Commuting by bike in Belgium, the costs of minor accidents

Minor bicycle accidents are defined as “bicycle accidents not involving death or heavily injured persons, implying that possible hospital visits last less than 24 hours”. Statistics about these accidents and related injuries are very poor, because they are mostly not reported to police, hospitals or insurance companies. Yet, they form a major share of all bicycle accidents. Official registrations underestimate the number of minor accidents and do not provide cost data, nor the distance cycled. Therefore related policies are hampered by a lack of accurate data.This paper provides more insight into the importance of minor bicycle accidents and reports the frequency, risk and resulting costs of minor bicycle accidents. Direct costs, including the damage to bike and clothes as well as medical costs and indirect costs such as productivity loss and leisure time lost are calculated. We also estimate intangible costs of pain and psychological suffering and costs for other parties involved in the accident. Data were collected during the SHAPES project using several electronic surveys. The weekly prospective registration that lasted a year, covered 1187 persons that cycled 1,474,978 km. 219 minor bicycle accidents were reported. Resulting in a frequency of 148 minor bicycle accidents per million kilometres. We analyzed the economic costs related to 118 minor bicycle accidents in detail. The average total cost of these accidents is estimated at 841 euro (95% CI: 579–1205) per accident or 0.125 euro per kilometre cycled. Overall, productivity loss is the most important component accounting for 48% of the total cost. Intangible costs, which in past research were mostly neglected, are an important burden related to minor bicycle accidents (27% of the total cost). Even among minor accidents there are important differences in the total cost depending on the severity of the injury.     

Complementing police road-crash records with trauma registry data--an initial evaluation

This paper examines the consistency of hospital and police reporting of outcomes of road traffic crashes using a database of linked police crash reports and trauma registry records. Criteria for inclusion into the trauma registry include trauma-related causes with subsequent stay of more than 24 h or death due to injuries. During the 1997 calendar year there were 497 cases of road-related injuries within the combined trauma registry of Sir Charles Gairdner and Fremantle Hospitals, of which only 82% had matching police records. Linkage rates were associated with gender, injury severity and the number of vehicles involved. Within the road user category, pedestrians were least likely to link. Of the linked records, police classification of injury severity was correct in 78% of cases. Male casualties were more likely to be correctly classified than females, after adjustment for related variables including injury severity. Correct classification of injury by police was also closely related to severity of injury. Identification and targeting of these groups of casualties is vital in refining the road-crash reporting system. Increased crash reporting and availability of data from these two sources will provide road authorities with more reliable measures of injury outcome.     

Measuring transport injuries in a developing country: an application of the capture-recapture method

The purposes of this study are to provide an estimation of the incidence of transport injuries in a defined local community in Nicaragua by using the capture-recapture method, and to compare results using this method when data at different levels of severity are utilized.Two sources of injury data were used to monitor injuries: hospital data (inpatient and outpatient) and traffic police records. Characteristics available for matching included name, age, sex, and date of occurrence. The methodology of capture-recapture was used to estimate the ascertainment degree of both sources of data and the estimate mortality and incidence rates. Estimates were calculated both when all hospital data were taken into account (inpatient and outpatient combined) and when only inpatient records were matched against police records.First, including police records and all hospital data, the mortality and morbidity estimates were 35.5/100000 and 43.7/1000 per year, respectively. Second, when outpatients were excluded from the analysis, the corresponding estimates were 28.6/100000 and 7.5/1000, respectively. In non-fatal cases, the ascertainment-corrected coverage through police records was 2.6% and through hospital surveillance 19.0% when both inpatients and outpatients were included. In fatal cases, the corresponding rates were 56.1 and 22.8%, respectively. The combined data set pointed out pedestrians and cyclists as the main risk groups. Most fatalities were due to head injuries.Our results show that neither police records nor hospital records nor the aggregate database provided acceptable coverage of transport-related injuries. Combining police and hospital data by means of capture-recapture analysis produces more valid estimates, but caution must be given to the issue of severity heterogeneity between the two sources.     

