Old 10-22-08, 11:05 PM
  #13  
closetbiker
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Originally Posted by GIFCo147
And yet, the American College of Emergency Physicians, American Academy of Pediatrics, World Health Organization, and the American College of Surgeons actively promote helmet use as beneficial!
and they say,

"The bicycle helmet is a very effective device that can prevent the occurrence of up to 88% of serious brain injuries"

any use of this 88% stat shows a gross ignorance of the research.

First this figure has been admitted by the authors of the study it came from is incorrect (It also didn't help that the author had been involved in helmet promotion before conducting the study). Analysis by an independent statistician of the full data set showed that the figures for lower-body injuries were similar; in other words, the helmeted riders were "protected" as much from broken legs as from head injuries. The study does not distinguish facial injuries from other head injuries, although helmets would not prevent the former. The figure was later adjusted significantly downward by the authors yet the 88% figure is still quoted, revealing gross ignorance of those quoting it.

The proper use of the (incorrect) figure would be up to 88% as in there were 3 groups of children who simply fell off their bicycles and went to health care facilities and only the group of 0-4 year olds represented this high figure. The groups of 5 - 10 year olds had a 42% reduction and 10 - 14 year olds had a 23% reduction, but even this figure is a misrepresentation of the odds ratio.

The authors calculate an odds ratio and present it as meaning that helmets prevent this proportion of injuries. This is false because odds ratios tend to overstate relative positions. For example, suppose that in a sample of 100 men, 90 have drunk wine in the previous week, while in a sample of 100 women only 20 have drunk wine in the same period. The odds of a man drinking wine are 90 to 10, or 9:1, while the odds of a woman drinking wine are only 20 to 80, or 1:4 = 0.25:1. Now, 9/0.25 = 36, so the odds ratio is 36, showing that men are much more likely to drink wine than women. But actually men are only 4.5 times more likely to have drunk wine than women.

It might also be of significance to note that not a single helmeted cyclist in this study had been struck by a motor vehicle. Not so for the group of cyclists without helmets. The authors were quoted to have said, "We cannot completely rule out the possibility that more cautious cyclists may have chosen to wear helmets and also had less severe accidents".

So the AMERICAN ACADEMY OF PEDIATRICS should do a little more careful research instead of simply parroting previous research that they haven't checked to be valid before publishing.

Last edited by closetbiker; 10-22-08 at 11:17 PM.
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