Soyons un peu positif

Personnellement, je suis contre une mesure obligatoire sur le port du casque, je le recommande et le porte en tout temps.  Je trouve que le débat est trop émotif et que les ayatollahs du casque en mettent un peu.  Je préfère la sensibilisation, l'éducation et le débat.

Voici une étude hollandaise récente (septembre 2011) sur le sujet.  Assez positif.

Summary
One third of the cyclists who are admitted to hospital with serious injury after a road crash are diagnosed with head or brain injury. Approximately three-quarters of the head and brain injuries among cyclists are caused by crashes that do not involve motorized traffic; as many as nine out of ten young children who sustain head/brain injury, do so in crashes not involving motor vehicles. These are mostly cyclist-only crashes. This type of crash is difficult to prevent, but it is possible to limit the severity of the head and brain injury by wearing a bicycle helmet. According to the most recent and sound estimate, the risk of sustaining head injury is reduced by as much as 42% when a good bicycle helmet is worn correctly; the risk of sustaining brain injury is then reduced by 53%. Research in other countries has shown that the use of bicycles sometimes declines, particularly during the first few years after the introduction of mandatory helmet use. The longer-term effects or the significance of these results with regard to the situation in the Netherlands are not known.

http://www.swov.nl/rapport/Factsheets/UK/FS_Bicycle_helmets.pdf
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