Incidence, severity and correlates of bicycling injuries in a sample of cyclists in Queensland, Australia

Bicycle injuries, particularly those resulting from single bicycle crashes, are underreported in both police and hospital records. Data on cyclist characteristics and crash circumstances are also often lacking. As a result, the ability to develop comprehensive injury prevention policies is hampered. The aim of this study was to examine the incidence, severity, cyclist characteristics, and crash circumstances associated with cycling injuries in a sample of cyclists in Queensland, Australia. A cross-sectional study of Queensland cyclists was conducted in 2009. Respondents (n = 2056) completed an online survey about their cycling experiences, including cycling injuries. Logistic regression modelling was used to examine the associations between demographic and cycling behaviour variables with experiencing cycling injuries in the past year, and, separately, with serious cycling injuries requiring a trip to a hospital. Twenty-seven percent of respondents (n = 545) reported injuries, and 6% (n = 114) reported serious injuries. In multivariable modelling, reporting an injury was more likely for respondents who had cycled <5 years, compared to ≥10 years (p < 0.005); cycled for competition (p = 0.01); or experienced harassment from motor vehicle occupants (p < 0.001). There were no gender differences in injury incidence, and respondents who cycled for transport did not have an increased risk of injury. Reporting a serious injury was more likely for those whose injury involved other road users (p < 0.03). Along with environmental and behavioural approaches for reducing collisions and near-collisions with motor vehicles, interventions that improve the design and maintenance of cycling infrastructure, increase cyclists’ skills, and encourage safe cycling behaviours and bicycle maintenance will also be important for reducing the overall incidence of cycling injuries.     

Bicycle injuries: a matter of mechanism and age

Bicycle riding is a popular form of recreation with positive health and environmental effects. These road users are vulnerable to serious injuries, especially when motor vehicles are involved. The goal of this study was to characterize cyclist-related injuries according to motor vehicle involvement for adults versus children. A retrospective study was carried out using data from 11 trauma centers in the Israeli National Trauma Registry (2001-2007). Injuries were classified according to whether a motor vehicle was involved, and differences in injury characteristics were assessed for adults (18+ years) versus children (1-17 years). A total of 5529 patients were hospitalized for bicycle injuries, of whom 1765 were adults and 3764 were children. Thirty percent (n=1662) of all bicycle injuries involved motor vehicles, although the rate of injuries resulting in hospitalization was 37% among adults and 27% among children. Injury characteristics and hospital resource utilization differed substantially by age group. Cyclists struck by a motor vehicle presented with more severe injuries requiring more hospital resources and resulting in poorer outcomes than those not involved with motor vehicles. The interaction effect between motor vehicle involvement and age was significant for torso injuries and need for medical imaging. We found that injury characteristics, hospital resource utilization and health-related outcomes for bicycle injuries are highly dependent on patient's age and mechanism of injury. Effect modification of motor vehicle involvement by age may in part reflect physicians' attitudes toward pediatric imaging. The risks identified in this study should be used for preparedness and management of trauma hospitalizations from bicycle injuries.     

Characteristics of bicycle crashes in an adolescent population in Flanders (Belgium)

