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Discussion

CPSC Safety Standard

Today, twelve years after the CPSC rule became effective, there is little evidence that it has significantly reduced injuries associated with bicycles.(95) In fact, the rule is significantly associated with an increase rather than a decrease in the bicycling injury rate.(96) There are a number of possible explanations for this finding. First, the NEISS data may be so inaccurate that this finding is invalid. Evidence, discussed above, suggests the inaccuracy of NEISS particularly with regard to bicycle injuries.(97) Second, it is possible that when consumers learn of the standard, they ride more recklessly.(98) This hypothesis appears unlikely because health insurance coverage that also might encourage reckless riding had no significant effect (at the 95% level) on the injury rate or fatality rate and also had extremely small coefficients. Moreover, unlike automobiles where the driver is surrounded by safety features, the bicycle provides no protection from falls and collisions. Painful "road rash" and more serious injuries should deter any reckless behavior induced by the standard. Third, there may be some other factor correlated with the rule that is the real causal explanation for the increase in the injury rate. Last, the standard may actually do some harm.

This last explanation should not be quickly dismissed. The standard requires that all bicycles be equipped with special reflectors in the front, rear, sides, and pedals. These reflectors were touted as having a 50% increase in performance over conventional reflectors, but while the required rear reflector, for example, does have a broader range of reflectivity, the SAE (conventional) reflector is 7-10 times more bright when illuminated directly.(99)

There is little doubt that the CPSC's reflector standard is inadequate for safe nighttime riding. The CPSC as much as admitted this fact in a press release. The release noted that in 1975, nighttime deaths accounted for 30% of all bicycle fatalities, but in 1982, the figure had risen to 42%. It further urged bicyclists to use front and rear lights, a leg light, and reflective clothing in addition to the mandated reflectors to enhance their nighttime visibility.(100) The NHTSA recently reported that the proportion of bicyclist fatalities occurring between 6:00 P.M. and 6:00 A.M. had risen to 45.6%.(101)

Contrary to the CPSC standard, the National Committee for Uniform Traffic Laws and Ordinances continues to recommend laws requiring a front headlamp and rear reflector or light.(102) Presently, all 50 states and the District of Columbia have adopted this recommendation.(103) Furthermore, at least one court has recognized the inadequacy of CPSC reflectors in a product liability case. It held a retailer negligent for failing to warn a consumer that reflectors are inadequate for nighttime riding and that a light should be installed.(104) The court seems to be saying that if the CPSC reflectors mislead bicyclists into thinking they can safely ride at night, retailers have a duty to correct this misimpression.

However, if the standard were increasing nighttime riding and injuries, it likely would not have a negative correlation (albeit not statistically significant) with fatality rates. Moreover, when specific types of injuries such as groin injuries are examined, the rule had no significant effect on them either.(105) Thus, if it is fair to judge the CPSC by its own database, the evidence appears at best inconclusive and possibly negative.

There are at least three reasons why this result should not be surprising. First, as noted above, the bicycle is inherently unstable so the majority of bicycle-associated injuries are caused by operator error.(106) Even simple misjudgments can cause significant falling injuries.

Second, unlike many products addressed by the CPSC which involve single hazards such as flammability or a sharp cutting edge, the bicycle is a somewhat complex product operated in a complex environment so that the interaction between the product, its maintenance and design; its operator; and the environment, create numerous possible safety issues. The CPSC simply may have been technically incompetent to deal with all of these issues. For example, one of the provisions remanded by the Court of Appeals was the CPSC's heat test for brake blocks of hand brakes. The Court found the distinction between hand and foot brakes to be irrational since only foot brakes are known to fail from excess heat.(107) Forester documents several other examples.(108)

Third and finally, there is little evidence that product defects cause a significant number of bicycle-associated injuries. As Rodgers notes, the CPSC had estimated that 17% of all bicycle-associated injuries are related to product failure and would be addressed by the standard.(109) However, this estimate was derived from a sample of bicycle injuries designed to over-represent product-related injuries. The CPSC consultants who analyzed this biased sample estimated that the proportion of product-related injuries for the population as a whole was 8%.(110)

A lower estimate of the proportion of bicycle-related injuries caused by product failure is given by Jerrold Kaplan's 1974 study of regular adult bicyclists. He found that only 3% of all accidents, even those not severe enough to be reported to NEISS, for these users were caused by product failure.(111) Admittedly, the bicyclists in this sample were likely to maintain their bicycles in better than average condition. Of this small proportion, 3-8% of all injuries, perhaps as many as 90% of the failures occur in bicycles at least three years old.(112) Product standards covering new products cannot prevent eventual product failures from worn components or poorly maintained bicycles. Many bicycle components such as brakes and gearing require periodic maintenance and the replacement of worn parts.(113) Thus, the actual proportion of injuries which the CPSC could have possibly effected through a product standard is probably less than 2% -- far below its 20% goal across all products.

That only a very small proportion of bicycle accidents are caused by product defects is confirmed by casual observation of product liability suits. Paul Hill, author of BICYCLE LAW AND PRACTICE, notes: "[t]here are relatively few reported bicycle product liability cases."(114) He presents 13 reported cases and a couple of others.(115) I have found two additional cases.(116)

By comparison, all terrain vehicles, which are associated with only 240 deaths annually and 86,400 other injuries in 1986 over only 6.7 million users, are the subject of over 300 product liability law suits reportedly currently pending against the industry leader. A coalition of 110 plaintiffs' lawyers has formed the ATV Litigation Group to share information.(117) This coalition and the number of pending suits despite the comparatively small number of injuries indicates the products liability bar's belief that all terrain vehicles may be defectively designed.(118) Apparently the bar has no such belief about the ATVs' older cousin, the two wheeled, non-motorized bicycle.

Helmet Usage

In contrast to the bleak safety results of the CPSC standard, there is some evidence, albeit contradictory, that the market development of safety helmets has had a positive impact on safety.(119) The multiple regression results presented here indicate a significant positive or an insignificant relationship between helmet usage and fatality rates. This suggestion that helmet use may be increasing fatalities appears contradicted by the significant negative relationship between helmet usage and the proportion of injuries that are head injuries. Since there are many times the number of head injuries than fatalities, head injuries are more likely to show an effect from the small amount of helmet use. It would therefore seem that the head injury finding is more credible than the fatality rate evidence. Indeed, medical studies suggest that head injuries are the primary cause of bicycling fatalities.(120) In addition, a significant simple correlation of -0.64 was found between helmet usage and fatality rates, suggesting that with better data a stronger relationship might be found.

Perhaps even more compelling than the statistical evidence presented here, are medical studies that independently establish the beneficial safety effects of helmet usage. A recent controlled study by Thompson et al. compared 235 patients with head injuries received while bicycling to 433 other patients with non-head bicycling injuries and 558 population controls who were demographically matched to the head injury group. Unconditional logistic-regression techniques were used to calculate that riders who used helmets had an 85% reduction in their risk of receiving head injury.(121)

An Australian study also suggests that helmets are effective in reducing head injuries related to bicycle use. Dorsch et al. surveyed club members to find 197 bicyclists who received a blow to the head or helmet in their most recent crash. They found a statistically significant difference in the severity of injury between helmeted riders and unhelmeted riders. They suggest that 90% of deaths due to head injury could be prevented by the use of hardshell helmets.(122)


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