Comparison of the number of pedestrian and cyclist injuries captured in police data compared with health service utilisation data in Toronto, Canada 2016-2021

INTRODUCTION

Pedestrian and cyclist injuries represent a preventable burden to Canadians. Police-reported collision data include information on where such collisions occur but under-report the number of collisions. The primary objective of this study was to compare the number of police-reported collisions with emergency department (ED) visits and hospitalisations in Toronto, Canada.

METHODS

Police-reported collisions were provided by Toronto Police Services (TPS). Data included the location of the collision, approximate victim age and whether the pedestrian or cyclist was killed or seriously injured. Health services data included ED visits in the National Ambulatory Care Reporting System and hospitalisations from the Discharge Abstract Database using ICD-10 codes for pedestrian and cycling injuries. Data were compared from 2016 to 2021.

RESULTS

Injuries reported in the health service data were higher than those reported in the TPS for cyclists and pedestrians. The discrepancy was the largest for cyclists treated in the ED, with TPS capturing 7.9% of all cycling injuries. Cyclist injuries not involving a motor vehicle have increased since the start of the pandemic (from 3629 in 2019 to 5459 in 2020 for ED visits and from 251 in 2019 to 430 for hospital admissions).

IMPLICATIONS

While police-reported data are important, it under-reports the burden. There have been increases in cyclist collisions not involving motor vehicles and decreases in pedestrian injuries since the start of the pandemic. The results suggest that using police data alone when planning for road safety is inadequate, and that linkage with other health service data is essential.

Blame attribution analysis of police motor vehicle collision reports involving child bicyclists

BACKGROUND

Injuries resulting from collisions between a bicyclist and driver are preventable and have high economic, personal and societal costs. Studying the language choices used by police officers to describe factors responsible for child bicyclist-motor vehicle collisions may help shift prevention efforts away from vulnerable road users to motorists and the environment. The overall aim was to investigate how police officers attribute blame in child (≤18 years) bicycle-motor vehicle collision scenarios.

METHODS

A document analysis approach was used to analyse Alberta Transportation police collision reports from Calgary and Edmonton (2016-2017). Collision reports were categorised by the research team according to perceived blame (child, driver, both, neither, unsure). Content analysis was then used to examine police officer language choices. A narrative thematic analysis of the individual, behavioural, structural and environmental factors leading to collision blame was then conducted.

RESULTS

Of 171 police collision reports included, child bicyclists were perceived to be at fault in 78 reports (45.6%) and adult drivers were perceived at fault in 85 reports (49.7%). Child bicyclists were portrayed through language choices as being irresponsible and irrational, leading to interactions with drivers and collisions. Risk perception issues were also mentioned frequently in relation to poor decisions made by child bicyclists. Most police officer reports discussed road user behaviours, and children were frequently blamed for collisions.

CONCLUSIONS

This work provides an opportunity to re-examine perceptions of factors related to motor vehicle and child bicyclist collisions with a view to prevention.

Is higher school neighbourhood Walk Score associated with greater child pedestrian safety near schools?

Walk Score is a common index used to estimate how suitable the built environment is for walking. Although Walk Score has been extensively validated as a measure of walkability and walking, there are limited studies examining whether commonly used constructs of walkability are associated with traffic safety in children. This study examined the association between Walk Score and child pedestrian injury controlling for observed walking exposure in school zones in Calgary, Toronto and Montreal, Canada. Results indicate that a higher Walk Score was associated with more child pedestrian injuries in all three cities, even after controlling for walking exposure. School travel planning should consider established individual pedestrian collision risk and individual factors rather than assuming a highly walkable environment is also a safe pedestrian environment.

Child pedestrian and cyclist injuries, and the built and social environment across Canadian cities: the Child Active Transportation Safety and the Environment Study (CHASE)

Introduction

Traffic injury is a leading and preventable cause of child death and disability, with child pedestrians and cyclists particularly vulnerable. Examining built environment correlates of child pedestrian and cyclist motor vehicle collisions (PCMVC) in different settings is needed to promote an evidence-based approach to road safety.