IntroductionIn regions where transportation is mainly motorized, air pollution and traffic congestion are rife. Active transportation such as cycling might be a solution but safety is a major concern. An efficient science based safety policy is needed. The aim of this paper is to analyze in depth the bicycle crash causes and characteristics in an adolescent population (14–18 yr).MethodsBy using questionnaires for self-reported bicycle crashes, bicycle crash data were collected from insurance companies (January 2014–June 2015) and from schools (November 2013–March 2014). Six bicycle crash causes were predefined and possible differences between schools and insurance companies were analyzed.ResultsEighty-six school and 78 insurance registered crashes were analyzed. “Distraction of the cyclist” and “third party crossing a bicycle path failing to see the cyclist” are the main causes of bicycle crashes (both 29%). Bad (maintained) infrastructure accounted for 21% of the crash causes. Bicycle crashes reported at insurance companies needed significantly more medical attention and led to high absenteeism (57% at least one day of absenteeism). Only 21% of the bicycle crashes reported at insurance companies were also reported in the official police database.ConclusionThe human factor was the main cause accounting for 79% of the crashes. Bicycle crashes involving a car accounted for 42% and single bicycle crashes accounted for 31% of the total number of crashes. From the bicycle crashes registered at insurance companies 21% was also registered in official police statistics. A combination of information, education and changing the bicycle specific environment might reduce the consequences of human errors more efficiently.     

Discrepancies in vehicular crash injury reporting: Northeastern Ohio Trauma Study. IV

People injured in motor vehicle traffic crashes were identified from a population-representative incidence sample of hospital emergency department visits. Matched police reports of crashes were sought in official state records of motor vehicle traffic crashes. Of the emergency department cases, 55% had matched police reports. The frequency of matched reports was highest for drivers (74%), people transported to the hospital by emergency vehicle (69%), and those requiring hospital admission (74%). The frequency was lowest for people younger than 16 years (28%), people injured as occupants of vehicles other than passenger cars (24%), medicaid recipients (33%), and nonresidents of the study region (40%). Motor vehicle traffic injuries are undercounted in police-reported statistics. For many groups, police reporting is less than 50% of the cases identified through emergency departments. The likelihood that a case of motor vehicle traffic injury will have a matched police report depends on demographic, social and crash factors as well as on injury severity.     

School regulations governing bicycle helmet use and head injuries among Japanese junior high school students

We examined the effectiveness of school regulations concerning bicycle helmet use in reducing head injuries among student bicycle commuters to junior high schools in the Japanese prefecture of Saitama. This was done by comparing the rates of head injuries and the ratios of head injuries to non-head injuries between junior high schools with and without school regulations concerning helmet use. Bicycle injury data were derived from school insurance records. Information relating to numbers of bicycle commuters and demographics was collected for each school. We identified that the head injury rate was significantly higher in schools that had no regulations governing the use of bicycle helmets (rate ratio 2.97, 95% confidence interval (CI) 1.03-8.56; odds ratio 2.46, 95% CI 0.80-7.60). The observed trend was more prominent in male students than in female students. The actual rate of bicycle injuries did not significantly differ between the schools with and without regulations concerning helmet use. This suggests that students at schools with regulations were no more cautious in riding their bicycles than their counterparts in schools with no regulations, and that there was no significant difference in the traffic environments surrounding each school. Thus implicating that the observed difference in the head injury rate was most accounted for by the presence of school regulations governing helmet use.     

Crash costs in the United States by crash geometry

MAIN OBJECTIVES: This study was conducted to estimate the costs per crash for three police-coded crash severity groupings within 16 selected crash geometry types and within two speed limit categories (or=50 mph). METHODS: We merged previously developed costs per victim by abbreviated injury scale (AIS) score into U.S. crash data files that scored injuries in both the AIS and police-coded severity scales to estimate injury costs, then aggregated the estimates into costs per crash by maximum injury severity. RESULTS: The most costly crashes were non-intersection fatal/disabling injury crashes on a road with a speed limit of 50 miles per hour or higher where multiple vehicles crashed head-on or a single vehicle struck a human (over 1.69 US dollars and 1.16 million US dollars per crash, respectively). The annual cost of police-reported run-off-road collisions, which include both rollovers and object impacts, represented 34% of total costs. CONCLUSIONS: This paper provides cost estimates useful for evaluating roadway countermeasures and for designing vehicles to minimize crash harm. It gives unit costs of crashes by type in the coding system used by the police. The costs are in an appropriate form for economic analysis of countermeasures addressing locally defined problems identified by analyzing police crash reports.     

