A case-control study of the effectiveness of bicycle safety helmets in preventing facial injury. Effectiveness of bicycle safety helmets in preventing head injuries. A case-control study. Bicycle safety helmet legislation and bicycle-related non-fatal injuries in California. A case-control study of the effectiveness of bicycle safety helmets. Effectiveness of bicycle safety helmets in preventing serious facial injury. Effectiveness of bicycle helmets in preventing head injury in children: case-control study. Physicians promoting bicycle helmets for children: a randomized trial.
In a case-control study we sought to assess the potential effectiveness of helmets in preventing facial injuries. Our study included 212 bicyclists with facial injuries and 319 controls with injuries to other body areas, who were treated in emergency rooms of five Seattle area hospitals over a one-year period. Using regression analyses to control for age, sex, education and income, accident severity, and cycling experience we found no definite effect of helmets on the risk of serious facial injury (odds ratio 0.81; 95 percent confidence interval = 0.45, 1.5), but protection against serious injuries to the upper face (odds ratio 0.27; 95% CI = 0.1, 0.8). No protection was found against serious injuries to the lower face. The independent effect of helmet use on facial injury was difficult to isolate due to the association of head and facial injuries. Our results suggest that bicycle helmets as presently designed may have some protective effect against serious upper facial injuries. To examine the protective effectiveness of bicycle helmets in 4 different age groups of bicyclists, in crashes involving motor vehicles, and by helmet type and certification standards.
                Prospective case-control study
                Emergency departments (EDs) in 7 Seattle, Wash, area hospitals between March 1, 1992, and August 31, 1994.
                Case subjects were all bicyclists treated in EDs for head injuries, all who were hospitalized, and all who died at the scene. Control subjects were bicyclists treated for nonhead injuries.
                There were 3390 injured bicyclists in the study; 29% of cases and 56% of controls were helmeted. Risk of head injury in helmeted vs unhelmeted cyclists adjusted for age and motor vehicle involvement indicate a protective effect of 69% to 74% for helmets for 3 different categories of head injury: any head injury (odds ratio [OR], 0.31; 95% confidence interval [CI], 0.26-0.37), brain injury (OR, 0.35; 95% CI, 0.25-0.48), or severe brain injury (OR, 0.26; 95% CI, 0.14-0.48). Adjusted ORs for each of 4 age groups (<6 y, 6-12 y, 13-19 y, and > or = 20 years) indicate similar levels of helmet protection by age (OR range, 0.27-0.40). Helmets were equally effective in crashes involving motor vehicles (OR, 0.31; 95% CI, 0.20-0.48) and those not involving motor vehicles (OR, 0.32; 95% CI, 0.20-0.39). There was no effect modification by age or motor vehicle involvement (P=.7 and P=.3). No significant differences were found for the protective effect of hard-shell, thin-shell, or no-shell helmets (P=.5).
                Bicycle helmets, regardless of type, provide substantial protection against head injuries for cyclists of all ages involved in crashes, including crashes involving motor vehicles. The objective of this study was to determine whether the bicycle safety helmet legislation in California, enacted in 1994, was associated with statistically significant reductions in head injuries among bicyclists aged 17 years and under who were subjected to the law. The study used 44,069 patient discharge cases from all public hospitals in California, from 1991 through 2000, and a case-control design to make direct comparisons between those subjected to the law (Youth) and those who were not (Adult) across the pre- and post-legislation periods. An aggregate data analysis approach and a pooled disaggregate data fitting technique using multinomial logit models were applied. The legislation was found to be associated with a reduction of 18.2% (99% confidence interval: 11.5-24.3%) in the proportion of traumatic brain injuries (Head-TBI) among Youth bicyclists. The proportions of other head, face, and neck injuries were not significantly changed across the pre- and post-legislation periods in this age group but there was a corresponding increase of 9% (5-13%) in the proportion of all other injuries. On the other hand, there was no statistically significant change in the proportions of injury outcomes for Adult bicyclists. The youngest riders, aged 0-9 years, had the greatest decrease in the proportion of Head-TBI. The reduction was the same for motor vehicle and non-motor-vehicle-related incidents. The bicycle safety helmet legislation was associated with a decrease in the likelihood of Head-TBI for non-urban residents but not for urbanites, for males but not for females, and for Whites, Asians, and Hispanics, but not Blacks and others. Bicycling accidents cause many serious injuries and, in the United States, about 1300 deaths per year, mainly from head injuries. Safety helmets are widely recommended for cyclists, but convincing evidence of their effectiveness is lacking. Over one year we conducted a case-control study in which the case patients were 235 persons with head injuries received while bicycling, who sought emergency care at one of five hospitals. One control group consisted of 433 persons who received emergency care at the same hospitals for bicycling injuries not involving the head. A second control group consisted of 558 members of a large health maintenance organization who had had bicycling accidents during the previous year. Seven percent of the case patients were wearing helmets at the time of their head injuries, as compared with 24 percent of the emergency room controls and 23 percent of the second control group. Of the 99 cyclists with serious brain injury only 4 percent wore helmets. In regression analyses to control for age, sex, income, education, cycling experience, and the severity of the accident, we found that riders with helmets had an 85 percent reduction in their risk of head injury (odds ratio, 0.15; 95 percent confidence interval, 0.07 to 0.29) and an 88 percent reduction in their risk of brain injury (odds ratio, 0.12; 95 percent confidence interval, 0.04 to 0.40). We conclude that bicycle safety helmets are highly effective in preventing head injury. Helmets are particularly important for children, since they suffer the majority of serious head injuries from bicycling accidents. To assess the effectiveness of helmets in preventing facial injuries.
