Under-Triage and Over-Triage Using the Field Triage Guidelines for Injured Patients: A Systematic Review

Objectives: The Field Triage Guidelines (FTG) are used across North America to identify seriously injured patients for transport to appropriate level trauma centers, with a goal of under-triaging no more than 5% and over-triaging between 25% and 35%. Our objective was to systematically review the literature on under-triage and over-triage rates of the FTG. Methods: We conducted a systematic review of the FTG performance. Ovid Medline, EMBASE, and the Cochrane databases were searched for studies published between January 2011 and February 2021. Two investigators dual-reviewed eligibility of abstracts and full-text. We included studies evaluating under- or over-triage of patients using the FTG in the prehospital setting. We excluded studies not reporting an outcome of under- or over-triage, studies evaluating other triage tools, or studies of triage not in the prehospital setting. Two investigators independently assessed the risk of bias for each included article. The primary accuracy measures to assess the FTG were under-triage, defined as seriously injured patients transported to non-trauma hospitals (1-sensitivity), and over-triage, defined as non-injured patients transported to trauma hospitals (1-specificity). Due to heterogeneity, results were synthesized qualitatively. Results: We screened 2,418 abstracts, reviewed 315 full-text publications, and identified 17 studies that evaluated the accuracy of the FTG. Among eight studies evaluating the entire FTG (steps 1–4), under-triage rates ranged from 1.6% to 72.0% and were higher for older (≥55 or ≥65 years) adults (20.1–72.0%) and pediatric (<15 years) patients (15.9–34.8%) compared to all ages (1.6–33.8%). Over-triage rates ranged from 9.9% to 87.4% and were higher for all ages (12.2–87.4%) compared to older (≥55 or ≥65 years) adults (9.9–48.2%) and pediatric (<15 years) patients (28.0–33.6%). Under-triage was lower in studies strictly applying the FTG retrospectively (1.6–34.8%) compared to as-practiced (10.5–72.0%), while over-triage was higher retrospectively (64.2–87.4%) compared to as-practiced (9.9–48.2%). Conclusions: Evidence suggests that under-triage, while improved if the FTG is strictly applied, remains above targets, with higher rates of under-triage in both children and older adults.