Beyond being a group of people who agree with your position, is there anything that makes it clear that this particular group is correct?

One would think that helmet manufacturers are full of "professional helmet engineers" too.

From that viewpoint alone, I'm thankful that the helmet did its job. Even if the helmet was only 50 to 75-percent effective in saving a life, I'd still choose wearing one to the alternative.

Funny thing about all the statistics I've read - not just here, but elsewhere, too - but many only speculate on what may or may not happen if a head injury were to occur. Many of the stats recorded are those that have been reported to authorities, such as those found in deaths as well as those that have required hospitalization. But, just how many crashes go unreported? We really have little or no data on this because many of whom that have had blows to the head while wearing a helmet have gotten up and walked away from the crash, myself included....with a "little headache" and all. With that said, it's really no wonder that we have very little solid evidence that absolutely proves one theory or another. I would honestly think that most of us here would have to agree that we're reaching for and making some rather insubstantial arguments into some rather gray areas here, don't ya think?

It's obvious that there are some collisions that are beyond what helmets could deal with.

Do you normally argue your position by stating tautologies?

It appears that there is only one person on that list that has these attributes!

https://www.cyclecraft.co.uk/digest/effectiveness.pdf

In 1996 Scuffham published a further paper25 looking at the trends in cycle injury in New Zealand
under voluntary helmet use, pre-law. In the period 1989 to 1992, helmet wearing rates increased from
46% to 84% for primary schoolchildren, 23% to 62% for secondary schoolchildren, and 21% to 39%
for adults. During the same period serious injuries to cyclists (all causes) decreased substantially for
children, but not for adults. However, serious head injuries as a percentage of all serious injuries
remained constant for all groups, with no apparent difference between bicycle-only and motor vehicle
related crashes. The percentages of mild concussions and lacerations to the scalp did decrease more
than other cyclist head injuries. Failure to achieve the predicted decline in serious head injury was
thought to be attributable to a number of factors, including the incorrect fitting and wearing of
helmets.

Scuffham noted that benefits from helmet wearing did not appear to have been achieved
post-legislation either, and there was an increase in neck injuries. A separate paper was said to be in
preparation.

Whole population samples have also been created in certain parts of the USA where cycle helmets
have been made compulsory, in most cases just for children. Krygowski26 collected statistics for
cyclist fatalities from the National Highway Transportation and Safety Administration for all states
that had mandatory helmet laws, covering the period 1990 to 1995, as appropriate for when individual
laws were introduced. The data was disaggregated by age group. Krygowski found a slight
downward trend in fatalities, but no startling improvement as helmet use rose upon the introduction of
a law. In most cases gains made in the first years of a law were eroded a year or two later. In
Califomia, with its bigger population, better weather and much more cycling (thus yielding more
robust data), there was no detectable effect at all. A general result of the laws was to reduce
participation in cycling and it is possible that it is this that led to the reduction in fatalities.
Kunich27 analysed cyclist and pedestrian fatalities for the whole of the USA from 1986 to 1996.
During this period helmet use by cyclists rose from close to zero to 30% or more. Although cyclist
fatalities fell during the period, the decline was proportionately less than for pedestrians, and the
continuation of a long-term trend most probably associated with decreased exposure. Kunich
concluded that there is no evidence that cycle helmets are effective in reducing deaths, and quoted
research into football helmets28 that suggested that helmets can even cause new injuries by increasing
the effective size of the head.

Burdett29 carried out a similar analysis for Canada from 1975 to 1997. Fatality trends were similar for
cyclists and pedestrians throughout the period, and both fell. Although cycle helmet use grew from
virtually zero in 1988 to over 30% in 1995 and up to 50% in 1997, there is no detectable impact on
the fatalities recorded.

In Britain a paper from the London Research Centre30 shows cyclist casualties in Greater London
from 1981 to 1996. Despite an increase in cycle helmet wearing from nearly zero to almost 40% over
the decade 1986 to 1996, this has had no noticeable effect on trends for any severity of cyclist
casualty. Furthermore the 'severity ratio' (the proportion of casualties that are serious or fatal) was
higher in the most recent years than in the earliest years of the comparison. Detailed data on cycle use
is needed to refine the analysis, but the variation in cycle use is likely to be small compared with the
increase in helmet use.

Accident statistics31 from Great Britain as a whole and from Cambridge (with its large cycling
population) also show no evidence of a 'helmet effect' – the severity of cyclist injuries continuing to
follow well established trends despite large increases in helmet use.

However, as well as being quoted extensively in favour of helmet wearing, this report has also
received much criticism, although this appears to have reached a much smaller audience. Principal
criticisms are:

The study is non-randomised.

Cyclists wearing helmets were mostly white and riding in parks or on cycle paths
accompanied by adults. Cyclists without helmets were more often black or other races,
riding alone on city streets.

Most of the injuries were minor, and there were no instances of helmeted cyclists in
collision with motor vehicles, but the results were extrapolated to apply to all types of
injury.

The same methodology can be used on other data in the study to show that helmet use also
reduces the risk of injury to other parts of the body by 72%.

The same methodology can be used on other data in the study to show that helmet use also
reduces the risk of injury to other parts of the body by 72%.