Variation in prehospital use and uptake of the national Field Triage Decision Scheme

The Field Triage Decision Scheme is a national guideline that has been implemented widely for prehospital emergency medical services (EMS) and trauma systems. However, little is known about the uptake, modification, or variation in field application of triage criteria between trauma systems.

To describe and compare the use of field triage criteria by EMS personnel in six regions, including the timing of guideline uptake and the use of nonguideline criteria.

This was a retrospective cohort study of injured children and adults transported by 48 EMS agencies to 105 hospitals (trauma centers and non-trauma centers) in six Western U.S. regions from 2006 through 2008. We used probabilistic linkage to match patient-level prehospital information from multiple sources, including EMS records, base-hospital phone communication records, and trauma registry data files. Triage criteria were evaluated individually and grouped by "steps" (physiologic, anatomic, mechanism, and special considerations). We used descriptive statistics to compare the frequency of triage criteria use (overall and between regions) and to evaluate the timing of guideline uptake across multiple versions of the guidelines.

A total of 260,027 injured patients were evaluated and transported by EMS over the three-year study period, of whom 46,414 (18%) met at least one field triage criterion and formed the primary sample for analysis. The three most common criteria cited (of 33 in use) were EMS provider judgment (26%), age <5 or >55 years (10%), and Glasgow Coma Scale (GCS) score <14 (9%). Of the 33 criteria in use, five (15%) were previously retired from the guidelines and seven (21%) were never included in the guidelines. 11,048 (24%) patients had more than one criterion applied (range 1-21). There was large variation in the type and frequency of criteria used between systems, particularly among the nonphysiologic triage steps. Only one of six regions had translated the most recent guidelines into field use within two years after release.

There is large variation between regions in the frequency and type of field triage criteria used. Field uptake of guideline revisions appears to be slow and variable, suggesting opportunities for improvement in dissemination and implementation of updated guidelines.