The one not mentioned, who checks the bike over and makes sure his kid is wearing a helmet.
There are several meta-analyses and reviews which synthesize and evaluate the results of multiple case-control studies. A Cochrane review of case-control studies of bicycle helmets by Thompson et al. found that "helmets provide a 63 to 88% reduction in the risk of head, brain and severe brain injury for all ages of bicyclists. Helmets provide equal levels of protection for crashes involving motor vehicles (69%) and crashes from all other causes (68%). Injuries to the upper and mid facial areas are reduced 65%.".
A 2001 meta-analysis of sixteen studies by Attewell et al. found that, compared to helmeted cyclists, unhelmeted cyclists were 2.4 times more likely to sustain a brain injury; 2.5 times more likely to sustain a head injury; and 3.7 times more likely to sustain a fatal injury.
A 2012 re-analysis of the 16 studies in the Attewell meta-analysis, by Elvik, found that, compared to helmeted cyclists, unhelmeted cyclists were 2.5 times more likely to sustain a brain injury; 2.3 times more likely to sustain a head injury; and 4.3 times more likely to sustain a fatal injury.[a] When 5 new head-injury studies were added to the model, Elvik found that unhelmeted cyclists were 1.9 times more likely than helmeted cyclists to sustain a head injury. When head, face and neck injuries were combined, Elvik found that unhelmeted cyclists were 1.4 times more likely than helmeted cyclists to sustain an injury to the head, face or neck. The odds ratio for brain injuries reported by Elvik (95% CI 0.33-0.50) is consistent with the odds ratios using hospital controls reported in the Cochrane review (0.05-0.57 for brain injury and 0.14-0.48 for severe brain injury). In noting that the results of the meta-analysis were inconsistent with the results of the Cochrane review, Elvik may have been referring just to the head injury results (95% CI 0.26-0.37 in the Cochrane review; in Elvik's meta-analysis, 0.38-0.48 using the studies in the Attewell analysis, 0.49-0.59 when 8 new studies were included)."
Same old article!http://en.wikipedia.org/wiki/Bicycle_he ... ead_injury
The doctor diagnosed me with hereditary diarrhoea. I can't understand, I wear a kilt.