Focussed Assessment Sonography for Trauma (FAST) scan is a rapid, non-invasive technique for assessing abdominal trauma. Haemodynamic instability and a positive FAST result are significantly associated. Sensitivities and specificities of FAST scans for blunt and penetrating trauma, reported by Smith and Wood (2013), are 93.1% and 100%, and 90.0% and 100%, respectively.