Objectives: Recent research has shown the measurement of posttraumatic amnesia (PTA) using the Revised−Westmead PTA Scale (R−WPTAS) is a better measure of cognitive change in individuals following mild traumatic brain injury (mTBI) than using the Glasgow Coma Scale (GCS) (Shores et al. 2008). The aim of the study is to demonstrate the Abbreviated-Westmead PTA Scale (A−WPTAS), a combined form of the GCS (orientation questions and GCS eye opening and motor response scores) and the memory items (3 picture cards) from the R−WPTAS, is capable of identifying the resolution of PTA in participants following mTBI. Method: A multicentre randomised group design, based on the revised CONSORT guidelines. Participants, aged 18 to 65 years, who presented consecutively to the Emergency Department (ED) of three hospitals, were eligible if they had sustained a mTBI or a non−brain physical injury. Each hospital had four groups (non−brain injured control R−WPTAS, non−brain injured control A−WPTAS, mTBI R−WPTAS, mTBI A−WPTAS). Estimates from power analysis suggested a sample size of 26 per group (104 patients from each hospital giving a total of 312 patients). Results: Hypotheses to be tested include: 1) Patients who present to an ED with a non-brain physical injury will perform better on the R-WPTAS, A-WPTAS, and the Westmead Selective Reminding Test (WSRT) than patients with a mTBI; 2) performances on the R-WPTAS and A-WPTAS and the WSRT (the reference memory test) in mTBI patients will not be different, and 3) performances on the R-WPTAS, A-WPTAS and the WSRT will not be affected by pain severity, acute posttraumatic stress symptoms, alcohol levels and opioids. The sample to date comprises of 78 mTBI and 110 non-brain injured trauma controls. Conclusions: The results will be discussed.