PEDIATRICS Vol. 117 No. 6 June 2006, pp. 2190-2195 (doi:10.1542/peds.2005-2603)
Pediatric All-Terrain Vehicle–Related Injuries in Ohio From 1995 to 2001: Using the Injury Severity Score to Determine Whether Helmets Are a Solution
a Division of Emergency Medicine, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio
b Department of Surgery
c Center for Injury Research and Policy, Columbus Children’s Research Institute, Columbus Children’s Hospital, Columbus, Ohio
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ABSTRACT |
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 TOP ABSTRACT METHODSRESULTSDISCUSSIONREFERENCES |
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OBJECTIVE. The goal was to identify regions in Ohio with severe pediatric all-terrain vehicle–related injuries and to determine whether helmet usage was associated with lower injury severity scores.
METHODS. We performed a retrospective review of data for all patients entered into the registries of Ohio’s major pediatric trauma centers for the period of January 1, 1995, to December 31, 2001.
RESULTS. Seven hospitals participated. A total of 285 children were admitted; 2 patients died, and 13 required rehabilitation. The mean age was 11.1 years, with 76.1% of patients being male and 88.1% white. Most patients came from the central and southwestern regions of Ohio. An average of 30 admissions per year occurred from 1995 to 1998, but the number increased to 55 admissions per year from 1999 to 2001. Among the 285 injured children, 869 injuries were sustained; 57% of patients sustained multiple injuries. The most commonly injured body parts were the head (22.3%) and lower extremities (12.6%). The most common injuries sustained were fractures (31.4%) and contusions/abrasions (22.2%). Of patients for whom documentation was available, 72.2% (171 of 237 patients) were not helmeted. There was no significant difference in mean injury severity scores between helmeted and nonhelmeted riders (9.58 vs 9.12). Helmet usage was not associated with a reduction in head/facial injuries.
CONCLUSIONS. All-terrain vehicle–related injuries to children nearly doubled between 1995 to 1998 and 1999 to 2001. Fewer than 30% of injured children were wearing helmets at the time of injury. With the injury severity score as an indicator, helmets provided no significant protection for all-terrain vehicle riders in this pediatric population.
Key Words: injury • all-terrain vehicle • injury severity score
Abbreviations: ATV—all-terrain vehicle • ISS—injury severity score
Three- and 4-wheeled, motorized, recreational vehicles, typically called all-terrain vehicles (ATVs), are designed for off-road use; they have large tires, poor suspension, and high centers of gravity. They may weigh up to 600 pounds, they have 50- to 700-mL engines, and they can reach speeds of up to 75 mph.1 Although age recommendations and warnings about use by children are included with every new ATV sold, resale of older models without labels, lack of education regarding ATV dangers, and inappropriately large models being used by youths are factors in children sustaining injuries.
Recently, ATVs have become faster and more powerful. Furthermore, the number of ATV drivers has increased by 36%, and the number of ATVs in use has increased by 40%.2 As a result, more ATV-related injuries are occurring among US youths. According to the US Consumer Product Safety Commission, there were 6494 ATV-related fatalities from 1982 to 2004, with 186 occurring in the state of Ohio.3 Children <16 years of age accounted for 31% of the deaths between 1982 and 2004.3 ATV-related emergency department visits have more than doubled since 1997, from an estimated 52800 annually to 
136100 in 2004.3 The majority of severe injuries are orthopedic, followed by head injuries.4 Retrospective studies showed that most ATV riders were not wearing helmets when they sustained their injuries.4,5
Laws and regulations regarding ATV usage vary by state. Although every state in the United States requires a child to be at least 15 years of age and to pass a driver’s test to obtain a valid automobile driver’s license, 43 states allow children <12 years of age to operate an ATV, with no requirements for wearing protective gear.6 In the state of Ohio, the minimal age for ATV usage is 12 years, and a license is required only if the ATV is to be operated while crossing public highways or on public lands; no license is required to operate an ATV on private lands, even if the operator is <12 years of age.7 In addition, riders are required to wear a helmet only when riding an ATV on public lands.7
It is well known that helmet usage with other recreational vehicles can reduce the risk of head injuries greatly.8–10 For example, bicycle helmets can reduce head injuries by up to 85% and have been shown to reduce serious facial injuries effectively.8–11 Since the implementation of legislation and regulations, bicycle helmets are worn more often, reducing the morbidity and mortality rates of bicycle-related crashes.12,13 Similarly, wearing a motorcycle helmet may reduce the likelihood of death in a collision by 61%.10 Legislation to enforce the use of motorcycle helmets has been shown to result in significant reduction in mortality rates for motorcycle crashes.14 Also, repealing an established motorcycle helmet law increases the number of fatalities.15 Compared with motorcycle crashes, ATV collisions have similar mortality rates and much higher rates of head injuries.16 For ATVs, a study of riders of all ages showed that helmets could reduce the risk of death by 42%.17 States with helmet legislation are more likely to have youths wear helmets when riding ATVs.18 However, even those states have significant morbidity and mortality rates for youths, which has led many to conclude that children <16 years of age should never ride ATVs.6,18–20
The purpose of this study was to determine whether helmeted children with ATV-related injuries serious enough to warrant admission to the hospital had lower injury severity scores (ISSs) than did children who were not helmeted. A secondary purpose was to identify areas within the state where hospitalized ATV riders resided, so that future interventions can be implemented in higher-risk areas.
