95% CI for rates of imaging or management that might be expected for 100 patients attending the emergency department with a head injury (modelled by Monte-Carlo simulation)
| Skull radiograph | CT scan | Hospital admission | |
|---|---|---|---|
| Actual management | 16.8–33.2% | 0–2.7% | 0.13–7.4% |
| Royal College of Surgeons guidelines | 40.6–60.3% | 0–3.9% | 1.9–12.0% |
| NICE guidelines | 0–1.3% | 3.2–14.2% | 0–3.8% |
| NICE guidelines with 3 or more vomits in the under 12s as the criteria for vomiting | 1.5–11.1% |