Self-harm in adolescence and risk of crash: a 13-year cohort study of novice drivers in New South Wales, Australia

INTRODUCTION

Self-harm and suicide are leading causes of morbidity and death for young people, worldwide. Previous research has identified self-harm is a risk factor for vehicle crashes, however, there is a lack of long-term crash data post licensing that investigates this relationship. We aimed to determine whether adolescent self-harm persists as crash risk factor in adulthood.

METHODS

We followed 20 806 newly licensed adolescent and young adult drivers in the DRIVE prospective cohort for 13 years to examine whether self-harm was a risk factor for vehicle crashes. The association between self-harm and crash was analysed using cumulative incidence curves investigating time to first crash and quantified using negative binominal regression models adjusted for driver demographics and conventional crash risk factors.

RESULTS

Adolescents who reported self-harm at baseline were at increased risk of crashes 13 years later than those reporting no self-harm (relative risk (RR) 1.29: 95% CI 1.14 to 1.47). This risk remained after controlling for driver experience, demographic characteristics and known risk factors for crashes, including alcohol use and risk taking behaviour (RR 1.23: 95% CI 1.08 to 1.39). Sensation seeking had an additive effect on the association between self-harm and single-vehicle crashes (relative excess risk due to interaction 0.87: 95% CI 0.07 to 1.67), but not for other types of crashes.

DISCUSSION

Our findings add to the growing body of evidence that self-harm during adolescence predicts a range of poorer health outcomes, including motor vehicle crash risks that warrant further investigation and consideration in road safety interventions. Complex interventions addressing self-harm in adolescence, as well as road safety and substance use, are critical for preventing health harming behaviours across the life course.

Acculturation and risk of traffic crashes in young Asian-born Australian drivers

The study examines changes over time in crash risk differences between young Australian drivers born in Asia and those born in Australia.Data from the 2003 baseline survey of the DRIVE cohort of 20 806 young drivers aged 17-24 years were linked to police, hospital and death data up until 2016. The association between country of birth and crash was investigated using flexible parametric survival models adjusted for confounders.Six months after baseline, the crash risk in Asian-born drivers was less than half that of their Australian-born counterparts (mean HR, MHR 0.41; 95% CI 0.29 to 0.57), only to increase steadily over time to resemble that of Australian-born drivers 13 years later (MHR 0.94; 95% CI 0.66 to 1.36).This is likely to be associated with acculturation and the adoption by young Asian-born Australian drivers of driving behaviour patterns akin to those born locally. This needs to be considered in future road safety campaigns.

Crash characteristics of on-road single-bicycle crashes: an under-recognised problem

Compared with crashes with motor vehicles, single-bicycle crashes are an under-recognised contributor to cycling injury and the aetiology is poorly understood. Using an in-depth crash investigation technique, this study describes the crash characteristics and patient outcomes of a sample of cyclists admitted to hospital following on-road bicycle crashes. Enrolled cyclists completed a structured interview, and injury details and patient outcomes were extracted from trauma registries. Single-bicycle crashes (n=62) accounted for 48% of on-road crashes and commonly involved experienced cyclists. Common single-bicycle crash types included loss-of-control events, interactions with tram tracks, striking potholes or objects or resulting from mechanical issues with the bicycle. To address single-bicycle crashes, targeted countermeasures are required for each of these specific crash types.

Evidence for the 'safety in density' effect for cyclists: validation of agent-based modelling results

The safety in numbers (SiN) effect for cyclists is widely observed but remains poorly understood. Although most studies investigating the SiN phenomenon have focused on behavioural adaptation to 'numbers' of cyclists in the road network, previous work in simulated environments has suggested SiN may instead be driven by increases in local cyclist spatial density, which prevents drivers from attempting to move through groups of oncoming cyclists. This study therefore set out to validate the results of prior simulation studies in a real-world environment. Time-gap analysis of cyclists passing through an intersection was conducted using 5 hours of video observation of a single intersection in the city of Melbourne, Australia, where motorists were required to 'yield' to oncoming cyclists. Results demonstrated that potential collisions between motor vehicles and cyclists reduced with increasing cyclists per minute passing through the intersection. These results successfully validate those observed under simulated conditions, supporting evidence of a proposed causal mechanism related to safety in density rather than SiN, per se. Implications of these results for transportation planners, cyclists and transportation safety researchers are discussed, suggesting that increased cyclist safety could be achieved through directing cyclists towards focused, strategic corridors rather than dispersed across a network.

