Patient selection: isolated head trauma, age < 2 years, not at high risk for traumatic brain injury (all of GCS=15, no palpable skull fracture, normal level of consciousness)
High risk for traumatic brain injury - one or more of the following: GCS < 15, altered level of consciousness, or palpable skull fracture.
Predictors for a skull fracture:
(1) age < 2 months
(2) parietal or occipital hematoma
In the study population of 811, 6% had a skull fracture.
Of 94 patients with a hematoma, 40% had a skull fracture.
Of 56 patients less than 2 months old and without a hematoma, 14% had a skull fracture.
Of the remaining patients only 0.5% had a skull fracture (3 out of 661).
Overall the sensitivity ranged from 0.89-0.94 with a specificity of 0.86.
To detect more cases the age predictor could be changed to <= 3 months. This would give the rule a sensitivity of 98% and specificity of 82%.
