Table 1 Canadian CT head rule and New Orleans Criteria

• GCS score, 15 at two hours after injury

• Headache

• Suspected open or depressed skull fracture

• Vomiting

• Any sign of basal skull fracture (hemotympanum, “panda” eyes, cerebrospinal fluid otorrhoea, Battle’s sign).

• Older than 60 years

• Vomiting more than once

• Drug or alcohol intoxication

• Age >65 years

• Persistent anterograde amnesia (deficits in short-term memory)

Medium risk (for brain injury on CT)

• Persistent retrograde amnesia of greater than 30 minutes

• Visible trauma above the clavicle

• Dangerous mechanism of injury (pedestrian struck by vehicle, ejection from vehicle, fall from greater than three feet or five stairs)

• Seizure