Injury Prevention 1995; 1: 256-261 INJURY CLASSIC Bicycle ownership, use, and injury patterns among elementary schoolchildren Julian A Waller Abstract Patterns of bicycle ownership and injury were studied over a four month period among over 6000 schoolchildren. Two thirds of the bikes owned were standard style and one third high rise. Boys more often had high rise bikes. Slightly over 2% of bike owners are injured annually, but no differences were found according to bike style either in injury rate or severity. Bike borrowing and riding double were common factors in the injury events. Injury from spokes and loss of control because of loose handlebars were identified as problems resulting from -product design. (Pediatrics 1971; 47: 1042-1050) Keywords: bicycles, injury, accidents, risk taking behavior. Although the widespread use of bicycles goes back at least a century, and although they are owned by nearly all children and many adults, there has been a striking dearth of serious study of the ownership and use of bicycles by young children, and of the injuries resulting there- from. A recent change in bicycle usage has made such study imperative. In the mid-1 960s a new style of bicycle - the high rise bike - began to appear on the market. This bike has a small front wheel, elongated handlebar projec- ting vertically instead of horizontally as with standard bikes, and an elongated, 'banana' seat. Some also have a 'sissy' or balancing bar behind the seat projecting up from 2 in to 2 ft above the level of the seat. The new bike presumably is more maneuverable and permits children to play a wider range of games. This new style has rapidly captured the market. However, in 1968 Howell,' based on his clinical experience, reported a marked increase both in the frequency and the severity of injuries to bike riders since the introduction of the high rise bike on the market. These injuries, he noted, resulted from falls to children who could easily control standard model bikes but who lost control while riding these bikes. In England the Royal Society of Prevention of Accidents also expressed concern about the safety of the new style of bike and referred to it as 'gimmicky.'2 The present study grew out of a concern that the injury potential of this new product - just as of any new product - should be evaluated. It is quite conceivable that high rise bikes do represent a new hazard as described above. It is equally possible that the new style, on really careful evaluation, would turn out not to be a problem. Furthermore, if one bike is associated with greater frequency or severity of injury, or both, this may be the result of the style of bike, the fact that it is used by more active or daring children, that the daily number of hours of use per child is greater for this style of bike (in the case of greater frequency of injury), or a combination of these factors. Method The study was limited to bicycle owners and persons injured on bikes in the Greater Burl- ington, Vermont, area who were between the ages of 3 and 12 years, since almost all high rise bikes are owned by persons in this age range. Four separate steps were involved in the study. (1) During the 1969 registration of bicycles by the South Burlington Police Department, questionnaires were given to 380 consecutive individuals of the 1092 persons who registered bikes. Fifty nine per cent of the questionnaires were returned, and 67% of these indicated that the bike was owned by a person aged 12 or younger. The questionnaires contained in- formation about bike style, duration of owner- ship, age at which the child began riding a bicycle, and medically treated injuries involv- ing bikes. (2) During October and November, 1969, an interviewer visited grades kindergarten through 6 in all elementary schools in the Burlington, South Burlington, and Burlington Catholic school systems to obtain information about bike ownership and frequency of bike use after dark. All children were shown, first a photograph of a standard bike, next one of a high rise bike, and finally one of a high rise bike with long 'sissy' bar. A tally was made of the proportion in each grade and sex category that reported owning each type of bike, or reported owning two bikes of different types simul- taneously. These figures were corrected to take into consideration children who were absent on the day the survey was made. It was assumed that the pattern of bike ownership did not change appreciably between the summer months, when patient interviews, described below, were begun and mid-November when the school survey was completed. In addition, it was important to determine if owners of different styles of bicycles use their This paper is thefifth in a series of Injury Classic. Our goal is to reprint one such paper in each issue to initiate newcomers to the field to these old, often quoted, and important contributions. As many are difficult tofind, it should help all of us to have a copy at hand. Your suggestions about future articles are welcome. Write to the editor with details ofyour favourite, most quoted paper. Department of Community Medicine, University of Vermont College of Medicine, Burlington, Vermont 05401, USA This paper first appeared in Pediatrics (1971; 47: 1042 - 50) and is reproduced by permission of Pediatrics. 256 on May 31, 2020 by guest. Protected by copyright. http://injuryprevention.bmj.com/ Inj Prev: first published as 10.1136/ip.1.4.256 on 1 December 1995. Downloaded from
