The effect of helmets on the risk of head and neck injuries among skiers and snowboarders: a meta-analysis.

BACKGROUND The prevention of head injuries in alpine activities has focused on helmets. However, no systematic review has examined the effect of helmets on head and neck injuries among skiers and snowboarders. METHODS We searched electronic databases, conference proceedings and reference lists using a combination of the key words "head injury or head trauma," "helmet" and "skiing or snowboarding." We included studies that used a control group; compared skiers or snowboarders with and without helmets; and measured at least one objectively quantified outcome (e.g., head injury, and neck or cervical injury). RESULTS We included 10 case-control, 1 case-control/case-crossover and 1 cohort study in our analysis. The pooled odds ratio (OR) indicated that skiers and snowboarders with a helmet were significantly less likely than those without a helmet to have a head injury (OR 0.65, 95% confidence interval [CI] 0.55-0.79). The result was similar for studies that used controls without an injury (OR 0.61, 95% CI 0.36-0.92), those that used controls with an injury other than a head or neck injury (OR 0.63, 95% CI 0.52-0.80) and studies that included children under the age of 13 years (OR 0.41, 95% CI 0.27-0.59). Helmets were not associated with an increased risk of neck injury (OR 0.89, 95% CI 0.72-1.09). INTERPRETATION Our findings show that helmets reduce the risk of head injury among skiers and snowboarders with no evidence of an increased risk of neck injury.