Severity of urban cycling injuries and the relationship with personal, trip, route and crash characteristics: analyses using four severity metrics.

OBJECTIVE: To examine the relationship between cycling injury severity and personal, trip, route and crash characteristics. METHODS: Data from a previous study of injury risk, conducted in Toronto and Vancouver, Canada, were used to classify injury severity using four metrics: (1) did not continue trip by bike; (2) transported to hospital by ambulance; (3) admitted to hospital; and (4) Canadian Triage and Acuity Scale (CTAS). Multiple logistic regression was used to examine associations with personal, trip, route and crash characteristics. RESULTS: Of 683 adults injured while cycling, 528 did not continue their trip by bike, 251 were transported by ambulance and 60 were admitted to hospital for further treatment. Treatment urgencies included 75 as CTAS=1 or 2 (most medically urgent), 284 as CTAS=3, and 320 as CTAS=4 or 5 (least medically urgent). Older age and collision with a motor vehicle were consistently associated with increased severity in all four metrics and statistically significant in three each (both variables with ambulance transport and CTAS; age with hospital admission; and motor vehicle collision with did not continue by bike). Other factors were consistently associated with more severe injuries, but statistically significant in one metric each: downhill grades; higher motor vehicle speeds; sidewalks (these significant for ambulance transport); multiuse paths and local streets (both significant for hospital admission). CONCLUSIONS: In two of Canada's largest cities, about one-third of the bicycle crashes were collisions with motor vehicles and the resulting injuries were more severe than in other crash circumstances, underscoring the importance of separating cyclists from motor vehicle traffic. Our results also suggest that bicycling injury severity and injury risk would be reduced on facilities that minimise slopes, have lower vehicle speeds, and that are designed for bicycling rather than shared with pedestrians.

Bicycling crash circumstances vary by route type: a cross-sectional analysis.

BACKGROUND: Widely varying crash circumstances have been reported for bicycling injuries, likely because of differing bicycling populations and environments. We used data from the Bicyclists' Injuries and the Cycling Environment Study in Vancouver and Toronto, Canada, to describe the crash circumstances of people injured while cycling for utilitarian and leisure purposes. We examined the association of crash circumstances with route type. METHODS: Adult cyclists injured and treated in a hospital emergency department described their crash circumstances. These were classified into major categories (collision vs. fall, motor vehicle involved vs. not) and subcategories. The distribution of circumstances was tallied for each of 14 route types defined in an earlier analysis. Ratios of observed vs. expected were tallied for each circumstance and route type combination. RESULTS: Of 690 crashes, 683 could be characterized for this analysis. Most (74%) were collisions. Collisions included those with motor vehicles (34%), streetcar (tram) or train tracks (14%), other surface features (10%), infrastructure (10%), and pedestrians, cyclists, or animals (6%). The remainder of the crashes were falls (26%), many as a result of collision avoidance manoeuvres. Motor vehicles were involved directly or indirectly with 48% of crashes. Crash circumstances were distributed differently by route type, for example, collisions with motor vehicles, including "doorings", were overrepresented on major streets with parked cars. Collisions involving streetcar tracks were overrepresented on major streets. Collisions involving infrastructure (curbs, posts, bollards, street furniture) were overrepresented on multiuse paths and bike paths. CONCLUSIONS: These data supplement our previous analyses of relative risks by route type by indicating the types of crashes that occur on each route type. This information can guide municipal engineers and planners towards improvements that would make cycling safer.

Effectiveness of an educational video on concussion knowledge in minor league hockey players: a cluster randomised controlled trial.