Transcript
Injury Prevention 1995; 1: 256-261
INJURY CLASSIC
Bicycle ownership, use, and injury patterns amongelementary schoolchildren
Julian A Waller
AbstractPatterns of bicycle ownership and injurywere studied over a four month periodamong over 6000 schoolchildren. Twothirds of the bikes owned were standardstyle and one third high rise. Boys moreoften had high rise bikes. Slightly over 2%of bike owners are injured annually, butno differences were found according tobike style either in injury rate or severity.Bike borrowing and riding double werecommon factors in the injury events.Injury from spokes and loss of controlbecause of loose handlebars wereidentified as problems resulting from-product design.(Pediatrics 1971; 47: 1042-1050)
Although the widespread use of bicycles goesback at least a century, and although they areowned by nearly all children and many adults,there has been a striking dearth of serious studyof the ownership and use of bicycles by youngchildren, and of the injuries resulting there-from. A recent change in bicycle usage hasmade such study imperative. In the mid-1 960sa new style of bicycle - the high rise bike -began to appear on the market. This bike has asmall front wheel, elongated handlebar projec-ting vertically instead of horizontally as withstandard bikes, and an elongated, 'banana' seat.Some also have a 'sissy' or balancing bar behindthe seat projecting up from 2 in to 2 ft above thelevel of the seat. The new bike presumably ismore maneuverable and permits children toplay a wider range of games. This new style hasrapidly captured the market.However, in 1968 Howell,' based on his
clinical experience, reported a marked increaseboth in the frequency and the severity ofinjuries to bike riders since the introduction ofthe high rise bike on the market. These injuries,he noted, resulted from falls to children whocould easily control standard model bikes butwho lost control while riding these bikes. InEngland the Royal Society of Prevention ofAccidents also expressed concern about thesafety of the new style of bike and referred to itas 'gimmicky.'2The present study grew out of a concern that
the injury potential of this new product- justas ofany new product- should be evaluated. It
is quite conceivable that high rise bikes dorepresent a new hazard as described above. It isequally possible that the new style, on reallycareful evaluation, would turn out not to be aproblem. Furthermore, ifone bike is associatedwith greater frequency or severity of injury, orboth, this may be the result of the style of bike,the fact that it is used by more active or daringchildren, that the daily number of hours of useper child is greater for this style of bike (in thecase of greater frequency of injury), or acombination of these factors.
MethodThe study was limited to bicycle owners andpersons injured on bikes in the Greater Burl-ington, Vermont, area who were between theages of 3 and 12 years, since almost all high risebikes are owned by persons in this age range.Four separate steps were involved in the study.
(1) During the 1969 registration of bicyclesby the South Burlington Police Department,questionnaires were given to 380 consecutiveindividuals of the 1092 persons who registeredbikes. Fifty nine per cent of the questionnaireswere returned, and 67% of these indicated thatthe bike was owned by a person aged 12 oryounger. The questionnaires contained in-formation about bike style, duration of owner-ship, age at which the child began riding abicycle, and medically treated injuries involv-ing bikes.
(2) During October and November, 1969, aninterviewer visited grades kindergartenthrough 6 in all elementary schools in theBurlington, South Burlington, and BurlingtonCatholic school systems to obtain informationabout bike ownership and frequency ofbike useafter dark. All children were shown, first aphotograph of a standard bike, next one of ahigh rise bike, and finally one of a high rise bikewith long 'sissy' bar. A tally was made of theproportion in each grade and sex category thatreported owning each type of bike, or reportedowning two bikes of different types simul-taneously. These figures were corrected to takeinto consideration children who were absent onthe day the survey was made. It was assumedthat the pattern of bike ownership did notchange appreciably between the summermonths, when patient interviews, describedbelow, were begun and mid-November whenthe school survey was completed.
In addition, it was important to determine ifowners of different styles of bicycles use their
This paper is thefifth in aseries of Injury Classic.Our goal is to reprint onesuch paper in each issue toinitiate newcomers to thefield to these old, oftenquoted, and importantcontributions. As many aredifficult tofind, it shouldhelp all of us to have a copyat hand. Your suggestionsaboutfuture articles arewelcome. Write to theeditor with details ofyourfavourite, most quotedpaper.
