Calculating trauma triage precision: effects of different definitions of major trauma

Abstract

BackgroundTriage is the process of classifying patients according to injury severity and determining the priority for further treatment. Although the term “major trauma” represents the reference against which over- and undertriage rates are calculated, its definition is inconsistent in the current literature. This study aimed to investigate the effects of different definitions of major trauma on the calculation of perceived over- and undertriage rates in a Norwegian trauma cohort.MethodsWe performed a retrospective analysis of patients included in the trauma registry of a primary, referral trauma centre. Two “traditional” definitions were developed based on anatomical injury severity scores (ISS >15 and NISS >15), one “extended” definition was based on outcome (30-day mortality) and mechanism of injury (proximal penetrating injury), one ”extensive” definition was based on the “extended” definition and on ICU resource consumption (admitted to the ICU for >2 days and/or transferred intubated out of the hospital in ≤2 days), and an additional four definitions were based on combinations of the first four.ResultsThere were no significant differences in the perceived under- and overtriage rates between the two “traditional” definitions (NISS >15 and ISS >15). Adding “extended” and “extensive” to the “traditional” definitions also did not significantly alter perceived under- and overtriage. Defining major trauma only in terms of the mechanism of injury and mortality, with or without ICU resource consumption (the “extended” and “extensive” groups), drastically increased the perceived overtriage rates.ConclusionAlthough the proportion of patients who were defined as having sustained major trauma increased when NISS-based definitions were substituted for ISS-based definitions, the outcomes of the triage precision calculations did not differ significantly between the two scales. Additionally, expanding the purely anatomic definition of major trauma by including proximal penetrating injury, 30-day mortality, ICU LOS greater than 2 days and transferred intubated out of the hospital at ≤2 days did not significantly influence the perceived triage precision. We recommend that triage precision calculations should include anatomical injury scaling according to NISS. To further enhance comparability of trauma triage calculations, researchers should establish a consensus on a uniform definition of major trauma.

Patient experiences of initial trauma care

“…79 Efforts have been made to evaluate compliance of criteria with over and under triage, and also to see if criteria are accurate to identify patients in need of full trauma team activation. 64 We agree with Lossius et al 13 that consensus on uniform definitions in trauma research should be established to facilitate comparability in trauma research. In Sweden, consensus-based new national criteria for trauma team activation (TTA) was developed in 2016, by an expert panel with the support of a Swedish public insurance company (LÖF).…”

“…Monitoring 'over triage' and 'under triage' is often used as an indication of the trauma care quality. Various methods and algorithms on how to calculate over-and under triage are used in research, 7,[12][13][14][15][16] and therefore, it can be difficult to compare results from different trauma centres.…”

Pre‐hospital critical care by anaesthesiologist‐staffed pre‐hospital services in Scandinavia: a prospective population‐based study

“…According to our findings, a population of 10,000 inhabitants will need at least 25–30 emergency physician primary missions per year. Some over‐triage will be necessary to ensure acceptable sensitivity …”

The civilian validation of the Modified Physiological Triage Tool (MPTT): an evidence-based approach to primary major incident triage

“…Secondary outcomes were to evaluate the performance of the MPTT using a subgroup analysis split by gender, age and mode of injury. For all triage tools sensitivity, specificity, undertriage (1-sensitivity) and overtriage (1-positive predictive value) with 95% CIs were calculated 15. Using a McNemar test, tools with similar performance characteristics were evaluated for any statistically significant difference in performance 16…”