Have you read either of these studies John? In the past whenever you've posted like this you've not actually read the paper.
If you have ... which I doubt ... what do you make of the finding that following the logic of "small sample size correlation suggests cause" you would have to also conclude that helmets _caused_ Australians to suffer more severe injuries to other body parts:
The other body regions demonstrated significant differences in the AIS scores with significantly more serious injuries (AIS≥3) of the chest, abdominal and extremities regions in the Australian group.
Does that not suggest to you that perhaps looking at correlations obtained from small sample sizes is problematic?
Do you remember this point being made to you years ago?
In addition for all the "helmut saaaayyvveed mah life" people... read it again ... a bit more carefully than John... spoiler below
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After adjusting for age, mechanism of injury, GCS and head injury severity in both hospitals, there was no significant difference in mortality
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