Department ofCommunity Medicine,University ofVermontCollege ofMedicine,Burlington, Vermont05401, USA
This paper first appeared inPediatrics (1971; 47:1042 - 50) and is reproducedby permission of Pediatrics.
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*In this and subsequent tables, total per cents may not equal 100 because of rounding out ofdecimal places. Per cents are rounded to the nearest decimal place if N > 100, and to the nearestwhole number if N < 100.
bikes with similar frequency. Therefore, obser-vations were made by the interviewer in neigh-borhoods in which injuries had occurred todetermine the prevalence of standard and highrise bicycles being ridden by children at thetimes she made interview visits describedbelow. A total of426 children were so observedover a period offour months between the hoursof 9.45 am and 8.00 pm.
(3) Follow up was carried out of all childrenages 3 through 12 who had medically treatedinjuries while on moving bicycles between June15 and October 14, 1969. Injuries were exc-luded in which children fell against or other-wise injured themselves with stationary ornon-moving bicycles. All ofthe injuries involv-ing bicycles were identified through the treat-ment records of the emergency room at theMedical Center Hospital of Vermont. Thishospital provides almost all of the emergencyroom care for the communities included in thestudy. In addition, all trauma patients to behospitalized are admitted through theemergency room.A telephone survey of physicians in the area
revealed that they either refer all patients withsuch injuries to the emergency room (in thecase of the pediatricians) or treat them therethemselves (in the case of the surgeons andgeneral practitioners) and then give follow upcare in their offices. Only rarely is primary caregiven in the physician's office. No attempt wasmade to determine the frequency of primarytreatment in dentists' offices, and it is possiblethat a very few injuries were missed which wereseen only in dentists' offices.
Table 2 Wheel size offirst bicycle owned according toage of learning among children involved in bicycle injuriesand comparison group matchedfor age and sex
Wheel size Age of learning (years)(inches) 5 o n 7
Basic information was obtained from thehospital records about the nature of the eventand the injuries. The mother of each injuredchild was then visited by a trained interviewerin order to obtain further information about thecircumstances of the event, type of bicycle, an
estimate of level of activity and risk takingbehavior by the child relative to other childrenthe same age and sex, and parental interest andparticipation in various sports. If the injuredchild was a passenger on the bike, the inform-ation about the event, riding experience,activity and parental interests was obtainedfrom the mother of the child who actually wasin control of the bike. All such mothers inter-viewed seemed quite knowledgeable about theevent itself even though their own childrenhadn't been injured.A total of 107 relevant injuries were
identified in the four month period throughhospital records. Interviews were completedwith the mothers (or in one case, the babysitterwho took care of the child after the event)concerning 104 of these. Two additionalmothers refused to be interviewed, and followup was impossible of a third case because thefamily had left town.
(4) In the fourth step a child the same age,sex, and neighbor.L.Lo)d of residence was mat-ched with the injured child, or with the driver,where the injured child was a passenger. Thematch was obtained by asking the mother of theinjured child (or of the driver) at the com-
pletion of the interview to name the child livingnearest who was the same age and sex as theinjured child (or the driver). All such matcheswere within a year or two ofthe age sought. Themother of the comparison child was inter-viewed with reference to her own child, was
asked all of the questions asked about theinjured child except those that were irrelevantfor the comparison sample, because theyinvolved the injury event. A total of 99 suchinterviews were completed. Two additionalmothers refused to be interviewed, and threefurther children were not matched because theinjured person was a child, but the operator ofthe bike was above age 12.
In the analysis, injury rates were computedusing injuries from Burlington and South Burl-ington only, since denominator informationwas available only from these two com-
munities. All injuries, no matter what the townof residence in the Burlington area, were usedin comparing relative proportions among chil-dren who had been injured (or had been incontrol of a bike at the time a passenger was
injured) and children of same age, sex, andneighborhood who owned bikes but had notbeen injured on them during the four months ofthe study. Where appropriate, data were
analyzed by means of the x2 test to determinethe statistical significance of differencesobserved.
