Jdsk wrote: ↑6 Dec 2021, 6:24pm
What costs do you think that a systematic review would incur? It's mostly people's time.
Looking at the databases used in the 2016 review: PubMed is free, but Embase access is $1500/month, Scopus is price on application reported as $24,380/year for 1-25 users, and Compendex is price on application with no obvious public price.
And there seems to be a large amount of time available to argue about the subject which would be much better spent on evidence-based approaches.
Well, this is mission-critical, isn't it? If helmets were to be forced on cyclists, a lot of people would reduce or stop cycling, to the detriment of all cyclists and arguably the nation. So it gets some time. But maybe not as much as you think, given how fast some people type.
The evidence is not being collected any more. Few seem to care about the evidence now anyway. People have taken their positions for various reasons and entrenched, so it may no longer even be possible to collect good data without a lot of measures to reduce the risk of advocates telling data collectors what they they they want to hear, similar to what you have to do when surveying about sexual activities... and then both extremes will probably attack that methodology!
Goldacre and Spiegelhalter seem increasingly correct: "the current uncertainty [...] is unlikely to be substantially reduced by further research. [...] The enduring popularity of helmets [...may lie...] more with the cultural, psychological, and political aspects of popular debate around risk."
The cost of access to the literature is very low, and probably aero in a realistic study involving an academic partner.
Based on the numbers above, we seem to have different ideas of very low cost and I don't understand aero in that context.