BACKGROUND: With the heightened awareness of concussions in all sports, the development and implementation of effective prevention strategies are necessary. Education has been advocated as an effective injury prevention intervention. PURPOSE: To examine the effectiveness of the 'Smart Hockey: More Safety, More Fun' video on knowledge transfer among minor league hockey players. STUDY DESIGN: Cluster-randomised controlled trial. METHODS: A total of 267 participants from two age divisions and competitive levels were assigned to either a video or no-video group. The video was shown (or not shown) to the entire team as a result of random assignment. To evaluate the effectiveness of the educational video, questionnaires specific to concussion knowledge and players' attitudes and behaviours were completed. RESULTS: There was a significant increase in the players' concussion knowledge scores immediately following exposure to the video (F(1,103)=27.00, p<0.001). However, concussion knowledge at 2 months was not significantly different between the video and no-video groups, after controlling for prior knowledge level, age and competitive level (F(1,115)=0.41, p=0.523). Similarly, players' attitudes and behaviour scores at 2 months did not differ between groups (F(1,115)=0.41, p=0.507). CONCLUSIONS: We were able to show that a single viewing of an educational video in hockey could immediately improve knowledge about concussion but that this effect was transient and lost at 2-month follow-up. Future prevention endeavours in hockey and other sports should attempt to incorporate strategies and modalities to enhance knowledge retention.

Comparing the effects of infrastructure on bicycling injury at intersections and non-intersections using a case-crossover design.

BACKGROUND: This study examined the impact of transportation infrastructure at intersection and non-intersection locations on bicycling injury risk. METHODS: In Vancouver and Toronto, we studied adult cyclists who were injured and treated at a hospital emergency department. A case-crossover design compared the infrastructure of injury and control sites within each injured bicyclist's route. Intersection injury sites (N=210) were compared to randomly selected intersection control sites (N=272). Non-intersection injury sites (N=478) were compared to randomly selected non-intersection control sites (N=801). RESULTS: At intersections, the types of routes meeting and the intersection design influenced safety. Intersections of two local streets (no demarcated traffic lanes) had approximately one-fifth the risk (adjusted OR 0.19, 95% CI 0.05 to 0.66) of intersections of two major streets (more than two traffic lanes). Motor vehicle speeds less than 30 km/h also reduced risk (adjusted OR 0.52, 95% CI 0.29 to 0.92). Traffic circles (small roundabouts) on local streets increased the risk of these otherwise safe intersections (adjusted OR 7.98, 95% CI 1.79 to 35.6). At non-intersection locations, very low risks were found for cycle tracks (bike lanes physically separated from motor vehicle traffic; adjusted OR 0.05, 95% CI 0.01 to 0.59) and local streets with diverters that reduce motor vehicle traffic (adjusted OR 0.04, 95% CI 0.003 to 0.60). Downhill grades increased risks at both intersections and non-intersections. CONCLUSIONS: These results provide guidance for transportation planners and engineers: at local street intersections, traditional stops are safer than traffic circles, and at non-intersections, cycle tracks alongside major streets and traffic diversion from local streets are safer than no bicycle infrastructure.

Route infrastructure and the risk of injuries to bicyclists: a case-crossover study.

OBJECTIVES: We compared cycling injury risks of 14 route types and other route infrastructure features. METHODS: We recruited 690 city residents injured while cycling in Toronto or Vancouver, Canada. A case-crossover design compared route infrastructure at each injury site to that of a randomly selected control site from the same trip. RESULTS: Of 14 route types, cycle tracks had the lowest risk (adjusted odds ratio [OR] = 0.11; 95% confidence interval [CI] = 0.02, 0.54), about one ninth the risk of the reference: major streets with parked cars and no bike infrastructure. Risks on major streets were lower without parked cars (adjusted OR = 0.63; 95% CI = 0.41, 0.96) and with bike lanes (adjusted OR = 0.54; 95% CI = 0.29, 1.01). Local streets also had lower risks (adjusted OR = 0.51; 95% CI = 0.31, 0.84). Other infrastructure characteristics were associated with increased risks: streetcar or train tracks (adjusted OR = 3.0; 95% CI = 1.8, 5.1), downhill grades (adjusted OR = 2.3; 95% CI = 1.7, 3.1), and construction (adjusted OR = 1.9; 95% CI = 1.3, 2.9). CONCLUSIONS: The lower risks on quiet streets and with bike-specific infrastructure along busy streets support the route-design approach used in many northern European countries. Transportation infrastructure with lower bicycling injury risks merits public health support to reduce injuries and promote cycling.

Personal and trip characteristics associated with safety equipment use by injured adult bicyclists: a cross-sectional study.

