To determine the optimal imaging strategy for young children with minor head injury considering health-related quality of life and radiation risk. In children with minor head trauma, the risk of missing a clinically important traumatic brain injury (ciTBI) must be weighed against the risk of radiation-induced malignancy from computed tomography (CT) to assess impact on public health.

We included children <2 years old with minor blunt head trauma defined by a Glasgow Coma Scale score of 14-15. We used decision analysis to model a CT-all versus no-CT strategy and assigned values to clinical outcomes based on a validated health-related quality of life scale: (1) baseline health; (2) non-ciTBI; (3) ciTBI without neurosurgery, death, or intubation; and (4) ciTBI with neurosurgery, death, or intubation >24 hours with probabilities from a prospective study of 10000 children. Sensitivity analysis determined the optimal management strategy over a range of ciTBI risk.

The no-CT strategy resulted in less risk with the expected probability of a ciTBI of 0.9%. Sensitivity analysis for the probability of ciTBI identified 4.8% as the threshold above which CT all becomes the preferred strategy and shows that the threshold decreases with less radiation. The CT all strategy represents the preferred approach for children identified as high-risk.

Among children <2 years old with minor head trauma, the no-CT strategy is preferable for those at low risk, reserving CT for children at higher risk.