ResultsPATTERNS OF OWNERSHIPA total of 4698 children were surveyed in theBurlington and Burlington Catholic SchoolSystems and 1364 in the South Burlington
School System. By the time they reach kinder-garten two thirds of children own bikes.Ownership rises during the first two grades andbecomes stable from grades 2 through 6, with80 to 900% of children owning bikes. Overall,one third of bikes owned are high rise style.Ownership of high rise bikes is much greateramong boys than among girls (table 1). Thesurvey of the prevalence of bike use accordingto style suggests that both styles of bicycle are
used about equally often by their owners.For children who still owned their first bikes,
the age at which they learned to ride was
compared with the wheel size of the bike. Thisis shown in table 2.
Significantly more high rise bikes were lessthan one year old, and owners ofhigh rise bikeswho had been injured were significantly morelikely (p< 0.05) to have a new bike than were
owners of such bikes in the comparison group.Among bike owners in injury events, 70% ofstandard bikes and 43% of high rise bikes werefirst bikes, whereas 47% and 32% respectivelywere first bikes among comparison groupowners with standard and high rise styles. Bothgroups, of course, were similar in age, and boththe injury and the comparison groups respec-tively learned to ride two wheeled bikes at meanages of 5 8 and 5 9 years.
PATTERNS OF BICYCLE USEWhen the school survey was carried out child-ren were asked ifthey ever rode their bikes afterdark. Table 3 shows the proportion ofboys andgirls in each community who state they ridetheir bikes after dark.
Seventy eight per cent of respondents to theregistration questionnaire report that the bikeis ridden by only one child, with no differenceobserved between standard and high rise styles.The older the child, the more likely is he toshare it with others. Thus, 19% of children age6 or under, 21% of those age 7 through 9, and29% of children age 10 through 12 were
reported to share their bikes.
INJURY RATESFour month injury rates per 1000 bike owners
were determined for Burlington and SouthBurlington since denominator informationabout ownership was available only for thesetwo communities. The four month injury ratesappear in table 4. Actually, the total bike ridingseason in this area extends from early April to
Table 3 Per cent by schoolgrade ofboys andgirls whoride bicycles after dark in Burlington and SouthBurlington
*Owners of two bikes of different styles were considered to useeach bike for one half of their riding.
late November; therefore, the injury ratesreported can reasonably be estimated to be onehalf the annual injury rates. This, slightly over2% of bicycle owners in this age range can beexpected to have medically treated injuries eachyear involving moving bicycles.Boys had significantly higher injury rates per
1000 users than did girls, a pattern that is quiteconsistent with the greater occurrence of allinjuries among boys. It is not clear whether inthis case boys have higher injury rates becausethey use their bikes more often than girls,because they use them in different ways, or acombination of these reasons.
Injury rates for children ages 5 through 9were somewhat, but not significantly higherthan for those ages 10 through 12. Surprisingly,however, the rate among 5 year olds, virtuallyall ofwhom could be considered to be learners,was no higher than for those age 8 or 9, almostall ofwhom already had several years of ridingexperience. No injuries were observed among 4year olds from Burlington or South Burlington,although almost 15% of children learn to rideby this age. It may be that children who areathletically most competent learn to ride at theyoungest age, a question considered later, orthat greater riding skill at ages 8 and 9 is offsetby more 'daredevil' riding behavior. It is alsopossible that real differences were missedbecause of the small sample size of injuries ineach age group, although if the phenomenon ofgreater risk at certain ages were strong enough(for example, a twofold increase) it should haveshown up despite the smallness of the sample.
Injury rates per 1000 owners of high risebikes were somewhat higher than for owners ofstandard bikes. These differences were notsignificant, however, for either sex. In contrastto the determination of injury rates, the com-parison of bike styles of the injured and theuninjured serves to identify retrospectivelywhether one style was overexpressed in injurieswhen used by persons of similar age, sex, and
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Bicycle ownership, use, and injury patterns among elementary schoolchildren
area of residence. Sixty one per cent of bikesinvolved in injuries were of standard style incomparison with 52% of bikes owned by unin-jured neighbors matched for age and sex. Theseproportions, which were based upon all 104injuries instead of only those from Burlingtonand South Burlington, again do not suggestthat high rise bikes were overrepresented ininjury events. The consistency in resultsbetween these two methods suggests that in factno difference exists between the two types ofbike.
