liv | (Reply)

From:

I do mean '89 - Thompson RS, Rivara FP, Thompson DC. New England Journal of Medicine, 1989 v320 n21 p1361-7. 1989.

This started the whole thing off, and is where the 85% and 89% figures for effectiveness come from. http://cyclehelmets.org/1068.html (and the entire site is useful) discusses it in more detail, but the potted summary is that it's pretty dubious.

There is then an enormous collection of papers (often with some non-empty subset of TRT involved) which assume TRT '89 got it right and proceed on that basis.

You've found the Cochrane review from 1999 which is discussed at http://cyclehelmets.org/1069.html ... guess which three people did that review, assuming blithely that they got it right in 1989?

(Also, while this does not prove any misconduct, guess who funded TRT's research? The manufacturers of foam hats...)

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1410838/ is a paper by Dorothy Robinson documenting some of the compelling evidence that no jurisdiction that has introduced and enforced helmet compulsion has produced thereby a significant drop in head injury rates. The only conclusion I can draw from that is that they _don't_ work; speculation as to why is interesting (especially when presented with the intuitively appealing idea that they must) but is ultimately not pertinent.