Defining the representativeness heuristic in trauma triage: A retrospective observational cohort study.

Background: Under-triage of severely injured patients presenting to non-trauma centers (failure to transfer to a trauma center) remains problematic despite quality improvement efforts. Insights from the behavioral science literature suggest that physician heuristics (intuitive judgments), and in particular the representativeness heuristic (pattern recognition), may contribute to under-triage. However, little is known about how the representativeness heuristic is instantiated in practice.

Methods: A multi-disciplinary group of experts identified candidate characteristics of "representative" severe trauma cases (e.g., hypotension). We then reviewed the charts of patients with moderate-to-severe injuries who presented to nine non-trauma centers in western Pennsylvania from 2010-2014 to assess the association between the presence of those characteristics and triage decisions. We tested bivariate associations using χ2 and Fisher's Exact method and multivariate associations using random effects logistic regression.

Results: We identified 235,605 injured patients with 3,199 patients (1%) having moderate-to-severe injuries. Patients had a median age of 78 years (SD 20.1) and mean Injury Severity Score of 10.9 (SD 3.3). Only 759 of these patients (24%) were transferred to a trauma center as recommended by the American College of Surgeons clinical practice guidelines. Representative characteristics occurred in 704 patients (22%). The adjusted odds of transfer were higher in the presence of representative characteristics compared to when they were absent (aOR 1.7, 95% CI: 1.4-2.0, p < 0.001).

Conclusions: Most moderate-to-severely injured patients present without the characteristics representative of severe trauma. Presence of these characteristics is associated with appropriate transfer, suggesting that modifying physicians' heuristics in trauma may improve triage patterns.