Cyclist exposure to the risk of car door collisions in mixed function activity centers: A study in Melbourne, Australia

OBJECTIVE

The objective of this study is to describe key risks related to dooring collisions on roads in mixed function activity centers by examining video footage recorded onboard the bicycles of cyclists riding through this road environment. The study aims to enhance our understanding of the risk associated with cyclist door collisions on these roads and to provide a focus for future studies that aim to identify measures that enhance cyclist safety.

METHOD

The study measured 4 key risk exposures (per hour and kilometer), namely, on-street parked cars and 3 conditions associated with parked cars being accessed or egressed: door opened (a) after the cyclist passes (give-way event); (b) in the path of the cyclist without collision (obstruction event); and (c) in the path of the cyclist with collision (collision event). Exposure to the risk factors was measured using video footage recorded onboard the bicycles of adult cyclists (n = 25) as they rode through this road environment. The average speed of cyclists was also estimated from these video data and related to the measures of exposure.

RESULTS

The cycling experiences of the participants were observed over 3 h 58 min and 84.0 km. On average, the sample was exposed to 1,166 parked car events per hour (55 per kilometer), 6.9 give-way events per hour (0.3 per kilometer), 2.3 obstruction events per hour (0.1 per kilometer), and no collision events. There were 9 instances of obstruction events. In most cases, the cyclist was clearly visible (n = 7; 77.8%) and modified his or her position to avoid the door (n = 8; 88.9%). Moreover, the door was opened by the driver in nearly all cases (n = 8; 88.9%), primarily to exit the vehicle (n = 4; 44.4%) or enter the vehicle (n = 3; 33.3%). The average speed of cyclists was 22.7 km/h (SD = 4.1 km/h), and average speed tended to reduce as exposure to parked car events increased.

CONCLUSION

Cyclists seldom interact with a vehicle occupant accessing or egressing a parked car, yet a concerning proportion of these interactions involve the occupant opening the door in the path of the cyclist, rather than waiting for the cyclist to pass. This suggests that there is still considerable need to identify measures that increase the likelihood that a vehicle occupant will look for cyclists before opening the car door, particularly in road environments where longer-term solutions such as physical separation are not readily achieved.

Distracting and risky behaviours while cycling: a comparison of group and non-group riders in Western Australia

BACKGROUND

Use of mobile phones and portable audio equipment and alcohol are known to negatively affect cycling ability. Evidence suggests that cyclists may be less likely to engage in these behaviours while riding in a group; however, it is unknown whether group riders are also at reduced risk when participating in non-group riding.

OBJECTIVE

To examine the association between group riding participation and the use of mobile phones and portable audio equipment and alcohol while non-group riding in Perth, Western Australia.

METHODS

A cross-sectional analysis of an online questionnaire was undertaken. Group and exclusive non-group riders were compared and separate binary logistic regression models were used to examine the association between group riding participation and the use of mobile phones and portable audio equipment and alcohol while non-group riding, controlling for gender, age, education and frequency of non-group riding.

RESULTS

Participants included 365 cyclists: 187 exclusive non-group riders (51.2%) and 178 group riders (48.8%). Group riders were less likely to have possibly cycled while over the legal blood alcohol limit in the past 12 months (OR: 0.56, 95% CI 0.34 to 0.92) and were less likely to ever use portable audio equipment (OR: 0.57, 95% CI 0.34 to 0.94) than exclusive non-group riders, while participating in non-group riding. Group riding status was not associated with mobile phone use.

CONCLUSIONS

This study provides early evidence that there may be differences between group and non-group riders that impact on their safety behaviours while participating in non-group riding.