BACKGROUND: The aim of this study was to estimate use of helmets, lights, and visible clothing among cyclists and to examine trip and personal characteristics associated with their use. METHODS: Using data from a study of transportation infrastructure and injuries to 690 adult cyclists in Toronto and Vancouver, Canada, we examined the proportion who used bike lights, conspicuous clothing on the torso, and helmets on their injury trip. Multiple logistic regression was used to examine associations between personal and trip characteristics and each type of safety equipment. RESULTS: Bike lights were the least frequently used (20% of all trips) although they were used on 77% of trips at night. Conspicuous clothing (white, yellow, orange, red) was worn on 33% of trips. Helmets were used on 69% of trips, 76% in Vancouver where adult helmet use is required by law and 59% in Toronto where it is not. Factors positively associated with bike light use included night, dawn and dusk trips, poor weather conditions, weekday trips, male sex, and helmet use. Factors positively associated with conspicuous clothing use included good weather conditions, older age, and more frequent cycling. Factors positively associated with helmet use included bike light use, longer trip distances, hybrid bike type, not using alcohol in the 6 hours prior to the trip, female sex, older age, higher income, and higher education. CONCLUSIONS: In two of Canada's largest cities, helmets were the most widely used safety equipment. Measures to increase use of visibility aids on both daytime and night-time cycling trips may help prevent crashes.

Safe cycling: how do risk perceptions compare with observed risk?

OBJECTIVE: Safety concerns deter cycling. The Bicyclists' Injuries and the Cycling Environment (BICE) study quantified the injury risk associated with 14 route types, from off-road paths to major streets. However, when it comes to injury risk, there may be discordance between empirical evidence and perceptions. If so, even if protective infrastructure is built people may not feel safe enough to cycle. This paper reports on the relationship between perceived and observed injury risk. METHODS: The BICE study is a case-crossover study that recruited 690 injured adult cyclists who visited emergency departments in Toronto and Vancouver. Observed risk was calculated by comparing route types at the injury sites with those at randomly selected control sites along the same route. The perceived risk was the mean response of study participants to the question "How safe do you think this site was for cyclists on that trip?", with responses scored from +1 (very safe) to -1 (very dangerous). Perceived risk scores were only calculated for non-injury control sites, to reduce bias by the injury event. RESULTS: The route type with the greatest perceived risk was major streets with shared lanes and no parked cars (mean score = -0.21, 95% confidence interval [CI]: -0.54-0.11), followed by major streets without bicycle infrastructure (-0.07, CI -0.14-0.00). The safest perceived routes were paved multi-use paths (0.66, CI 0.43-0.89), residential streets (0.44, CI 0.37-0.51), bike paths (0.42, CI 0.25-0.60) and residential streets marked as bike routes with traffic calming (0.41, CI 0.32-0.51). Most route types that were perceived as higher risk were found to be so in our injury study; similarly, most route types perceived as safer were also found to be so. Discrepancies were observed for cycle tracks (perceived as less safe than observed) and for multiuse paths (perceived as safer than observed). CONCLUSIONS: Route choices and decisions to cycle are affected by perceptions of safety, and we found that perceptions usually corresponded with observed safety. However, perceptions about certain separated route types did not align well. Education programs and social media may be ways to ensure that public perceptions of route safety reflect the evidence.

Using geographical information systems mapping to identify areas presenting high risk for traumatic brain injury.

BACKGROUND: The aim of this study is to show how geographical information systems (GIS) can be used to track and compare hospitalization rates for traumatic brain injury (TBI) over time and across a large geographical area using population based data. RESULTS & DISCUSSION: Data on TBI hospitalizations, and geographic and demographic variables, came from the Ontario Trauma Registry Minimum Data Set for the fiscal years 1993-1994 and 2001-2002. Various visualization techniques, exploratory data analysis and spatial analysis were employed to map and analyze these data. Both the raw and standardized rates by age/gender of the geographical unit were studied. Data analyses revealed persistent high rates of hospitalization for TBI resulting from any injury mechanism between two time periods in specific geographic locations. CONCLUSIONS: This study shows how geographic information systems can be successfully used to investigate hospitalizaton rates for traumatic brain injury using a range of tools and techniques; findings can be used for local planning of both injury prevention and post discharge services, including rehabilitation.

The Bicyclists' Injuries and the Cycling Environment study: a protocol to tackle methodological issues facing studies of bicycling safety.

