[nikisweeting]

THEY DO CONTROL FOR PERCENTAGE!

read the paper he quoted (emphasis mine):

"The severe TBI of 1238 patients were described. The annual incidence and mortality of severe TBI were, respectively, 13.7 per 100,000 and 5.3 per 100,000. The fatality rate increased from 20% in childhood to 71% over 75-year-old. Compared to restrained car occupants, the odds ratio for having a severe TBI was 18.1 (95% confidence interval, CI = 12.8–25.5) for un-helmeted motorcyclists, 9.2 (95% CI = 7.5–11.3) for pedestrians, 6.4 (95% CI = 4.7–8.8) for un-helmeted cyclists, 3.9 (95% CI = 3.1–4.8) for unrestrained car occupants and 2.8 (95% CI = 2.2–3.5) for helmeted motorcyclists."

http://www.sciencedirect.com/science/article/pii/S0001457505...

[Jemaclus]

Per 100,000 what? People who cycle? People in general? Patients with head injuries?