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METHODS |
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This was a retrospective, multicenter, epidemiologic study of children <16 years of age who sustained ATV-related injuries in Ohio. Eight hospitals, which admit >85% of pediatric trauma patients in Ohio, were approached to participate in the study. Seven hospitals supplied data, namely, Cincinnati Children’s Hospital Medical Center (Cincinnati), Columbus Children’s Hospital (Columbus), Children’s Medical Center (Dayton), Tod Children’s Hospital (Youngstown), Medical College of Ohio (Toledo), Rainbow Infants’ and Children’s Hospital (Cleveland), and Metro Children’s Hospital (Cleveland). Institutional review board approval was obtained at each participating hospital before initiation of the study.
Cases were identified by using International Classification of Diseases, Ninth Revision, discharge codes, external-cause-of-injury codes when available, and narrative information from hospital trauma registries. Coroner data were not reviewed because there is no centralized source for this information in Ohio. Case subjects were defined as all children <16 years of age who were admitted to a participating hospital between January 1, 1995, and December 31, 2001, as a result of an injury sustained while riding an ATV. Data abstracted included patient demographic features and injury information, including loss of consciousness, date and time of injury, zip code of residence of the injured child, protective gear worn, and description of the injuries sustained (body part and type of injury). To compare rural versus urban communities and ISSs, US Census data were examined. Zip codes delineated as 
50% urban were considered urban for analysis. The outcomes for all patients (whether they lived or died), International Classification of Diseases, Ninth Revision, discharge codes, discharge dispositions, and lengths of hospital stays were also recorded. The ISS for each patient was calculated to assess the severity of injuries and to compare injured children wearing a protective helmet with those without a helmet. The Abbreviated Injury Scale was reviewed for injuries sustained to the head and/or facial region, to compare known helmeted versus nonhelmeted ATV riders. All data supplied by the participating sites and all sustained injuries were included in the analysis.
Data were compiled and analyzed with SPSS software (release 11.5.0; SPSS, Chicago, IL). ArcView mapping software, GIS version 3.2 (Redlands, CA), was used to map zip codes of residence for the injured patients, to determine whether clusters of children with ATV-related injuries could be identified within the state.
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RESULTS |
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TOPABSTRACTMETHODSRESULTSDISCUSSIONREFERENCES |
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During the study period, 285 children <16 years of age were admitted to a participating hospital with an ATV-related injury. Demographic features of injured children are shown in Table 1. Seventy-six percent of the injured patients were male, 88.1% were white, and 57.9% were commercially insured. The mean age of hospitalized children was 11.1 years (range: 1–15 years; SD: 3.4 years). The numbers of children treated at each of the participating hospitals were 68 (23.9%) at Cincinnati Children’s Hospital Medical Center, 6 (2.1%) at Medical College of Ohio, 27 (9.5%) at Metro Children’s Hospital, 9 (3.2%) at Rainbow Infants’ and Children’s Hospital, 137 (48.1%) at Columbus Children’s Hospital, 12 (4.2%) at Tod Children’s Hospital, and 26 (9.1%) at Children’s Medical Center (Dayton, OH). Figure 1 shows a map of the zip codes of residence for all children hospitalized with ATV-related injuries. The majority of injured children resided around the main children’s hospitals and major cities with greater populations of youths in the state.
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Of the 221 children for whom locale of injury was documented, 44% were injured at their home or on a street; 48.5% of the injured patients lived in rural counties. Of the 235 children for whom time of injury was documented, most were injured during the afternoon and evening hours, that is, 21.4% between 12 noon and 4 PM and 40.0% between 4 PM and 8 PM. Seventy-five percent of the injuries occurred between the months of April and September. The average annual number of hospitalizations attributable to ATV-related injuries nearly doubled during the last 3 years of the study (ie, 1999–2001), compared with the preceding 4 years (1995–1998) (55.3 vs 29.8 hospitalizations) (Fig 2).
