beardy wrote:Yes I know you'll say motorcycles are different,
They are! and motorcycle helmets are certainly different from cycle helmets as they are actually effective helmets rather than just pieces of expanded polystyrene that just crack in half on hitting something.
Actually... They aren't. Like with bicycle helmets, motorcycle helmets studies have produced mixed results. Almost all of the early studies were taken from data for competitive motorcyclists, because they were the largest group of helmet wearers. Similarly, most places that have implemented motorcycle helmet laws have seen fatalities decrease. Florida repealed their motorcycle helmet law, and saw an increase in motorcyclist fatalities and head injuries. And whilst all the pro-helmet campaigners are jumping up and down saying 'I told you so', a few people looked more closely at the available data...
Is just one example of a study that found that motorcycle helmets may not have the benefit everyone thinks they do. Furthermore, I think it likely that motorcycle helmet studies that do show benefit may have the same sort of bias problems that bicycle helmet studies do.
It is also likely that helmetted motorcyclists engage in risk compensation.
I haven't looked at all of the evidence for motorcycle helmets the way I have for bicycle helmets, but I have a friend in the USA who campaigns against motorcycle helmet laws. He has looked at the evidence, and read lots of studies, and he is just as convinced about the lack of evidence supporting the use of motorcycle helmets as many on the forum are about the lack of evidence supporting the use of bicycle helmets.