BACKGROUND AND AIMS: Bicycling may be less appealing in parts of the world where cycling is less safe. Differences between jurisdictions suggest route design is key to improving safety and increasing ridership. Previous studies faced difficulties in effectively assessing denominators for risk calculations and controlling confounding. This paper describes the advantages of the case-crossover design of the Bicyclists' Injuries and the Cycling Environment study to address these challenges to observational studies of cycling safety. METHODS: Injured cyclists were recruited from the emergency departments of five hospitals in Vancouver and Toronto, Canada. In 18 months, 690 participants were successfully recruited and interviewed. Each participant was interviewed to map the route of their injury trip, identify the injury site and select two control sites at random from the same route. Infrastructural characteristics at each study site were scored by site observers who were blinded as to whether sites were crash or comparison sites. Analyses will compare infrastructural variables between case and control sites with conditional logistic regression. DISCUSSION: This study presents a novel application of the case-crossover design to the evaluation of relationships between infrastructure and cycling safety while controlling confounders and exposure to risk. It is hoped that the value of this method and the efficiency of the recruitment process will encourage replication in other locations, to expand the range of cycling infrastructure compared and to facilitate evidence-based cycling infrastructure choices that can make cycling safer and more appealing.

Age group differences in collision risk.

INTRODUCTION: The purpose of the current study was to examine differences in factors associated with self-reported collision involvement of three age groups of drivers based on a large representative sample of Ontario adults. METHOD: This study was based on data from the CAMH Monitor, an ongoing cross-sectional telephone survey of Ontario adults 18 years and older from 2002 to 2005. Three age groups were examined: 18-34 (n=1,294), 35-54 (n=2,428), and 55+ (n=1,576). For each age group sample, a logistic regression analysis was conducted of self-reported collision involvement in the last 12 months by risk factor measures of driving exposure (kilometers driven in a typical week, driving is stressful, and driving on busy roads), consuming five or more drinks of alcohol on one occasion (past 12 months), cannabis use (lifetime, and past 12 months), and driving after drinking among drinkers (past 12 months), controlling for demographics (gender, region, income, and marital status). RESULTS: The study identified differences in factors associated with self-reported collision involvement of the three age groups of adult drivers. The logistic regression model for the youngest group revealed that drivers who reported that driving was stressful at least some of the time, drank five or more drinks on an occasion, and drove after drinking had an increased risk of collision involvement. For the middle age group, those who reported using cannabis in the last 12 months had significantly increased odds of reporting collision involvement. None of the risk factor measures showed significant associations with collision risk for older drivers (aged 55+). IMPACT: The results suggest potential areas for intervention and new directions for future research.

The long-term safety and efficacy of opioids: a survey of 84 selected patients with intractable chronic noncancer pain.

BACKGROUND: The use of opioids for chronic noncancer pain (CNCP) remains controversial. Despite a number of randomized controlled trials showing efficacy and safety in the short term, long-term data are limited. OBJECTIVE: To survey a selected cohort of patients with intractable CNCP with regard to long-term efficacy and safety of opioids. METHODS: The present study reports long-term results from a survey of 84 patients with CNCP. The majority of patients had neuropathic pain, were treated with opioids and were followed every three months for a median of 8.4 years. Outcomes examined were pain severity, adverse effects, pain relief, satisfaction, mood, problematic opioid use, tolerance, physical dependency, functional status, health-related quality of life, immune status, sexual function, morbidity and mortality. Measures included a numerical rating scale, the Hospital Anxiety and Depression Scale, Brief Pain Inventory interference scale, Pain Disability Index and Short-Form Health Survey 12, version 2. RESULTS AND CONCLUSIONS: Both long- and short-acting opioids were reported to be effective, with few significant long-term adverse effects in many subjects in the present selected cohort. The majority of patients reported at least 50% or greater pain relief and a moderate improvement in disability. Functional status and health-related quality of life scores were not severely affected. Problematic opioid use, tolerance and serious adverse effects, including constipation, were not major issues. The authors emphasize that the results obtained in the present selected group may not be generalizable to all CNCP patients in whom opioids are being initiated.

Patterns of urban violent injury: a spatio-temporal analysis.

