Table 5

 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 radiographCT scanHospital admission
Actual management16.8–33.2%0–2.7%0.13–7.4%
Royal College of Surgeons guidelines40.6–60.3%0–3.9%1.9–12.0%
NICE guidelines0–1.3%3.2–14.2%0–3.8%
NICE guidelines with 3 or more vomits in the under 12s as the criteria for vomiting1.5–11.1%