Determinants of the occupational environment and heavy vehicle crashes in Western Australia: A case-control study

OBJECTIVE

To determine the association between a heavy vehicle driver's work environment, including fatigue-related characteristics, and the risk of a crash in Western Australia.

METHODS

This case-control study included 100 long-haul heavy vehicle drivers who were involved in a police-reported crash in WA and 100 long-haul heavy vehicle drivers recruited from WA truck stops, who were not involved in a crash in the previous 12 months. Driver demographics and driving details, work environment, vehicle and sleep-related characteristics were obtained using an interviewer-administered questionnaire. Drivers were tested for obstructive sleep apnoea using an overnight diagnostic device. Conditional multiple logistic regression analysis was undertaken to determine work environment-related factors associated with crash involvement.

RESULTS

After accounting for potential confounders, driving a heavy vehicle with an empty load was associated with almost a three-fold increased crash risk compared to carrying general freight (adjusted OR: 2.93, 95% CI: 1.17-7.34). Driving a rigid heavy vehicle was associated with a four-fold increased risk of crashing compared to articulated heavy vehicles (adjusted OR: 4.08, 95% CI: 1.13-14.68). The risk of crashing was almost five times higher when driving more than 50% of the trip between midnight and 5.59am (adjusted OR: 4.86, 95% CI: 1.47-16.07). Furthermore, the risk of crashing significantly increased if the time since the last break on the index trip was greater than 2h (adjusted OR: 2.18, 95% CI: 1.14-4.17). Drivers with more than 10 years driving experience were 52% less likely to be involved in a crash (adjusted OR: 0.48, 95% CI: 0.23-0.99).

CONCLUSION

The results provide support for an association between a driver's work environment, fatigue-related factors, and the risk of heavy vehicle crash involvement. Greater attention needs to be paid to the creation of a safer work environment for long distance heavy vehicle drivers.

Obstructive sleep apnea, health-related factors, and long distance heavy vehicle crashes in Western Australia: a case control study

STUDY OBJECTIVES

To determine the association between obstructive sleep apnea (OSA), health-related factors and the likelihood of heavy vehicle crashes in Western Australia (WA).

METHODS

This case-control study included 100 long-haul heavy vehicle drivers who were involved in a police-reported crash in WA during the study period (cases) and 100 long-haul heavy vehicle drivers recruited from WA truck stops, who were not involved in a crash during the past year (controls). Driver demographics, health, and fatigue-related characteristics were obtained using an interviewer administered questionnaire. Drivers were tested for OSA using a diagnostic Flow Wizard. Logistic regression was used to determine health-related factors associated with crash involvement among long distance heavy vehicle drivers.

RESULTS

Heavy vehicle drivers diagnosed with OSA through the use of the FlowWizard were over three times more likely to be involved in a crash than drivers without OSA (adjusted OR: 3.42, 95% CI: 1.34-8.72). The risk of crash was significantly increased if heavy vehicle drivers reported a diagnosis of depression (adjusted OR: 6.59, 95% CI: 1.30-33.24) or had not completed fatigue management training (adjusted OR: 6.05, 95% CI: 1.80-20.24). Crash risk was 74% lower among older drivers (> 35 years) than younger drivers (adjusted OR: 0.25, 95% CI: 0.08-0.82).

CONCLUSION

The results suggest that more rigorous screening and subsequent treatment of OSA and depression by clinicians as well as compulsory fatigue management training may reduce crashes among heavy vehicle drivers.

COMMENTARY

A commentary on this article appears in this issue on page 409.

Geospatial analysis of cyclist injury trends: an investigation in Melbourne, Australia

OBJECTIVE

This study applied geospatial analysis to explore spatial trends in cycling-related injury in Melbourne, Australia, in order to identify an area where injury density was reducing against expectation. The crash characteristics and cycling environment of the identified area were examined to better understand factors related to cycling safety.

