Trauma is a major cause of morbidity and mortality world-wide. In **blinded** between 2019-2020, there were 527,000 hospitalizations and 13,400 deaths due to injury. This makes trauma the leading cause of death for people below the age of 44 years old, accounting for 8.4% of the burden of disease, and costing the health system 8.9 billion dollars [1]. It remains a significant challenge for the health care system and clinicians in trying to achieve the best patient outcomes while balancing the appropriate use of valuable resources.

A key diagnostic tool in the assessment of trauma patients is the use of whole-body computed tomography (CT). It is both sensitive and specific, reproducible at low cost, and accessible to most emergency departments even in a regional or remote setting. Minimizing the time to diagnosis is essential in reducing morbidity and mortality and reducing the length of hospital stay [2]. CT allows for rapid and accurate radiological assessment for underlying injuries especially in a cohort of patients where significant chest or abdominal injuries may be initially occult on initial assessment. In their 2006 study, Salim et al. [3] assessed the injury pattern of 1000 patients after blunt trauma. They showed that up to 19% of patients with normal abdominal examinations were later found to have evidence of injury on their CT scan, and significant injuries were detected which were otherwise clinically occult including blunt aortic injury. Based on their results, the authors suggest a liberal use of whole-body CT (WBCT) in patients with multisystem injury.

The liberal use of CT without judgement should be considered within a range of potential risks. There is a stochastic radiation risk associated with the use of ionizing radiation in a cohort of patients which is typically young [1]. In addition, the use of IV contrast is not entirely benign, in fact the risk of death following IV iodinated contrast administration is approximately 0.9 per 100,000, and there is also a risk of contrast nephropathy in those with pre-existing renal impairment [4]. In a busy tertiary hospital there is also cost and opportunity cost to consider, particularly at peak periods when many patients may concurrently be awaiting CT scan and patients may wait based on a triaging system. Conversely, emergency departments are time-pressured, and a ‘negative’ CT may also facilitate early discharge in well patients. This is a key balance to find between scanning the correct patients and not scanning those who are clinically well with a low-energy mechanism of trauma. Ideally, this decision should be driven by evidence.

However, what remains to be assessed is exactly which patients need a scan and which may not need a scan, a decision important to make soon after the patient arrives and is assessed using available objective information. It is well acknowledged that the energy absorbed into the patient as a result of the mechanism of injury has a strong association with the development of subsequent injuries [3]. As such, documentation of the mechanism is a vital component of risk-assessment and trauma reception.

The Canadian cervical spine rules are an example of an imaging pathway which recommends the use of CT based on mechanism of injury [5]. However, no such pathways exist for imaging of the body region.

This study aimed to identify the relationship between specific mechanisms of injury (MOI) and the finding of traumatic injuries on WBCT imaging at the time of presentation. The goal was to provide data to drive implementation of evidence-based CT scanning based on mechanism of injuries which are likely to identify an injury.