Road accident statistics: discrepancies between police and hospital data in a French island

In most developed countries, information on road crashes are routinely collected by the police. However, comparison of police records and hospital data underlines a deficit of the number of road accidents in the routine statistics. In La Réunion, a French overseas dependency, an epidemiological study of injuries leading to hospitalisation or deaths has been performed from June 1993 to June 1994. The comparison between hospital data and police records showed that only 37.3% of non-fatally traffic-injured in-patients were recorded by the police. Length of stay in hospital, physician in charge of the first aid, urban place of the crash, type of vehicle involved, day and time of the crash and blood alcohol concentration were significantly associated with the presence in the police file. Police overestimated the severity of the injuries. Police notified 100 deaths on the 115 counted by the study. In France, non-fatally traffic-injured should be followed 30 days to improve quality of police death records. A capture-recapture method was used to estimate the total number of injured people. The capture-recapture method consists in merging information from several sources of notification to determine the real number of cases in the population and the exhaustivity of each source. We estimated that 346 subjects were injured in one month whereas police data recorded only 87 and hospital data 137. This method seems interesting to use in routine after validation when unique personal identifiers are available.     

Statistical adjustment for misclassification of seat belt and alcohol use in the analysis of motor vehicle accident data

The use of seat belts and alcohol is often mis-reported in police motor vehicle accident reports for a number of reasons. To avoid penalties, occupants often over report seat belt use and under report alcohol use. Police officers sometimes fail to account for evidence such as presence of belt burn, condition of belts, odor of alcohol, crash patterns, etc. Biased conclusions result when using misclassified accident data to estimate the effectiveness of seat belts in preventing injuries and reducing medical costs. We investigated the effects of misclassification of seat belt and alcohol use on the odds ratio of injury as well as medical costs. A statistical method and a SAS program were developed to adjust odds ratios of injury and medical cost estimates to account for misclassification of seat belts and alcohol use. The method allowed for incorporation of variables that could affect misclassification of seat belt and alcohol use. We conducted a Monte Carlo simulation and found that when there were large differences between the misclassification rates for major and minor injury, the unadjusted odds ratio could have up to a 90% bias while our adjusted odds ratio was effectively unbiased. To illustrate the method, we estimated the misclassification rates of seat belt and alcohol use by comparing merged police and hospital reports from Nebraska motor vehicle accident data sets (1996-1997) and then evaluated the bias of the odds ratio of injury and medical costs estimates due to misclassification. Our results showed that the bias of the odds ratio of injury and medical costs due to misclassification of seat belts and alcohol use depended both on the amount of misclassification and the reported frequencies. Misclassification about seat belt and alcohol use only slightly biased the unadjusted odds ratio estimates and mean hospital charge, while misclassification resulted in approximately a 69% underestimate of the total medical costs savings due to seatbelts. However, due to the small size of the merged Nebraska police and hospital data set used to estimate misclassification rates, these results are likely somewhat imprecise.     

Misclassification of injury severity among road casualties in police reports

This study aims to evaluate the discordance between police reports of injury severity among road casualties and the length of hospital stay and the Injury Severity Scale (ISS) by linking information from the crash records of the Hong Kong Police with the trauma records of a regional hospital. Sensitivity and specificity analyses suggest that police injury grading diverges noticeably from the definition of a 12-h hospital stay. Police reports overestimate injury severity remarkably. The results of logistic regression indicate that age, the ISS, and the position of the victim significantly determine the likelihood of police injury misclassification. Furthermore, an optimal demarcation point of the length of hospital stay for serious injury is estimated.     