METHOD

Two methods were used to examine spatial trends in cycling-related injury. Firstly, cycling injury density was calculated using a kernel density estimation method for the years 2000 to 2011. This was used to examine patterns in injury density across Melbourne over an extended time period. Secondly, absolute change in injury density was calculated between 2005 and 2011. From this, a geographical area presenting a reduced injury density was selected for a case study, and crash characteristics of the area were obtained for the observational period. This led to discussion on which changes to the cycling environment, if any, may be associated with the reduced injury rate.

RESULTS

Injury density in Melbourne had been progressively increasing between 2000 and 2011, with a nearly 3-fold increase in the peak injury density over that period. Decreases were observed in some locations between 2005 and 2011, and a geographical area to the southeast of Melbourne experienced a more significant decrease than others. This appeared to be associated with a combination of behavior and road infrastructure change, although a lack of data to verify change in cycling exposure prevented more definitive associations from being established.

CONCLUSION

The apparent positive response of the injury rate to behavior and road infrastructure interventions is promising, yet the injury rate is unlikely to achieve the government's road safety target of 30% reduction in serious injuries by 2022. Moreover, the number of injuries sustained at the most common crash location appears to be increasing. Further research is necessary to discern which specific features of the urban road infrastructure have an effect on the risk of injury to a cyclist and which combination of features is consistent with a safe cycling environment.

Anoxia-induced changes in optimal substrate for peripheral nerve

Hyperglycemia accentuates the injury produced by anoxia both in the central and peripheral nervous system. To understand whether this is a consequence of changes in metabolic pathways produced by anoxia, the effect of the metabolic substrate used by the rat peripheral nerve on the nerve action potential (NAP) was studied in the presence and absence of anoxia. In the continuously oxygenated state, the NAP was well preserved with glucose, lactate, as well as with high concentrations of sorbitol and fructose but not β-hydroxybutyrate, acetate or galactose. With intermittent anoxia, the pattern of substrate effects on the NAP changed markedly so that low concentrations of fructose became able to support neurophysiologic activity but not high concentrations of glucose. These alterations occurred gradually with repeated episodes of anoxia as reflected by the progressive increase in the time needed for the NAP to disappear during anoxia when using glucose as substrate. This "preconditioning" effect was not seen with other substrates and an opposite effect was seen with lactate. In fact, the rate at which the NAP disappeared during anoxia was not simply related to degree of recovery after anoxia. These are distinct phenomena. For example, the NAP persisted longest during anoxia in the setting of hyperglycemia but this was the state in which the anoxic damage was most severe. Correlating the results with existing literature on the metabolic functions of Schwann cells and axons generates testable hypotheses for the mechanism of hyperglycemic damage during anoxia and lead to discussions of the role for a metabolic shuttle between Schwann cells and axons as well as a potential important role of glycogen.

The role of sleepiness, sleep disorders, and the work environment on heavy-vehicle crashes in 2 Australian states

Heavy-vehicle driving involves a challenging work environment and a high crash rate. We investigated the associations of sleepiness, sleep disorders, and work environment (including truck characteristics) with the risk of crashing between 2008 and 2011 in the Australian states of New South Wales and Western Australia. We conducted a case-control study of 530 heavy-vehicle drivers who had recently crashed and 517 heavy-vehicle drivers who had not. Drivers' crash histories, truck details, driving schedules, payment rates, sleep patterns, and measures of health were collected. Subjects wore a nasal flow monitor for 1 night to assess for obstructive sleep apnea. Driving schedules that included the period between midnight and 5:59 am were associated with increased likelihood of crashing (odds ratio = 3.42, 95% confidence interval: 2.04, 5.74), as were having an empty load (odds ratio = 2.61, 95% confidence interval: 1.72, 3.97) and being a less experienced driver (odds ratio = 3.25, 95% confidence interval: 2.37, 4.46). Not taking regular breaks and the lack of vehicle safety devices were also associated with increased crash risk. Despite the high prevalence of obstructive sleep apnea, it was not associated with the risk of a heavy-vehicle nonfatal, nonsevere crash. Scheduling of driving to avoid midnight-to-dawn driving and the use of more frequent rest breaks are likely to reduce the risk of heavy-vehicle nonfatal, nonsevere crashes by 2-3 times.