OBJECTIVES: Injury related to violent acts is a problem in every society. Although some authors have examined the geography of violent crime, few have focused on the spatio-temporal patterns of violent injury and none have used an ambulance dataset to explore the spatial characteristics of injury. The purpose of this study was to describe the combined spatial and temporal characteristics of violent injury in a large urban centre. METHODOLOGY/PRINCIPAL FINDINGS: Using a geomatics framework and geographic information systems software, we studied 4,587 ambulance dispatches and 10,693 emergency room admissions for violent injury occurrences among adults (aged 18-64) in Toronto, Canada, during 2002 and 2004, using population-based datasets. We created kernel density and choropleth maps for 24-hour periods and four-hour daily time periods and compared location of ambulance dispatches and patient residences with local land use and socioeconomic characteristics. We used multivariate regressions to control for confounding factors. We found the locations of violent injury and the residence locations of those injured were both closely related to each other and clearly clustered in certain parts of the city characterised by high numbers of bars, social housing units, and homeless shelters, as well as lower household incomes. The night and early morning showed a distinctive peak in injuries and a shift in the location of injuries to a "nightlife" district. The locational pattern of patient residences remained unchanged during those times. CONCLUSIONS/SIGNIFICANCE: Our results demonstrate that there is a distinctive spatio-temporal pattern in violent injury reflected in the ambulance data. People injured in this urban centre more commonly live in areas of social deprivation. During the day, locations of injury and locations of residences are similar. However, later at night, the injury location of highest density shifts to a "nightlife" district, whereas the residence locations of those most at risk of injury do not change.

Development of the BACKIE questionnaire: a measure of children's behaviors, attitudes, cognitions, knowledge, and injury experiences.

OBJECTIVE: The objective of this study was to develop a standardized questionnaire (BACKIE) that would assess the Behaviors (B), Attitudes (A), Cognitions (C), Knowledge (K), and Injury Experiences (IE) that elementary-school children possess pertaining to seven types of injuries, including: falls; motor vehicle collisions; burns; drowning; choking/suffocation; poisoning; and bicycle/pedestrian injuries. METHODS: Over 500 children in grades two through seven completed the questionnaire, with a sub-sample repeating it two months later to assess test-retest reliability of the measure. RESULTS: Psychometric assessment of the instrument revealed acceptable internal and test-retest reliabilities and results of a Confirmatory Factor Analysis provided support for the hypothesized factor structure. CONCLUSION: Having a psychometrically sound measure that allows one to assess attitudes, cognitions, and knowledge is an essential first step to exploring the relative influence of these factors on children's risk and safety practices.

Evaluating web-based static, animated and interactive maps for injury prevention.

Public health planning can benefit from visual exploration and analysis of geospatial data. Maps and geovisualization tools must be developed with the user-group in mind. User-needs assessment and usability testing are crucial elements in the iterative process of map design and implementation. This study presents the results of a usability test of static, animated and interactive maps of injury rates and socio-demographic determinants of injury by a sample of potential end-users in Toronto, Canada. The results of the user-testing suggest that different map types are useful for different purposes and for satisfying the varying skill level of the individual user. The static maps were deemed to be easy to use and versatile, while the animated maps could be made more useful if animation controls were provided. The split-screen concept of the interactive maps was highlighted as particularly effective for map comparison. Overall, interactive maps were identified as the preferred map type for comparing patterns of injury and related socio-demographic risk factors. Information collected from the user-tests is being used to expand and refine the injury web maps for Toronto, and could inform other public health-related geo-visualization projects.

Late-onset bleb infections: prevalence and risk factors.