Incidence and costs of bicycle-related traumatic brain injuries in the Netherlands

The main cause of death and serious disability in bicycle accidents is traumatic brain injury (TBI). The aim of this population-based study was to assess the incidence and costs of bicycle-related TBI across various age groups, and in comparison to all bicycle-related injuries, to identify main risk groups for the development of preventive strategies.Data from the National Injury Surveillance System and National Medical Registration were used for all patients with bicycle-related injuries and TBI who visited a Dutch emergency department (ED) between 1998 and 2012. Demographics and national, weighted estimates of injury mechanism, injury severity and costs were analysed per age group. Direct healthcare costs and indirect costs were determined using the incidence-based Dutch Burden of Injury Model.Between 1998 and 2012, the incidence of ED treatments due to bicycle-related TBI strongly increased with 54%, to 43 per 100,000 persons in 2012. However, the incidence of all bicycle-related injuries remained stable, from 444 in 1998 to 456/100,000 in 2012. Incidence of hospital admission increased in both TBI (92%) and all injuries from cycling (71%). Highest increase in incidence of both ED treatments and hospital admissions was seen in adults aged 55+. The injury rate of TBI per kilometre travelled increased (44%) except in children, but decreased (−4%) for all injuries, showing a strong decrease in children (−36%) but an increase in men aged 25+, and women aged 15+. Total costs of bicycle-related TBI were €74.5 million annually. Although bicycle-related TBI accounted for 9% of the incidence of all ED treatments due to cycling, it accounted for 18% of the total costs due to all bicycle-related injuries (€410.7 million). Children and adolescents (aged 0–24) had highest incidence of ED treatments due to bicycle-related injuries. Men in the working population (aged 15–64) had highest indirect costs following injuries from cycling, including TBI. Older cyclists (aged 55+) were identified as main risk group for TBI, as they had highest ED attendance, injury rate, injury severity, admission to hospital or intensive care unit, and costs.Incidence of ED treatments due to cycling are high and often involve TBI, imposing a high burden on individuals and society. Older cyclists aged 55+ were identified as main risk group for TBI to be targeted in preventive strategies, due to their high risk for (serious) injuries and ever-increasing share of ED visits and hospital admissions.     

Cyclist activity and injury risk analysis at signalized intersections: A Bayesian modelling approach

This study proposes a two-equation Bayesian modelling approach to simultaneously study cyclist injury occurrence and bicycle activity at signalized intersections as joint outcomes. This approach deals with the potential presence of endogeneity and unobserved heterogeneities and is used to identify factors associated with both cyclist injuries and volumes. Its application to identify high-risk corridors is also illustrated. Montreal, Quebec, Canada is the application environment, using an extensive inventory of a large sample of signalized intersections containing disaggregate motor-vehicle traffic volumes and bicycle flows, geometric design, traffic control and built environment characteristics in the vicinity of the intersections. Cyclist injury data for the period of 2003–2008 is used in this study. Also, manual bicycle counts were standardized using temporal and weather adjustment factors to obtain average annual daily volumes. Results confirm and quantify the effects of both bicycle and motor-vehicle flows on cyclist injury occurrence. Accordingly, more cyclists at an intersection translate into more cyclist injuries but lower injury rates due to the non-linear association between bicycle volume and injury occurrence. Furthermore, the results emphasize the importance of turning motor-vehicle movements. The presence of bus stops and total crosswalk length increase cyclist injury occurrence whereas the presence of a raised median has the opposite effect. Bicycle activity through intersections was found to increase as employment, number of metro stations, land use mix, area of commercial land use type, length of bicycle facilities and the presence of schools within 50–800 m of the intersection increase. Intersections with three approaches are expected to have fewer cyclists than those with four. Using Bayesian analysis, expected injury frequency and injury rates were estimated for each intersection and used to rank corridors. Corridors with high bicycle volumes, located mainly in the central neighbourhoods of Montreal, have lower risk of injury. These results may reflect the “safety in numbers” hypothesis or cyclist preference towards safer intersections and corridors. Despite these corridors having a lower individual risk, they are nevertheless associated with a greater number of injuries.     