                Case-control study between March 1, 1992, and August 31, 1994.
                Seven Seattle, Wash, area hospitals including the regional trauma center and a large staff-model health maintenance organization.
                Cases were patients with serious facial injury, ie, fractures or lacerations; controls were patients who had injuries other than facial. Minor facial injuries were excluded to avoid ascertainment bias in those seeking care for serious injuries to other areas.
                Serious facial injuries occurred to 700 (20.7%) patients. Helmets were used by 47% of cases and 57% of controls. After adjusting for age, sex, speed, and surface, we found that helmets reduced the risk of injury to the upper face (odds ratio [OR], 0.36; 95% confidence interval [CI], 0.26-0.49) and middle face (OR, 0.35; 95% CI, 0.24-0.50) but had no significant effect on serious injury to the lower face (OR, 0.88; 95% CI, 0.72-1.07).
                Bicycle helmets offer substantial protection for the upper and mid face in addition to their known protection against head injuries. Helmets do not appear to offer any protection for the lower face. To examine the risk of injury to the head and the effect of wearing helmets in bicycle accidents among children.
                Case-control study by questionnaire completed by the children and their carers.
                Two large children's hospitals in Brisbane, Australia.
                445 children presenting with bicycle related injuries during 15 April 1991 to 30 June 1992. The cases comprised 102 children who had sustained injury to the upper head including the skull, forehead and scalp or loss of consciousness. The controls were 278 cyclists presenting with injuries other than to the head or face. A further 65 children with injuries to the face were considered as an extra comparison group.
                Cause and type of injury, wearing of helmet.
                Most children (230) were injured after losing control and falling from their bicycle. Only 31 had contact with another moving vehicle. Children with head injury were significantly more likely to have made contact with a moving vehicle than control children (19 (19%) v 12 (4%), P < 0.001). Head injuries were more likely to occur on paved surfaces than on grass, gravel, or dirt. Wearing a helmet reduced the risk of head injury by 63% (95% confidence interval 34% to 80%) and of loss of consciousness by 86% (62% to 95%).
                The risk of head injury in bicycle accidents is reduced among children wearing a helmet. Current helmet design maximises protection in the type of accident most commonly occurring in this study. Legislation enforcing helmet use among children should be considered. Head injury is the leading cause of death and serious morbidity in bicycle accidents. There is good evidence to recommend helmets, yet few children wear them. We evaluated helmet promotion in a randomized trial targeting children presenting to primary care settings for routine ambulatory care. The intervention consisted of physician counseling and take-home pamphlets. The study involved 339 families, 167 in the intervention group and 172 in the control group. In a follow-up telephone call, 2 to 3 weeks later, only 7.2% of the intervention group had purchased helmets, compared with 7.0% of the control group (chi 2 = 0.0056, P = .94). During the latter half of the study, bicycle safety received considerable media attention in Ottawa, and the provincial medical society sponsored a $5 discount campaign. Therefore both groups were subject to community "co-intervention." Nonetheless, we were surprised that physician counseling made no additional impact. Our results and the success of certain community programs suggest that physicians interested in helmet promotion would do better to participate in the design and implementation of multidisciplinary campaigns.
Helmets reduce bicycle-related head and facial injuries for bicyclists of all ages involved in all types of crashes, including those involving motor vehicles. Our response to comments from critics are presented in the Feedback section.