Clinical decision rules for the assessment of mild head injury, used in combination with clinical judgement, can inform the use of head imaging

Context CT is currently the primary modality for investigating possible intracranial injury. The benefit of CT scanning for head injury in certain circumstances was recognised more than 30 years ago,1 but only recently have restrictive protocols based on specialist authorisation given way to a liberal approach with unrestricted access to CT scans in most high income countries. Recently, the long-term effects of radiation have been re-emphasised along with the cost of indiscriminate CT scanning, highlighting the need to determine the optimal use of CT scans for