Work-related road traffic injury: a multilevel systems protocol

Background

Although road traffic injury is reported as the leading cause of work-related death in Australia, it is not clear, due to limitations in previous methods used, just how large a burden it is. Many organisations are unaware of the extent of work-related road traffic injury and, importantly, what can be done to reduce the burden. The proposed research will (i) estimate the prevalence of work-related road traffic injury and (ii) identify the organisational determinants associated with work-related road traffic injury.

Methods and design

The current study is designed to enumerate the problem and identify the individual driver-level, the supervisor-level and organisational-level factors associated with work-related road traffic injury. The multilevel systems protocol will involve a series of cross-sectional surveys administered to drivers of fleet vehicles (n=1200), supervisors of the drivers (n=1200) and senior managers (n=300) within the same organisation.

Discussion

The novel use of the multilevel systems protocol is critical to be able to accurately assess the specific determinants of driving safety within each context of an organisation.

Results

The results are expected to highlight that reducing injury in the workplace requires more than just individual compliance with safety procedures. It will also establish, for the first time, an occupational translation taskforce to ensure that the research findings are adopted into work-place practice and thereby directly contribute to reductions in work-related road traffic injury.

Evaluation of the Vietnamese A6 mortality reporting system: injury as a cause of death

BACKGROUND

Despite the fact that the A6 mortality reporting system has been operating for almost 20 years in Vietnam, there has been no systematic evaluation of the system. This study assesses the completeness, sensitivity and positive predictive value of the system in relation to injury related mortality.

METHODS

Evaluation of the A6 system was undertaken in three (geographically distributed) provinces in Vietnam. Deaths identified in the A6 system were compared with deaths identified by an independent consensus panel to determine the per cent completeness of the A6 system. Verbal autopsies (VA) were conducted for all identified deaths from the consensus panels, and the sensitivity and positive predictive value of the A6 system were assessed using the VAs as the reference.

RESULTS

5273 deaths were identified from the A6 system with a further 340 cases identified by the independent consensus panel (total n=5613). Injury related deaths accounted for 13.6% (n=763) of all deaths with an overall injury mortality rate of 55.3 per 100 000 person years. The per cent completeness of the A6 system in relation to injury deaths was 93.9% with a sensitivity of 75.4%, specificity of 98.4% and positive predictive value of 88.4%.

CONCLUSIONS

The A6 mortality reporting system is embedded within the commune health system and is the lead mortality reporting system for the Ministry of Health. The system performs well in relation to its completeness and classification of injury related deaths. With further enhancements and ongoing support from government and donor agencies, the A6 system will be a valuable resource for identifying and planning preventive strategies targeting the leading causes of injury related deaths in Vietnam.

The effect of topical phenytoin on healing in diabetic foot ulcers: a randomized controlled trial

AIM

The aim of the study was to evaluate the effect of topical phenytoin on healing in diabetic foot ulcers. A randomized, controlled, double-blind, clinical trial was conducted.

METHODS

A phenytoin dressing and a control dressing were manufactured. Individuals who were ≥ 18 years of age with peripheral neuropathy, an ankle brachial pressure index > 0.5 and a diabetic foot ulcer ≥ 4 weeks' duration were independently randomized to the phenytoin group (31 participants) or the control group (34 participants). Participants with renal disease, ankle brachial pressure index < 0.5, necrosis or osteomyelitis were excluded. Subjects received standard wound care and dressing application. Primary endpoint analysis (diabetic foot ulcer closed or not at 16 weeks) was calculated by survival analysis.

RESULTS

Participants (n = 65, 52 with Type 2 diabetes) were treated for a maximum of 16 weeks. Sixty per cent of the diabetic foot ulcers closed overall (18 in the phenytoin group, 20 in the control group) with no statistically significant differences in complete healing or in diabetic foot ulcer area over time between the two groups. At 24-weeks follow-up, one diabetic foot ulcer had recurred.

CONCLUSIONS

There were no differences in diabetic foot ulcer closure rates or in diabetic foot ulcer area over time between the two groups. This study does not support the use of phenytoin in the treatment of diabetic foot ulcers.

