A case-control study of the effectiveness of bicycle safety helmets in preventing facial injury. Effectiveness of bicycle helmets in preventing head injury in children: case-control study. The effectiveness of bicyclist helmets: a study of 1710 casualties. Effectiveness of bicycle safety helmets in preventing head injuries. A case-control study. Effectiveness of bicycle safety helmets in preventing serious facial injury. Injury patterns in cyclists attending an accident and emergency department: a comparison of helmet wearers and non-wearers. A case-control study of the effectiveness of bicycle safety helmets.
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 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. During the 1980s, a sustained campaign increased the rates of helmet use of Victorian bicyclists. The efficacy of helmet use was evaluated by comparison of crashes and injuries (AIS-1985) in 366 helmeted (261 Australian Standard approved and 105 non-approved) and 1344 unhelmeted casualties treated from 1987 through 1989 at Melbourne and Geelong hospitals or dying before hospitalization. Head injury (HI) occurred in 21.1% of wearers of approved helmets and in 34.8% of non-wearers (p < 0.001). The AIS scores were decreased for wearers of approved helmets (p < 0.001), face injuries were reduced (p < 0.01), and extremity/pelvic girdle injuries increased (p < 0.001) and the overall risk of HI was reduced by at least 39% and face injury by 28%. When casualties with dislodged helmets were excluded, HI was reduced 45% by approved helmets. Head injury reduction by helmets, although substantial, was less than that found in a similar study in Seattle, Washington. 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. 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 study circumstances of bicycle accidents and nature of injuries sustained and to determine effect of safety helmets on pattern of injuries.
                Prospective study of patients with cycle related injuries.
                Accident and emergency department of teaching hospital.
                1040 patients with complete data presenting to the department in one year with cycle related injuries, of whom 114 had worn cycle helmets when accident occurred.
                Type of accident and nature and distribution of injuries among patients with and without safety helmets.
                There were no significant differences between the two groups with respect to type of accident or nature and distribution of injuries other than those to the head. Head injury was sustained by 4/114 (4%) of helmet wearers compared with 100/928 (11%) of non-wearers (P = 0.023). Significantly more children wore helmets (50/309 (16%)) than did adults (64/731 (9%)) (P < 0.001). The incidence of head injuries sustained in accidents involving motor vehicles (52/288 (18%)) was significantly higher than in those not involving motor vehicles (52/754 (7%)) (chi 2 = 28.9, P < 0.0001). Multiple logistic regression analysis of probability of sustaining a head injury showed that only two variables were significant: helmet use and involvement of a motor vehicle. Mutually adjusted odds ratios showed a risk factor of 2.95 (95% confidence interval 1.95 to 4.47, P < 0.0001) for accidents involving a motor vehicle and a protective factor of 3.25 (1.17 to 9.06, P = 0.024) for wearing a helmet.
                The findings suggest an increased risk of sustaining head injury in a bicycle accident when a motor vehicle is involved and confirm protective effect of helmet wearing for any bicycle accident. 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.
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.