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Of the 259 patients for whom dispositions were recorded, 244 (85.6%) were discharged from the hospital after hospitalization, 2 died, and 13 went to rehabilitation. Among the 285 injured children, 869 injuries were sustained; 57.1% of the children had multiple injuries. The body parts injured most commonly included the face/neck/head (32.6%), lower extremity (12.6%), and abdomen/pelvis (10.3%). The most common injuries were fractures (31.4%), abrasions/contusions (22.2%), and lacerations (12.3%); 6.0% of injuries were intracranial injuries.
Of the 237 children for whom information about protective gear (eg, helmets, goggles, gloves, or boots) was available, 170 (71.7%) were not wearing any form of protective gear at the time of injury; only 66 (27.8%) were helmeted. The ISS was calculated for 271 patients who were injured; 14 patients had incomplete data, which precluded calculation of the ISS. The mean ISS was 9.2 for the patients for whom data were complete (range: 1–41; SD: 6.0). There was no difference in the mean ISSs between all helmeted and nonhelmeted riders (helmeted: mean: 9.6; SD: 7.0; nonhelmeted: mean: 9.1; SD: 6.8; P = .64). With respect to age, race, and location of residence, helmeted riders had no significant reduction in ISSs, compared with nonhelmeted riders (Table 2). However, it was found that helmeted riders <8 years of age had significantly greater ISSs than did nonhelmeted riders. The mean length of hospital stay was 4.1 days (range: 1–58 days; SD: 6.1 days). There was no significant difference in the lengths of hospital stays between helmeted riders (mean: 4.1 days; SD: 4.6 days) and nonhelmeted riders (mean: 4.2 days; SD: 6.5 days; P = .60).
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Of the 271 patients for whom the injured body part was documented, 123 (45.4%) sustained head/facial injuries; 87 (70.7%) were not wearing a helmet at the time of the injury. The use of a helmet during an ATV crash was not associated statistically with a reduction in the risk of head or facial injury (odds ratio: 0.76; 95% confidence interval: 0.42–1.35).
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DISCUSSION |
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TOPABSTRACTMETHODSRESULTSDISCUSSIONREFERENCES |
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ATV-related injuries continue to cause significant and increasing morbidity and death to youths in the United States.2,4,21,22 Similar to previous studies, our study showed that male patients predominated among those with ATV-related injuries.4,21,23 Injured male patients outnumbered female patients by >3 to 1. White and insured riders also predominated in our study population, although this may reflect the characteristics of patients admitted to the participating hospitals. The mean age of injured children was
11.1 years, similar to the mean ages seen in other pediatric ATV studies.5,21 The mean ISS of 9.2 in this study was lower than those in other pediatric ATV studies, which ranged from 12.3 to 13.6.24,25 The mean length of hospital stay of 4.1 days in this study was comparable to those in other ATV studies.26 This study evaluated whether helmets reduced injury severity among hospitalized ATV riders. Helmets prevent head injuries for subjects riding bicycles and motorcycles.8,10 One study showed that injured pediatric ATV riders had lower ISSs if they were wearing a helmet.5 In that retrospective study, however, patients from only 1 hospital were evaluated and the sample size was small (92 patients, of whom only 22 sustained head or facial injuries). In this study, ISSs and lengths of hospital stays were used to assess injury severity. In contrast to previously published findings, this study failed to show significant differences in ISSs and lengths of hospital stays between helmeted and nonhelmeted ATV riders.
In addition to missing data regarding helmet use (18.9%, 54 of 285 patients) and the exclusion of fatal injuries from analysis, a possible reason why our study failed to show that helmet use reduced ISSs is the fact that the ISS encompasses all injured body regions and not just the head. In this study, as in other ATV studies,4,27,28 orthopedic and soft-tissue injuries were the most common types of injuries. Therefore, the influence of injuries to other body regions on the ISS and length of hospital stay may tend to mask any protective benefit of helmet use with respect to injury to the head.
This study also did not demonstrate a significant reduction in head and facial injuries among helmeted riders, in comparison with nonhelmeted individuals, at the time of an ATV crash. This finding also is in contrast to other pediatric ATV studies.5 However, if all children not known to be wearing a helmet at the time of the crash (n = 54) were considered to be nonhelmeted for analysis, then helmets would prove to be protective against head and facial injuries (P < .05).
