Table 1 Original version of CCHR and NOC

1(A) Canadian CT head rule

Computed tomography is only required for patients with minor head injury with any 1 of the following findings: patients with minor head injury who present with a Glasgow Coma Scale score of 13–15 after witnessed loss of consciousness, amnesia, or confusion

High risk for neurosurgical intervention

 1. Glasgow Coma Scale score lower than 15 at 2 h after injury

 2. Suspected open or depressed skull fracture

 3. Any sign of basal skull fracture

 4. Two or more episodes of vomiting

 5. 65 years or older

Medium risk for brain injury detection by computed tomographic imaging

 6. Amnesia before impact of 30 or more minutes

 7. Dangerous mechanism

From Stiell et al. (2011)

1(B) New Orleans criteria

Computed tomography is required for patients with minor head injury with any 1 of the following findings. The criteria apply only to patients who also have a Glasgow Coma Scale score of 15

 1. Headache

 2. Vomiting

 3. Older than 60 years

 4. Drug or alcohol intoxication

 5. Persistent anterograde amnesia (deficits in short-term memory)

 6. Visible trauma above the clavicle

 7. Seizure

From Haydel et al. (2001)