Motorcycle rider training for the prevention of road traffic crashes

BACKGROUND

Riding a motorcycle (a two-wheeled vehicle that is powered by a motor and has no pedals) is associated with a high risk of fatal crashes, particularly in new riders. Motorcycle rider training has therefore been suggested as an important means of reducing the number of crashes, and the severity of injuries.

OBJECTIVES

To quantify the effectiveness of pre- and post-licence motorcycle rider training on the reduction of traffic offences, traffic crash involvement, injuries and deaths of motorcycle riders.

SEARCH STRATEGY

We searched the Cochrane Injuries Group Specialised Register, CENTRAL (The Cochrane Library 2008, Issue 3), TRANSPORT, MEDLINE, EMBASE, CINAHL, WHOLIS (World Health Organization Library Information System), PsycInfo, LILACS (Latin American and Caribbean Health Sciences), ISI Web of Science: Social Sciences Citation Index (SSCI), ERIC, ZETOC and SIGLE. Database searches covered all available dates up to October 2008. We also checked reference lists of relevant papers and contacted study authors in an effort to identify published, unpublished and ongoing trials related to motorcycle rider training.

SELECTION CRITERIA

We included all relevant intervention studies such as randomised and non-randomised controlled trials, interrupted time-series and observational studies such as cohort and case-control studies.

DATA COLLECTION AND ANALYSIS

Two review authors independently analysed data about the study population, study design and methods, interventions and outcome measures as well as data quality from each included study, and compared the findings. We resolved differences by discussion with a third review author.

MAIN RESULTS

We reviewed 23 studies: three randomised trials, two non-randomised trials, 14 cohort studies and four case-control studies. Five examined mandatory pre-licence training, 14 assessed non-mandatory training, three of the case-control studies assessed 'any' type of rider training, and one case-control study assessed mandatory pre-licence training and non-mandatory training. The types of assessed rider training varied in duration and content.Most studies suffered from serious methodological weaknesses. Most studies were non-randomised and controlled poorly for confounders. Most studies also suffered from detection bias due to the poor use of outcome measurement tools such as the sole reliance upon police records or self-reported data. Small sample sizes and short follow-up time after training were also common.

AUTHORS' CONCLUSIONS

Due to the poor quality of studies identified, we were unable to draw any conclusions about the effectiveness of rider training on crash, injury, or offence rates. The findings suggest that mandatory pre-licence training may be an impediment to completing a motorcycle licensing process, possibly indirectly reducing crashes through a reduction in exposure. It is not clear if training (or what type) reduces the risk of crashes, injuries or offences in motorcyclists, and a best rider training practice can therefore not be recommended. As some type of rider training is likely to be necessary to teach motorcyclists to ride a motorcycle safely, rigorous research is needed.

Incidence, risk, and protective factors of mild traumatic brain injury in a cohort of Australian nonprofessional male rugby players

BACKGROUND

Mild traumatic brain injury (mTBI) is an emerging public health issue in high-contact sports. Understanding the incidence along with the risk and protective factors of mTBI in high-contact sports such as rugby is paramount if appropriate preventive strategies are to be developed.

PURPOSE

To estimate the incidence and identify the risk and protective factors of mTBI in Australian nonprofessional rugby players.

STUDY DESIGN

Cohort study; Level of evidence, 2.

METHODS

A cohort of 3207 male nonprofessional rugby players from Sydney, Australia, was recruited and followed over 1 or more playing seasons. Demographic information, history of recent concussion, and information on risk and protective factors were collected. The incidence of mTBI was estimated and the putative risk and protective factors were modeled in relation to mTBI.

RESULTS

The incidence of mTBI was 7.97 per 1000 player game hours, with 313 players (9.8%) sustaining 1 or more mTBIs during the study. Players who reported always wearing protective headgear during games were at a reduced risk (incident rate ratio [IRR], 0.57; 95% confidence interval [CI], 0.40-0.82) of sustaining an mTBI. In contrast, the likelihood of mTBI was almost 2 times higher among players who reported having sustained either 1 (IRR, 1.75; 95% CI, 1.11-2.76) or more mTBIs (IRR, 1.65; 95% CI, 1.11-2.45) within the 12 months before recruitment.