Methods

We conducted a cross-sectional study across multiple urban/suburban environments in Canada (Calgary, Toronto, Montreal, Laval, Peel Region). All public elementary schools were included (n=1030). We examined the role of land use/social environments, road environments and traffic safety interventions on the rates of child PCMVC within 1000 m of schools. Multivariable negative binomial regression was conducted for all cities and by individual city. In a subset of schools (n=389), we examined associations when controlling for active school transportation (AST).

Results

Mean PCMVC rate per school ranged from 0.13 collisions/year in Peel to 0.35 in Montreal. Child PCMVC were correlated with land use, social and road environments and traffic safety interventions. In fully adjusted models, social and land use features remained the most important correlates. New immigrant population had the largest positive association with child PCMVC (incidence rate ratio (IRR): 1.26, 95% CI 1.06 to 1.50), while old housing (pre-1960) density was most protective (IRR: 0.83, 95% CI 0.77 to 0.90). AST was associated with PCMVC, but it had no effect on the relationships between PCMVC and other social/environmental correlates.

Conclusion

The built environment and social factors influence rates of child PCMVC. Opportunities to reduce child PCMVC exist through modifications to city design and road environments and implementing traffic safety interventions.

Pilot study to evaluate school safety zone built environment interventions

BACKGROUND

School safety zones were created in 2017 under the City of Toronto's Vision Zero Road Safety Plan. This pilot study examined the effect of built environment interventions on driver speeds, active school transportation (AST) and dangerous driving.

METHODS

Interventions were implemented at 34 schools and 45 matched controls (2017-2019). Drivers travelling over the speed limit of >30 km/hour and 85th percentile speeds were measured using pneumatic speed tubes at school frontages. Observers examined AST and dangerous driving at school arrival times. Repeated measures beta and multiple regression analyses were used to study the intervention effects.

RESULTS

Most schools had posted speed limits of 40 km/hour (58%) or ≥50 km/hour (23%). A decrease in drivers travelling over the speed limit was observed at intervention schools post-intervention (from 44% to 40%; OR 0.79, 95% CI 0.66 to 0.96). Seventy-one per cent of drivers travelled >30 km/hour and the 85th percentile speed was 47 km/hour at intervention schools, with no change in either postintervention. There were no changes in speed metrics in the controls. AST increased by 5% (OR 1.22, 95% CI 0.97 to 1.54) at intervention schools. Reductions in dangerous driving were observed at all schools.

CONCLUSIONS

Posted speed limits were >30 km/hour at most schools and high proportions of drivers were travelling above the speed limits. There were reductions in drivers exceeding the speed limit and in dangerous driving, and modest increased AST post intervention. Bolder interventions to slow traffic are required to effectively reduce speeding around schools, which may increase safe AST.

Methodological considerations in MVC epidemiological research

Background

The global burden of MVC injuries and deaths among vulnerable road users, has led to the implementation of prevention programmes and policies at the local and national level. MVC epidemiological research is key to quantifying MVC burden, identifying risk factors and evaluating interventions. There are, however, several methodological considerations in MVC epidemiological research.

Methods

This manuscript collates and describes methodological considerations in MVC epidemiological research, using examples drawn from published studies, with a focus on the vulnerable road user population of children and adolescents.

Results

Methodological considerations in MVC epidemiological research include the availability and quality of data to measure counts and calculate event rates and challenges in evaluation related to study design, measurement and statistical analysis. Recommendations include innovative data collection (eg, naturalistic design, stepped-wedge clinical trials), combining data sources for a more comprehensive representation of collision events, and the use of machine learning/artificial intelligence for large data sets.

Conclusions

MVC epidemiological research can be challenging at all levels: data capture and quality, study design, measurement and analysis. Addressing these challenges using innovative data collection and analysis methods is required.

State-of-the-art review: preventing child and youth pedestrian motor vehicle collisions: critical issues and future directions

Aim

To undertake a comprehensive review of the best available evidence related to risk factors for child pedestrian motor vehicle collision (PMVC), as well as identification of established and emerging prevention strategies.