TYPES OF INJURYThe types of injuries incurred on the two stylesof bicycles were compared. Two thirds of thechildren injured had only abrasions, con-tusions, or lacerations. About 20% of injurieswere fractures, and 500 concussions. Nodifference was observed between bike styles indistribution of severity of injury. However,220% of children on high rise bikes, but only10% on standard bikes, had injury to the headonly (p = 0-07).
Contact with the ground was responsible forthe majority of injuries. Most really seriouslyinjuries- that is, concussions and fractures-occurred from contact with objects other thanthe bike itself. However, the frequency ofinjury from bicycle wheels was unanticipated,14 persons having had injury from this source.The major reason for this becomes apparentwhen the mechanism of the event is examined.In 18 of the 104 injury events the bicyclecarried both a driver and a passenger, and thepassenger was injured in 17 of these. Contactwith the wheel was the cause of the injury innine of these injuries, and contact with thedrive chain was the cause in a 10th case. In theremaining wheel injuries, the rider's foot slip-ped off the pedal and into the spokes.
MECHANISM OF EVENTAll injuries occurred either during full daylightor, rarely, at dusk. The circumstances involvedin the event were compared for standard andhigh rise bikes and are shown in table 5.Although a wide range of circumstancesappears to be involved, two major differencescan be observed between events involvingstandard and high rise bikes. A significantlylarger proportion of injuries on standard bikeswere involved in collisions with automobiles,while horseplay was a factor in a significantlylarger proportion of events on high rise bikes.Although the exact numbers have not beendocumented, it is however relevant that severalmothers spontaneously commented that thehandlebars on their children's bikes were looseand that this may have contributed to loss ofcontrol. Fewer than 5% of all injuries involvedriding 'no hands'.
Thirty seven per cent ofthe injuries occurredto individuals who were not riding their ownbikes. In 34% of these 38 cases the individualwas riding someone else's high rise, and in 66°!ohe was riding someone else's standard bike.Forty one per cent of injuries to persons on
Table 5 Circumstances leading to event among injuriesto children with standard and high rise bicycles
Type of bicycle
Circumstances of event Standard High rise
Lost control, no apparent reason 500 1000Lost control while attempting to turn 5 7Lost control while attempting to stop 8 5Hit obstruction 19 15Horseplay 13 29Distracted 10 2Foot caught in bike 11 10Part of bike broke 3 2Rode too close to stationary object 8 10Panic in presence of car or other 8 2
their own bikes involved high rise style. Child-ren who owned high rise bikes were about aslikely to borrow standard bikes as were thosewho owned standard bikes to borrow the highrise style.As noted earlier, passengers were present in
about one injury out of every six. Some form ofloss of control was a factor in 370% of injuriesinvolving passengers, and another 32%involved a foot getting caught. In contrast, lossof control was a factor in 26% of injurieswithout a passenger, and feet were caught inonly 60%. Horseplay was a factor in 110% ofevents with passengers and 21% involvingunaccompanied drivers.Over three quarters of injuries involving
passengers occurred on borrowed bikes. Inmany cases the owners of these bikes hadpermitted friends or siblings to borrow thebikes and were sitting behind them aspassengers. Thus the driver not only had tohandle a bike with which he may have beenrelatively unfamiliar, but he also had to do sowhile carrying additional weight. The endresult of this arrangement commonly was thatthe owner got injured.
Seventy three injuries occurred to personsriding on smooth roads, 14 on dirt or gravelroads, and 17 in fields, on paths, or other placeswithout roads. In 18oo of injuries on smoothroads or on non-road surfaces, but 570o ofthose on gravel or dirt roads, the mechanism ofthe event was loss of control while attemptingto turn or because an obstacle in the road wasstruck.
CHARACTERISTICS OF BICYCLE OWNERS ANDTHEIR PARENTSIt was hypothesized that children in the injurygroup more often would be reported as exces-sively active and daring, and would tend to havesportsminded parents. A further hypothesiswas that active, risk taking children with activeparents would be more likely to own high risebikes.
