting as a short-hand term for patients meeting Physiological or Anatomical criteria for triage to a Trauma Center.
System performance may vary over time due to patient location.  Specialty care centers are generally located in central Travis County.  As a result, patients in outlying areas of the county will likely face extended call-to-door times due to travel time requirements.  The incidence of patients in such areas may cause significant variation in system performance over time.

ATCEMS Open Performance Dashboard
City of Austin Open Data Portal
ATCEMS System Performance Dashboard
  • Orientation: External
  • Format: Line chart of monthly values, beginning in the first quarter of FY2013-14.
  • Data Source: Open Data table [EMS - Quarterly Clinical Measures – Trauma Alert]

Office of the Medical Director, Austin/Travis County EMS System (2016).  “Clinical Reference CR-30: Regional Trauma System Adult and Pediatric Criteria.” Austin-Travis County Emergency Medical Service System Clinical Operating Guidelines version 021716.

Development Status: Actively reporting 
Definition Version: Version C 
Revision Date: 2017-02-02 
Revised By: David Andersen