Methods

Articles on risk factors were identified through a search of English language publications listed in Medline, Embase, Transport, SafetyLit, Web of Science, CINHAL, Scopus and PsycINFO within the last 30 years (~1989 onwards).

Results

This state-of-the-art review uses the road safety Safe System approach as a new lens to examine three risk factor domains affecting child pedestrian safety (built environment, drivers and vehicles) and four cross-cutting critical issues (reliable collision and exposure data, evaluation of interventions, evidence-based policy and intersectoral collaboration).

Conclusions

Research conducted over the past 30 years has reported extensively on child PMVC risk factors. The challenge facing us now is how to move these findings into action and intervene to reduce the child PMVC injury and fatality rates worldwide.

Recent trends in child and youth emergency department visits because of pedestrian motor vehicle collisions by socioeconomic status in Ontario, Canada

BACKGROUND

Children in lower-income households have higher injury rates. Trends in emergency department (ED) visits by children 0-19 years because of pedestrian motor vehicle collisions (PMVCs) in Ontario, Canada (2008-2015) by socioeconomic status were examined.

METHODS

PMVC ED data were obtained from the Institute for Clinical Evaluative Sciences for children age 0-19 years over the period 2008-2015. Age-adjusted rates were calculated using Ontario census data. Household income quintiles were determined from the Registered Persons Database. Poisson regression was used to model ED visit rates by year, age and income quintile.

RESULTS

The frequency of child PMVC ED visits in Ontario decreased from 1562 in 2008 to 1281 in 2015. Age-adjusted rates were unchanged over time (IRR 1.00, 95% CI 0.99 to 1.00); however, rate disparities by income status persisted with an IRR of 0.52 (0.50 to 0.55) comparing the highest with the lowest income level.

CONCLUSIONS

Exposure to traffic may play a role in rate disparities by income status in child PMVC; however, less safe traffic environments in lower income areas may also be strong contributors. These findings highlight the potential impact of roadway safety modifications in lower income areas to mitigate disparities in injury rates by socioeconomic status.

Spatial distribution of roadway environment features related to child pedestrian safety by census tract income in Toronto, Canada

BACKGROUND

Investments in traffic calming infrastructure and other street design features can enhance pedestrian safety as well as contribute to the 'walkability' of neighbourhoods. Pedestrian-motor vehicle collisions (PMVCs) in urban areas, however, remain common and occur more frequently in lower income neighbourhoods. While risk and protective features of roadways related to PMVC have been identified, little research exists examining the distribution of roadway environment features. This study examined the relationship between roadway environment features related to child pedestrian safety and census tract income status in Toronto.

METHODS

Spatial cluster detection based on 2006 census tract data identified low-income and high-income census tract clusters in Toronto. Police-reported PMVC data involving children between the ages of 5 and 14 years were mapped using geographical information system. Also mapped were roadway environment features (densities of speed humps, crossing guards, local roads, one-way streets and missing sidewalks). Multivariate logistic regression was used to examine the relationship between roadway environment features (independent variables) and cluster income status (dependent variable), controlling for child census tract population.

RESULTS

There were significantly fewer speed humps and local roads in low-income versus high-income clusters. Child PMVC rates were 5.4 times higher in low-income versus high-income clusters.

CONCLUSION

Socioeconomic inequities in the distribution of roadway environment features related to child pedestrian safety have policy and process implications related to the safety of child pedestrians in urban neighbourhoods.

Spatial distribution of pedestrian-motor vehicle collisions before and after pedestrian countdown signal installation in Toronto, Canada

BACKGROUND

Pedestrian countdown signals (PCS) have been installed in many cities over the last 15 years. Few studies have evaluated the effectiveness of PCS on pedestrian motor vehicle collisions (PMVC). This exploratory study compared the spatial patterns of collisions pre and post PCS installation at PCS intersections and intersections or roadways without PCS in Toronto, and examined differences by age.