CONCLUSION

Nonprofessional rugby has a high incidence of mTBI, with the absence of headgear and a recent history of mTBI associated with an increased risk of subsequent mTBI. These findings highlight that both use of headgear and the management of prior concussion would likely be beneficial in reducing the likelihood of mTBI among nonprofessional rugby players, who compose more than 99% of rugby union players in Australia.

The burden of fatal and non-fatal injury in rural India

BACKGROUND

Little is known about the burden or causes of injury in rural villages in India.

OBJECTIVE

To examine injury-related mortality and morbidity in villages in the state of Andhra Pradesh, India.

METHODS

A verbal-autopsy-based mortality surveillance study was used to collect mortality data on all ages from residents in 45 villages in 2003-2004. In early 2005, a morbidity survey in adults was carried out using stratified random sampling in 20 villages. Participants were asked about injuries sustained in the preceding 12 months. Both fatal and non-fatal injuries were coded using classification methods derived from ICD-10.

RESULTS

Response rates for the mortality surveillance and morbidity survey were 98% and 81%, respectively. Injury was the second leading cause of death for all ages, responsible for 13% (95% CI 11% to 15%) of all deaths. The leading causes of fatal injury were self-harm (36%), falls (20%), and road traffic crashes (13%). Non-fatal injury was reported by 6.7% of survey participants, with the leading causes of injury being falls (38%), road traffic crashes (25%), and mechanical forces (16.1%). Falls were more common in women, with most (72.3%) attributable to slipping and tripping. Road traffic injuries were sustained mainly by men and were primarily the result of motorcycle crashes (48.8%).

DISCUSSION

Injury is an important contributor to disease burden in rural India. The leading causes of injury-falls, road traffic crashes, and suicides-are all preventable. It is important that effective interventions are developed and implemented to minimize the impact of injury in this region.

Barriers to, and factors associated, with observed motorcycle helmet use in Vietnam

This study investigated barriers to, and factors associated with, observed motorcycle helmet use among motorcyclists in Hai Duong Province, Vietnam. The findings highlighted an array of factors associated with observed helmet use namely, support for universal helmet legislation and a positive attitude towards what might be perceived as negative attributes of helmet use such as inconvenience and discomfort in hot weather. As well, older age (greater than 25 years in age), riding on a compulsory road, being a driver, trips of greater than 10 km, higher levels of education (having a university degree and higher) were found to be key determinants of helmet use. Despite over 95% of motorcyclists disagreeing with the statement that wearing a helmet does not reduce the severity of head injury in a crash, most motorcyclists believed that helmets did not need to be worn for a short trip. Overall, only 23% of motorcyclists were observed wearing a helmet. The authors conclude that efforts to increase helmet use need to focus on the necessity for universal helmet legislation in association with identifying solutions to reduce the negative attitudes towards helmet use.

Motorcycle helmets in Vietnam: ownership, quality, purchase price, and affordability

OBJECTIVES

This study investigated motorcycle helmet ownership, quality, purchase price, and affordability in Vietnam.

METHOD

A random sample of motorcyclists was interviewed to investigate aspects of helmet ownership, the purchase price, and affordability of a motorcycle helmet. Multivariate modeling conducted to determine factors associated with the purchase price and affordability of motorcycle helmets. Helmet quality was assessed based on current legal requirements in Vietnam.

RESULTS

The prevalence of helmet use in Vietnam remains low (23.3%) despite a high level of helmet ownership (94%), indicating that this is an important area for public health intervention. Overall the quality of helmets appeared to be good; however, few helmets displayed legally required information. Motorcyclists with a high income purchase more helmets for their household rather than more expensive helmets.

CONCLUSION

To ensure that helmets are accessible to the community, policy-makers need to consider pricing motorcycle helmets at a price indicated by the results of this study. Prior to universal motorcycle helmet legislation, the government will also need to ensure that standard helmets are available and that enforcement is at a level to ensure that motorcycle helmets are actually used.