In the United States, it is not legal to drive a motor vehicle without a license; in most states, a motor vehicle license cannot be obtained until a person is at least 16 years of age. Children <16 years of age have immature judgment and motor skills, making them less able to maneuver off-road vehicles effectively.29 Children who are not licensed to drive a car should not be allowed to operate ATVs. As evident in this study and similar studies, children <16 years of age continue to sustain significant injuries attributable to ATVs.3,19,20,30 As this study demonstrates, the use of a helmet may not be protective in reducing the significance of injuries sustained by youths <16 years of age while riding an ATV. Therefore, the recommendation of the American Academy of Pediatrics and the American Academy of Orthopedic Surgeons that riders be at least 16 years of age to operate an ATV under any circumstances seems to be the most appropriate intervention to reduce the severity of injuries to youths riding ATVs.6,31 The US Consumer Product Safety Commission recognizes this problem and recently provided advance notice of proposed rulemaking to investigate more completely the problem with respect to youths and ATV usage.32
Another finding in this study was that children injured on ATVs tended to be clustered within the central and southwestern portions of the state. This may be because 2 of Ohio’s major pediatric trauma centers are located in the central and southwestern regions. This may also be because 1 hospital in northeastern Ohio opted not to participate in the study and/or because there is no pediatric trauma center in southeastern Ohio. Therefore, children injured in the most eastern or northern areas of the state might have sought medical care at nonparticipating adult institutions or at trauma centers located in a bordering state, such as Pennsylvania.
This study has several limitations. First, the actual injury problem attributable to ATVs in Ohio likely is underestimated by our data. Only injuries treated at major pediatric trauma centers in the state were reviewed, and 1 of the centers opted not to participate. Also, some older children (14–16 years of age) might have been hospitalized in adult trauma centers, and patients living near the state border might have been treated in neighboring states. In addition, coroner data were not reviewed to determine accurately the number of deaths caused by these vehicles.
Like other retrospective investigations, this study had the limitations of missing data and potential misclassification. Some types of data (eg, protective gear worn, time of injury, and locale of injury) were missing more frequently than other types; in those instances, patients with missing data were excluded from analysis. Also, ATV-related injury rates could not be calculated because of lack of exposure data.
In this study, helmet usage was not demonstrated to be protective against facial and head injuries. However, other studies in the literature showed helmets to be protective. Also, they might have proved to be effective in this study if complete data about helmet usage during ATV collisions were available and if coroner data were available for the state. Therefore, all ATV riders should wear a helmet. Because the majority of patients in this study had health insurance, one strategy to ensure helmet usage could be to increase insurance premiums for riders who do not wear helmets. There is precedent for higher premiums for individuals who engage in high-risk behavior or who do not adopt accepted safety practices, when there is potential for higher health care costs (eg, smoke alarms in homes may reduce home insurance premiums). Alternatively, premiums could be decreased for ATV riders who wear helmets (similar to nonsmokers having reduced premiums). Such an insurance premium disincentive/incentive policy could help promote helmet usage for ATVs.
This study confirms that ATV-related injuries are causing significant morbidity to youths and these injuries have been increasing steadily in recent years in Ohio, consistent with national trends. ATVs are powerful machines, and they are more dangerous than other recreational vehicles available to youths, such as bicycles.27 Parents, manufacturers, public health professionals, health care providers, safety advocates, and policymakers should work together to curtail this escalating injury problem.6 Parents should educate their children about the risks of ATV use, should encourage every state to adopt model legislation, and should follow riding guidelines and recommendations set forth by the American Academy of Pediatrics and others.6,31 As this study shows, helmets are not protective enough to reduce injury severity for youths <16 years of age. Therefore, health care providers, and soon, it is hoped, the Consumer Product Safety Commission, will advocate for legislation to prohibit the use of ATVs by youths <16 years of age.6,32 Finally, injury prevention interventions should be sought in regions of Ohio where ATV-related injuries are more prevalent.
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ACKNOWLEDGMENTS |
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We thank the following individuals for their assistance in collecting and providing data from their regional trauma sites: J. Dobson, Division of Emergency Medicine, Medical College of Ohio (Toledo, OH); T. Krzmarzick, Division of Emergency Medicine, Children’s Medical Center (Dayton, OH); M. Wright, Division of Emergency Medicine, Rainbow Infants’ and Children’s Hospital (Cleveland, OH); H. Marshall, Division of Emergency Medicine, Metro General Hospital (Cleveland, OH); T. Pulio, Division of Pediatrics, Tod Children’s Hospital (Youngstown, OH).
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FOOTNOTES |
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Accepted Dec 28, 2005.
Address correspondence to Michael A. Gittelman, MD, Division of Emergency Medicine, Cincinnati Children’s Hospital Medical Center, 3333 Burnet Ave, ML 2008, Cincinnati, OH 45229. E-mail: gittm1{at}cchmc.org
The authors have indicated they have no financial relationships relevant to this article to disclose.
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PEDIATRICS (ISSN 1098-4275). ©2006 by the American Academy of Pediatrics
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