METHODS

PCS were installed at the majority of Toronto intersections from 2007 to 2009. Spatial patterns were compared between 4 years of police-reported PMVC prior to PCS installation to 4 years post installation at 1864 intersections. The spatial distribution of PMVC was estimated using kernel density estimates and simple point patterns examined changes in spatial patterns overall and stratified by age. Areas of higher or lower point density pre to post installation were identified.

RESULTS

There were 14 911 PMVC included in the analysis. There was an overall reduction in PMVC post PCS installation at both PCS locations and non-PCS locations, with a greater reduction at non-PCS locations (22% vs 1%). There was an increase in PMVC involving adults (5%) and older adults (9%) at PCS locations after installation, with increased adult PMVC concentrated downtown, and older adult increases occurring throughout the city following no spatial pattern. There was a reduction in children's PMVC at both PCS and non-PCS locations, with greater reductions at non-PCS locations (35% vs 48%).

CONCLUSIONS

Results suggest that the effects of PCS on PMVC may vary by age and location, illustrating the usefulness of exploratory spatial data analysis approaches in road safety. The age and location effects need to be understood in order to consistently improve pedestrian mobility and safety using PCS.

Reducing resource utilization during non-operative treatment of pediatric proximal humerus fractures

INTRODUCTION

The majority of proximal humeral fractures in the skeletally immature are treated non-operatively. Operative indications vary but are largely based on degree of displacement. Non-union is rare. Non-operatively treated fractures are typically monitored radiographically to assess healing.

HYPOTHESIS

We hypothesize that the decision to treat fractures operatively is made at the time of first imaging and that follow-up X-rays do not lead to a change in management.

MATERIAL AND METHODS

We retrospectively reviewed the records of 239 patients treated for proximal humerus fractures over a 5-year period. There were 225 who were treated non-operatively. Records were reviewed for the number of clinic visits and radiographs, as well as any change to operative management based on follow-up X-rays.

RESULTS

The primary outcome of the study was the proportion of proximal humerus fractures, initially treated non-operatively, for which displacement or angulation on follow-up radiographs led to a change to operative treatment. Secondary outcomes were the number of follow-up radiographs obtained after the initial diagnosis and initiation of non-operative treatment. Of the 225 patients that were initially managed non-operatively, only 1 patient required subsequent surgical management. This patient underwent a proximal humerus epiphysiodesis 365 days from injury after development of a partial growth arrest. The mean number of fracture clinic visits for patients managed non-operatively was 2.67 (±1.24). The mean number of radiology department visits and radiographs obtained was 3.57 (±1.44) and 8.36 (±3.89) respectively. No clinical or radiographic non-unions were identified in these patients. No patients suffered a refracture during the review period.

DISCUSSION

This study shows that of the 239 uncomplicated pediatric proximal humerus fractures treated at our hospital over a 5-year period, only 1 had a change in treatment plan, from non-operative to operative, based on follow-up radiographs. These data suggest that non-operative treatment of proximal humerus fractures seldom results in displacement that warrants operative intervention. Moreover, they suggest that there is little utility to the routine use of postoperative radiographs in follow-up of these patients.

STUDY DESIGN

Retrospective case series.

LEVEL OF EVIDENCE

IV.

Children, automobile restraints and injuries

Injuries are the most common cause of death for Canadians aged one to 18 years, and 50% of injury deaths in this age group involve an automobile. Evidence suggests that 71% reduction in deaths and a 67% reduction in injuries can be achieved when child safety seats are used properly. This article reviews the recommended restraints for children by weight group and describes the proper position for children. Detailed case examples of car crashes are described to illustrate the dangers of incorrectly used or no restraint.

A social problem index for Canada

OBJECTIVE

To construct an index that represents the general level of social problems among Canadian provinces and territories.

METHOD

Factor weights were used to combine provincial and territorial rates for homicide, attempted murder, assault, sexual assault, robbery, divorce, suicide, and alcoholism into a single Social Problem Index.