Bicycle accidents and injuries: a pilot study comparing hospital- and police-reported data

Bicycle accident and injury data collected by two different samples of North Carolina hospital emergency rooms during the summers of 1985 and 1986 are examined and compared with state police-reported bicycle accident data for the same time periods. Of the 649 emergency room treated bicyclists, 62% were children aged 5-14 and 70% were male. Nineteen percent of the riders suffered moderate or worse injuries (AIS greater than or equal to 2), and 6% were hospitalized. In contrast, less than half of the police-reported accidents involved riders under 15 years of age, 85% of the riders were male, and two-thirds suffered moderate or worse injury. Whereas virtually all of the police-reported accidents involved a motor vehicle, less than a fifth of the emergency room cases did. Only 10% of the emergency room cases were duplicated on the state accident files. It is estimated that 800 children ages 0-19 are hospitalized annually in North Carolina for bicycle-related injuries, and an additional 13,300 children receive emergency room treatment.     

A comparison of self-reported motor vehicle collision injuries compared with official collision data: an analysis of age and sex trends using the Canadian National Population Health Survey and Transport Canada data

OBJECTIVE: The purpose of this study was to compare the age and sex trends of motor vehicle collision injuries between a nationally representative self-report survey and official police motor vehicle collision report data. To do this, population-based estimates of motor vehicle collision injuries were established using data from the National Population Health Survey (NPHS), a prospective, population-based, longitudinal survey that was compared to Transport Canada's official motor vehicle collision report statistics. METHODS: Aggregated mean data (1994-1996) were compared for seven age groups (15-19, 20-24, 25-34, 35-44, 45-54, 55-64, and 65+) from both data sets. RESULTS: No significant differences were found between males' and females' MVC injuries for any age category in the NPHS. A comparison of the NPHS and Transport Canada data found two small (significant) within-sex differences between the data sets, but overall, the analysis largely revealed similar trends for self-reported injury for all age categories and sex. CONCLUSIONS: The results indicate that the incidence of injuries based on self-report data in a nationally representative sample is similar to official sources of reporting and are thus a valid indicator or motor vehicle collision injury incidence. The results also confirm that injury trends differ from fatality trends.     

Road accident statistics—A comparison of police and hospital information

Studies in Sweden have raised doubts as to the accuracy of road accident statistics in relation to serious and slight injuries. To explore the reliability of British statistics an analysis has been made of a sample of 1200 patients injured in road accidents and attending hospital. These same cases have been traced in the police records on which official statistics are based. All fatal cases were correctly notified but two types of discrepancy occurred among injuries. In a small number of cases re-classification of “serious” and “slight” seemed to be required. A more important discrepancy was that about one-sixth of serious injuries and one third of slight injuries known to the hospital did not appear in the police notifications. This is not surprising in view of the limited scope of compulsory notification. The police mostly know of accidents by the calling of an ambulance or as a result of allegations of traffic infringements. Thus many cases where an ambulance is not called or in which a driver only is injured and no other vehicle is involved, escape notification. Injuries to pedal cyclists are particularly poorly notified. Less than one quarter of those known to the hospital appeared in the official statistics. It is concluded that similar comparisons of hospital and police information should be made elsewhere to confirm whether this sample is representative of the national rate of notification. In the meantime it is suggested that figures for injuries to pedal cyclists and for slight injuries in general should be used with caution.     