OBJECTIVE: The purpose of this study was to determine the rate and course of blebitis/late endophthalmitis 5-10 years post-filtration surgery and to evaluate risk factors. DESIGN: Retrospective chart review. PARTICIPANTS: Three hundred fifty consecutive patients undergoing filtration surgery from January 1, 1996, to December 31, 2001, by a single surgeon. Five hundred twenty-one surgeries were evaluated. METHODS: Data recorded included patient demographics, systemic disease(s), glaucoma type, left or right eye, date of surgery, last follow-up date, surgical procedure details, postoperative antimetabolite injections, bleb manipulations, bleb leaks and treatment, date of infection, type of infection, pre- and postinfection visual acuity, intraocular pressure (preinfection, during, and postinfection), treatment, and functionality of the bleb after infection. Statistical analysis used for assessment of risk factors included Fisher's exact test and the Student's t test analysis. RESULTS: There were a total of 5 bleb-related infections (0.96%), 4 blebitis and 1 endophthalmitis, occurring at a mean of 31.3 months after surgery. Three occurred in blacks and 2 in Caucasians. The mean age at surgery for the infected group was 53.5 years compared with 64.7 years for those with no infection. Mitomycin C was used in 4 of the 5 cases compared with in 52% of controls. Four underwent suture lysis. Bleb leaks occurred in 4 cases. The bleb remained functional and vision unchanged in the 4 blebitis cases; however, the endophthalmitis case lost vision and had uncontrolled pressure following the infection. CONCLUSIONS: We report a 0.96% bleb infection rate with a 5.3-year mean follow-up. Bleb leak, black race, and bleb manipulation were risk factors for infection.

Correlation between the indiana bleb appearance grading scale and intraocular pressure after phacotrabeculectomy.

PURPOSE: To investigate the relationship between bleb morphology, recorded using the Indiana Bleb Appearance Grading Scale (IBAGS), and intraocular pressure (IOP) after phacotrabeculectomy. METHODS: Two years postphacotrabeculectomy, a single observer compared bleb morphology to the IBAGS standard photographs in 76 eyes of 76 patients. In addition, the presence or absence of microcysts was recorded. IOP was also measured. RESULTS: On multivariate analysis increasing bleb height was associated with a low IOP (P=0.017). An increase in IBAGS height score by 1 U resulted in a reduction in IOP of 2.16 mm Hg (95% confidence interval=0.40-3.92 mm Hg). In this study, there was no association between vascularity, bleb extent or microcysts, and IOP. There were no cases of bleb leak in this series. CONCLUSIONS: Two years postphacotrabeculectomy increased bleb height, as measured by the IBAGS, was associated with a decrease in IOP, with a 1 point increase in IBAGS height score resulting in a decrease of 2.16 mm Hg. We found no association between bleb extent, vascularity, or the presence or absence of conjunctival microcysts. As there were no cases of bleb leak in this study this characteristic could not be evaluated.

Intermediate-term outcome and success of superior versus inferior Ahmed Glaucoma Valve implantation.

PURPOSE: The superotemporal quadrant is usually the implantation site of choice for glaucoma drainage devices. Inferior placement of glaucoma drainage device is considered technically difficult. The purpose was to determine the success rates, complications, and visual outcome of superior versus inferior Ahmed Glaucoma Valve implantation. PATIENTS AND METHODS: A retrospective review of the records of 83 eyes (77 patients) that underwent Ahmed Glaucoma Valve surgery from 1997 to 2004. Thirty-one eyes had superior insertion (SI) versus 52 eyes with inferior insertion (II). Demographic, preoperative, and postoperative data including intraocular pressure (IOP), visual acuity, and number of medications, and complications were recorded. Success was defined as postoperative IOP between 5 and 21 mm Hg and at least a 20% reduction from baseline IOP. RESULTS: The mean postoperative IOPs at 6 months, 1, 2, 2.5, and 3 years were 13.5+/-3.2 mm Hg versus 12.8+/-3.6 mm Hg (P=0.76), 12.5+/-3.1 mm Hg versus 13.0+/-4.0 mm Hg (P=0.5), 15.7+/-6.2 mm Hg versus 12.6+/-4.7 mm Hg (P=0.06), 13.2+/-3.0 mm Hg versus 12.6+/-3.3 mm Hg (P=0.70), and 14.5+/-3.0 mm Hg versus 13.7+/-5.0 mm Hg (P=0.73) in the SI group versus the II group, respectively. The success rates were similar between the groups over the study period with 87.0% versus 86.5%, 71.5% versus 73.0%, and 71.5% versus 64.6% for SI versus II at 12, 24, and 36 months, respectively. There were more complications in the II group; however, only wound dehiscence and transient diplopia were statistically significant (P=0.04 and 0.001, respectively). The number of glaucoma medications was lower in the SI during the first 3 months but nonsignificant thereafter. CONCLUSIONS: There was no significant difference in IOP control between SI and II over 36 months. II should be considered when there are limitations to SI.