RESULTS

The resulting index demonstrated strong positive intercorrelations among its factors across provinces. That is, provinces that showed high rates on one factor tended to show high rates on the others as well. The validity of the Social Problem Index is demonstrated by its positive correlation with an independent measure of the likelihood of having experienced personal trauma.

CONCLUSIONS

The robust nature and apparent validity of the Social Problem Index suggest that it can be well used for needs assessments and theoretical studies and as a feedback mechanism to national, provincial, and community leaders on the social problem status of their particular jurisdictions.

Limited dorsiflexion predisposes to injuries of the ankle in children

Injuries to the ankle are common in children. We investigated whether decreased dorsiflexion predisposes to such fractures and sprains. Passive dorsiflexion in children with ankle injuries was compared with that in a control group of patients with a normal ankle. The uninjured side was examined to determine flexibility in those patients with ankle injuries. In 82, the mean dorsiflexion was 5.7 degrees with the knee extended and 11.2 degrees with the knee flexed. In 85 controls, the mean dorsiflexion was 12.8 degrees with the knee extended and 21.5 degrees with the knee flexed (p < 0.001, Student's t-test). There was a strong association between decreased ankle dorsiflexion and injury in children. A flexible triceps surae appeared to absorb energy and protect the bone and ligaments, while stiffness predisposed to injury. We suggest that children with tight calf muscles should undergo a regimen of stretching exercises to improve their flexibility.

Cervical spondylolysis in children: is it posttraumatic?

Cervical spondylolysis is a rare defect of unknown etiology. Five cases of cervical spondylolysis as well as two cases of fractures of the pedicles of C2 in infants are presented. Comparison of the cases suggests that a fracture at birth or in infancy may be the cause of some cases of cervical spondylolysis.

Reduction in osteomyelitis and septic arthritis related to Haemophilus influenzae type B vaccination

This retrospective cohort study compares organisms responsible for septic arthritis and osteomyelitis before and after Haemophilus influenzae type b vaccination. Before vaccination, Haemophilus influenzae type b was responsible for 5% of culture positive osteomyelitis and 41% of culture positive septic arthritis. Since the administration of the conjugated vaccine PRP-T began in 1992, no case of osteomyelitis or septic arthritis has been caused by Haemophilus influenzae type b (p < 0.005, t test). Vaccination has succeeded in eliminating Haemophilus influenzae type b as an infective agent in hematogenous septic arthritis and osteomyelitis. Current empirical antibiotic therapy for hematogenous septic arthritis and osteomyelitis need only cover gram-positive agents in vaccinated infants and children of all age groups.

Low molecular weight heparin decreases proximal and distal deep venous thrombosis following total knee arthroplasty. A meta-analysis of randomized trials

OBJECTIVES

To assess the efficacy and safety of low molecular weight heparin (LMWH) as deep venous thrombosis (DVT) prophylaxis following total knee arthroplasty.

DATA SOURCES

Medline 1986 to June 1997, Embase, and manufacturers were used to identify randomized controlled trials.

REVIEW METHODS

Trials included were randomized studies of LMWH with routine radiological screening for DVT. Placebo or active controls were included. Two reviewers independently screened trials for inclusion, and assessed their quality. Pooled relative risk estimates of DVT and proximal DVT rates were calculated using a DerSimonian and Laird random effects model. Sensitivity of the results to the type of control used and the quality of the trial was assessed.

RESULTS

The relative risk of DVT for a patient given LMWH is 0.73 (95% CI 0.66 to 0.80) when compared with patients treated with adjusted dose heparin or warfarin controls. The relative risk for proximal DVT is 0.58 (95% CI 0.38 to 0.90). The relative risk of pulmonary emboli in the LMWH group was 0.55 (95% C.I. 0.20 to 1.57). No excess of bleeding was recorded in the LMWH group.

CONCLUSIONS

Low molecular weight heparin is more efficacious than either adjusted dose heparin or adjusted dose warfarin, when used to prevent DVT and proximal DVT following total knee arthroplasty.