Bicycle-related head injury: a study of 86 cases

Within the framework of a bicycle helmet research program, we have set up a database of bicycle accident victims, containing both accident and clinical data. The database consists of a consecutive series of 86 victims of bicycle accidents who underwent a neurosurgical intervention in our hospital between 1990 and 2000. Data were obtained from police files, medical records, computed tomography head scans and a patient questionnaire. In only three victims, the wearing of a helmet was documented. In this study, the head injuries are analysed and the relation between the different types of head injuries and outcome is assessed. Forty-four accidents were collisions with a motor vehicle and 42 accidents were falls. Most impacts occurred at the side (57%) or at the front (27%) of the head. The most frequent injuries were skull fractures (86%) and cerebral contusions (73%). Age was negatively correlated with outcome (P = 0.0002 ) and positively correlated with the number (P = 0.00002) and volume (P = 0.00005) of contusions and the presence of subdural haematomas (P = 0.000001). The injuries with the strongest negative effect on outcome were: subarachnoid haemorrhage (P = 0.000001), multiple (P = 0.000005) or large ( P 0.0007) contusions, subdural haematoma (P = 0.001) and brain swelling (P = 0.002). A significant coexistence of these four injuries was found. We hypothesise that in many patients the contusions may have been the primary injuries of this complex and should therefore be considered as a main injury determining outcome in this study. We believe that such findings may support a rational approach to optimising pedal cyclist head protection.     

The economic burden of injury: Health care and productivity costs of injuries in the Netherlands

BackgroundDetailed information on health care costs and productivity costs for the whole spectrum of injuries is lacking. We measured the total costs of injuries by external-cause, injury groupings, age and sex.MethodInjury patients visiting an Emergency Department in the Netherlands were included. Health service use and work absenteeism were estimated with national database data and a prospective follow-up study. Health care costs (direct costs) and productivity costs (indirect costs) were determined using the incidence-based Dutch Cost of Injury Model.ResultsTotal costs of injuries were €3.5 billion annually (€210/capita and €4300/patient); €2.0 billion healthcare costs and €1.5 billion productivity costs. Home and leisure injury subcategory falls caused 41% of total costs. Traffic injury was prominent in the 15–54 age group, mainly due to bicycle injuries. Sports injuries, in special football/soccer injuries, resulted in high costs in the 15–24 age group. Although costs per patient were comparable between males and females, health care costs were higher in females, whereas males have more than twice as high productivity costs. Health care costs were highest for hip fractures (€20,000/patient). Extremity fractures had high costs due to high incidences and high productivity costs per patient.ConclusionOur detailed cost model identified known risk groups, such as elderly females with hip fractures resulting from falls, as well as less obvious important high risk groups, such as young children falling from furniture, young males who sustained football/soccer injuries and bicycle injuries among all ages. This information is essential to assess additional priority areas for prevention.     

Validity of using linked hospital and police traffic crash records to analyse motorcycle injury crash characteristics

Linking hospital discharge and police traffic crash records has been used to provide information on causes and outcomes for hospitalised traffic crash cases. Motorcyclists are particularly vulnerable to injury in a traffic crash, but no published linkage studies have reported in detail on this road user group. The present study examined motorcycle traffic crash injury cases in New Zealand in 2000–2004 by probabilistically linking national hospital discharge records with police traffic crash reports. Injury cases had to have spent at least one night in hospital before being discharged and were defined as serious or moderate based on their International Classification of Disease Injury Severity Scores (ICISS). Despite a robust linkage process, only 46% of cases could be linked to a police record; 60% of the serious injuries and 41% of the moderate. The low linkage was most likely due to under-reporting of crashes to or by the police. While moderate injury cases were expected to be under-reported, the level of under-reporting of cases with serious threat-to-life injuries is concerning. To assess whether the linked dataset could provide valid information on the crash circumstances and injury outcomes of hospitalised motorcycle crash cases, the characteristics of the linked and unlinked hospital discharge cases were compared using chi-square tests and multivariate logistic regression. Serious injury cases were less likely to be linked if only one vehicle was involved, or the injured riders and passengers were younger than 20 years or spent less than one week in hospital. For moderate injury cases, there were also differences in linkage by injured body region and crash month. While these discrepancies need to taken into consideration when interpreting results, the linked hospital-police dataset has the potential to provide insights into motorcycle crash circumstances and outcomes not otherwise obtainable.