Ahmed glaucoma valve implantation in uveitic glaucoma versus open-angle glaucoma patients.

BACKGROUND: The poor long-term success rate of repeat trabeculectomies in refractory uveitic glaucoma (UG) patients has led to the use of glaucoma drainage devices (GDDs). However, the success and complication rates of GDDs in UG patients utilizing a control group with standard demographic data, design, and surgical technique have never been evaluated. METHODS: Fifteen patients (15 eyes) with chronic uveitis and 53 patients (53 eyes) with uncontrolled open-angle glaucoma (OAG) who underwent Ahmed glaucoma valve (AGV) implantation were included in a retrospective, comparative, case-controlled study. Postoperative intraocular pressure (IOP), number of antiglaucoma medications, visual acuity, and complications were compared. RESULTS: There was a significant difference between the UG versus the OAG group with respect to age only (59.3 years vs 68.4 years, p = 0.006). Regression analysis of the postoperative IOP controlled for age and glaucoma type, and preoperative IOP revealed significantly lower IOP in the UG group at 1 month (p = 0.04; 95% confidence interval [CI] -5.9 to 0.15) and 2 months (p = 0.008; 95% CI -6.0 to 0.97). No significant differences were found at 3, 6, 12, 24, and 30 months. The cumulative success rates at 3 to 30 months for the UG and OAG groups were 80% to 66.6% versus 84.9% to 57% (p = 0.713), respectively. The only complication between the 2 groups that was significantly different was tube removal, which occurred more often in the UG group (p = 0.018). INTERPRETATION: AGV implantation is an effective and safe procedure in the management of UG, similar to primary OAG.

Predictors of postacute mortality following traumatic brain injury in a seriously injured population.

BACKGROUND: Traumatic brain injury (TBI) is a primary cause of injury mortality in developed countries but less is known about the impact of TBI on postacute mortality in large study populations. This study investigates the rate and predictors of postacute mortality (1-9 years after the initial injury) of severely injured persons with TBI in the Province of Ontario from April 1, 1993 to March 31, 1995. METHOD: Cases were identified (n = 2,721) from the Ontario Trauma Registry Comprehensive Data Set based on lead trauma hospitals in the province which also provided data on predictors. Severely injured patients (n = 557) who had lower extremity injuries during the sample time period formed a control population. RESULTS: Poisson regression modeling showed that having a TBI was a significant predictor of premature death controlling for age and injury severity. Age, the number of comorbidities, injury severity, mechanism of injury, and discharge destination were significant predictors in the multivariate analyses for the TBI population. CONCLUSIONS: This research quantifies the elevated risk of premature death in the postacute period for seriously injured adults with TBI and identifies factors most associated with highest mortality rates in this population.

Medical students' attitudes on diversity when applying to Toronto's ophthalmology residency program.

BACKGROUND: Affirmative action is a controversial admissions policy practised by universities in the United States and other countries around the world. It is currently not used at the University of Toronto ophthalmology residency program. A survey was conducted to determine the opinions of applicants as to the role that affirmative action and quotas should play during the admissions process and to determine the current ethnic breakdown of the applicants to ophthalmology. METHODS: A survey of 14 questions was sent out to all 72 medical students applying for a residency position in our program. The response rate was 58%. The students were asked to agree or disagree on a 5-point Likert scale with statements related to ethnicity, gender, and whether affirmative action policies exist or should exist for certain groups. RESULTS: The majority of the respondents (26/42, 62%) considered themselves an ethnic minority, and 57% (24/42) considered themselves a visible minority. Most (32/42) felt that the sex of the applicant should not play a role in the selection process. Only 24% (10/42) supported affirmative action, and only 12% (5/42) supported quotas for minority applicants. INTERPRETATION: The majority of survey respondents in this study did not support affirmative action or quotas at the University of Toronto ophthalmology program. The applicants to this program represent a diverse group of individuals from a multitude of ethnic, cultural, and racial backgrounds, and, in their average opinion, affirmative action policies would not benefit our admissions program.