In response to questions about activity level,mothers in both the injury and comparisongroups rated their children equally. There is anobvious skewing towards reporting by mothersthat their children - whether boys or girls -are more active than others the same age and
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sex. Put in other words, most mothers are suretheir children are the world's most active, orpretty nearly so. However, apparently they candistinguish between amount ofactivity and thatwhich involves risk taking, because in both theinjury and comparison groups, a fairly normaldistribution curve of level of daring wasreported.
Children who own high rise bikes, whetherin the injury or comparison group, more oftenare reported by their mothers to be very activein comparison to children who own standardbikes.No differences were observed in level of
activity or daring, or in style of bike ownedaccording to the parents' interest in sports.Activity scale did seen to be related to age atwhich children learn to ride (O 10 <p < 0-15).Thus, children who were rated less active thantheir peers comprise respectively 40%, 5%, 8 QO0and 170% ofthose who learned to ride at age 4 orunder, 5, 6, and 7 or older. No such differenceswere observed according to daring scale.Where both parents are sports oriented,
children learn to ride a bike at an early age (5 oryounger), whereas if neither parent is interest-ed in sports they often don't learn until aged 7or later (p< 0 05). If only one parent is inter-ested in sports, the age at which the child learnsis greater than if both parents are interested,but a bit earlier than if neither is interested.
DiscussionAs is documented in this report, the recentchanges in the form of the high rise style so farhave made themselves felt much more amongboys than among girls, despite the fact that,judging by frequency of ownership, the bicycleitself is an equally popular form of recreationfor both sexes.Some of the observations of this study were
disturbing, others reassuring. Among those inthe former category is the small, but excessive,number of children who have bikes apparentlytoo large for them to handle properly. Forexample, among children who learned to ride atage 6 and who still had their first bikes, 22%had bicycles with 26" wheels.A second point of concern is the relatively
large proportion of children who state that theyride their bikes at night, despite the rarity ofoperational lights on bikes this investigator hasobserved at night. It was indeed a surprise,therefore, to find that all injuries occurredduring daylight hours, an observation some-what at variance with a recent study of col-lisions between bicycles and automobiles inNorth Carolina.3 The absence of injuries afterdark may perhaps be attributed to the fact thatthe present study was not limited to collisionswith automobiles, and in fact included ratherfew of these events. Also, the study coveredonly half of the bike riding season, includingmonths with long hours of daylight. Further-more, although many children mayoccasionally ride after dark, the nighttimeexposure still may comprise only a very smallproportion of the total hours of exposure.
Regarding the injury pattern, there does not
appear to be any strong evidence in this studythat high rise bikes are more hazardous than thestandard style, either in greater frequency orseverity ofinjury despite concern on theoreticalgrounds that such hazard exists. The totalsample of injuries admittedly is small, so thatmodest but real differences might conceivablynot appear to be statistically significant. Thefact that there is such consistency between twodifferent methods for comparing rates, and nodifferences in severity, however, suggests thatin fact the new style is not more hazardous,despite a contrary conclusion by the NationalCommission on Product Safety4 based entirelyon anecdotes and engineering theory ratherthan epidemiologic data.Two possible areas for stylistic change which
could improve the safety record of the productdo deserve consideration. The first results fromthe frequency of injury to legs and feet bywheels, especially the spokes. A recent paperhas indicated that many of these injuries aremore serious than originally estimated uponinitial examination at time of injury.5
Admittedly, a large proportion of theseinjuries result from what an adult would callmisuse of the bike, such as riding double,borrowing bikes, speeding downhill, and soforth. The frequency of such activitiesassociated with the injuries observed is one ofthe important conclusions of this study. Moreimportant, however, the prime consumers ofthe product - that is, children who are stilllearning to balance caution and action -apparently do not commonly consider suchbehavior to represent misuse. As long as aproduct is made for a consumer, it must bereasonably responsive to the types of demandsthat can be anticipated will be made by theconsumer. And, according to a recent study ofbicycle games played by children, the demandsmay be quite varied.6 With this in mind, itappears reasonable to examine the potentialsand implications of other less damagingmechanisms that can substitute for spokes inmaintaining the integrity of the wheel, or thatcan reduce the hazard of spokes when theybreak.The second area for stylistic change is the
handlebar and the fork within which it rests.Mothers spontaneously mentioned severaltimes that the handlebars were loose, a situationthat would not occur ifthe surfaces at which thebars and fork are held were flattened instead ofbeing perfectly round. This would require onlyminimal changes in the manufacturing process,certainly far more minimal than the changesrequired to design and market the high risestyle. In this investigator's experience, it isquite easy for handlebars and forks to loosenand get out of alignment during the process ofnormal, condoned use of bikes. Such looseningcan be anticipated to occur much more often ifthe bike is used for 'wheelies' (riding momen-tarily on the rear wheel only), a maneuver thatis accomplished more easily and therefore morefrequently with the high rise bike.Adding to the likelihood that bike parts will
loosen is the fact that many, if not most bikes-as well as other toys- offered for sale in recent
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Bicycle ownership, use, and injury patterns among elementary schoolchildren
years come unassembled and must be puttogether by an army of mechanicallyuneducated fathers, often with inadequateequipment for the task at hand. Originally,when unassembled toys were sold, they tendedto be accompanied by 'throw away' tools of theappropriate sizes, Even this assistance is nolonger the rule. It is perfectly clear that risinglabor costs and profit squeeze are largely res-ponsible for these changes that put moreburden on the consumer. It is also clear,however, that the unwanted consequences goconsiderably beyond the harried look thatmany fathers have the day after they purchase anew toy for their children.
Children who learn to ride at an early age aremostly likely to be active children, presumablywith more advanced neuromuscular develop-ment. Furthermore, they more often haveparents who are intensely interested in sportsand are likely to supervise their learningendeavors. This may explain why injury ratesare similar during the four youngest years ofbicycle ownership, again assuming that realdifferences haven't been overlooked because ofsmall sample size. Parents, in general, seem touse reasonable judgement in permitting theirchildren to ride only when they appear to becapable of doing so without undue hazard.
SummaryA study was made of bicycle ownership amongover 6000 children ages 5 through 12 in Burl-ington and South Burlington, Vermont, and ofall medically treated injuries over a four monthperiod involving moving bicycles to children inthis age range who lived in Burlington andsurrounding communities. A total of 104 suchinjuries were studied. The injured childrenwere compared with uninjured neighbors mat-ched for neighborhood, age, and sex.Ownership of two wheeled bicycles rises
rapidly beginning at about age 4, until it
stabilizes by age 7, with eight or nine out ofevery 10 children owning bicycles. Children,both of whose parents are interested in sports,are much more likely to learn to ride at age 5 oryounger, while those with neither parent inter-ested in sports more often learn at age 7 orolder. Boys are more likely to own high risebicycles than are girls. Overall, two thirds ofbicycles owned are standard style and one thirdare high rise. The high rise bicycles tend to bemore recent purchases.
Slightly over 2% of bike owners are injuredon moving bicycles each year, with boys havingsignificantly higher injury rates than girls.Injury rates are fairly stable for ages 5 through9 and slightly lower during ages 10 through 12.Thirteen per cent of injuries- usually involv-ing two persons on the bicycle- resulted fromcontact with the wheel. Thirty seven per cent ofthe injuries involved persons on borrowedbicycles.High rise bicycles do not appear to be more
hazardous than standard bicycles. However,modification of bicycle wheels to reduceinjurious contact with spokes and ofhandlebarsto reduce the frequency of loosening appearswarranted.
Joanne Gobrecht, Elinor Rosenstein, Judy Bromberg, and DrElbert B Whorton of the Department of Community Medicinecollaborated in various phases of the study. Appreciation isexpressed to the Medical Center Hospital ofVermont, the staffsof the Burlington and South Burlington School Departments,the Burlington Catholic elementary schools, and the SouthBurlington Police Department for assistance in this project.
1 Howell TR. Accidents and those bizarre bicycles. Pediatrics1968; 42: 214.
2 Bannister ET. (Royal Society for the Prevention ofAccidents), Letter to National Commission on ProductSafety, May 8, 1969.
3 Waller PF, Reinfurt DW. Bicycles: an analysis ofaccidents inNorth Carolina. Chapel Hill, North Carolina: UniversityofNorth Carolina Highway Safety Research Center 1969.
4 Final Report of the National Commission on Product Safety.Washington DC, US Government Printing Office, June1970.