A cohort study of 20,822 young drivers: the DRIVE study methods and population

BACKGROUND AND OBJECTIVE

Research on young drivers directly linking risk factors to serious injury and death outcomes is required. The DRIVE Study was established to facilitate this aim. This paper outlines the study methods and describes the population that has been recruited, in order to demonstrate that the necessary heterogeneity in risk factors has been attained.

DESIGN, SETTING AND PARTICIPANTS

Drivers aged 17-24 years holding their first-stage provisional driver's licence from New South Wales, Australia, were recruited into a prospective cohort study. The participants were contacted by mail and asked to complete the study questionnaire at an online site or via a mailed questionnaire. Baseline data collection involved a questionnaire with questions to drivers about their training, risk perception, driver behavior, sensation-seeking behavior and mental health. Participants gave consent for prospective data linkage to their data on licensing, crashes and injuries, held in routinely collected databases.

RESULTS

20 822 drivers completed the baseline questionnaire, of whom 45.4% were men, 74.3% resided in capital cities and 25.7% in regional or remote areas. The recruited study population showed a wide variation in the risk factors under examination. For example, almost 40% of drivers reported drinking alcohol at hazardous levels and about 32% of participants seemed to be at a high or very high risk of psychological distress. Participants reported a mean of 67.3 h (median 60 h) of supervised driver training while holding their learner's permit.

CONCLUSIONS

The DRIVE Study has a robust study design aimed at minimizing bias in the collection of outcome data. Analyses of baseline data showed substantial heterogeneity of risk factors in the study population. Subsequent prospective linkages comparing relative differences in exposures at baseline with the outcomes of interest have the potential to provide important new information needed to develop targeted interventions aimed at young drivers.

The contribution of passengers versus mobile phone use to motor vehicle crashes resulting in hospital attendance by the driver

There is evidence that mobile phone use while driving (including hands-free) is associated with motor vehicle crashes. However, whether the effects of mobile phone use differ from that of passengers in the vehicle remains unclear. The aim of this research was to estimate the risk of crash associated with passenger carriage and compare that with mobile phone use. A case-control study ('passenger study') was performed in Perth, Western Australia in 2003 and 2004. Cases were 274 drivers who attended hospital following a motor vehicle crash and controls were 1096 drivers (1:4 matching) recruited at service stations matched to the location and time and day of week of the crash. The results were compared with those of a case-crossover study ('mobile phone study') undertaken concurrently (n=456); 152 cases were common to both studies. Passenger carriage increased the likelihood of a crash (adjusted odds ratio (adj. OR), 95% confidence interval (95% CI), 1.6, 1.1-2.2). Drivers carrying two or more passengers were twice as likely to crash as unaccompanied drivers (adj. OR 2.2, 95% CI 1.3-3.8). By comparison, driver's use of a mobile phone within 5 min before a crash was associated with a fourfold increased likelihood of crashing (OR 4.1, 95% CI 2.2-7.7). Passenger carriage and increasing numbers of passengers are associated with an increased likelihood of crash, though not to the same extent as mobile phone use. Further research is needed to investigate the factors underlying the increased risks.

Design of a bio-mathematical prediction model using serum tumor markers and immunohistochemistry in peritoneal carcinomatosis with ovarian involvement: a pilot study

The diagnosis of disseminated intra-abdominal malignancy in women with ovarian involvement can be problematic. Whilst both blood tumor markers and use of immunohistochemical staining on tissue can help decide the origin of the tumor, this is done separately. This study looked at the blood and tissue marker profiles of 198 cases of disseminated malignancy to construct a model, which may help to determine tumor origin. The original histology material from 198 cases of disseminated intra-abdominal epithelial malignancy were reviewed, blind, and reassessed as to the likely site of origin. These cases had immunohistochemical (IHC) staining for cytokeratins (CK) 7 and 20, carcinoembryonic antigen (CEA) and CA125. Blood values for CEA and CA125 were also known at diagnosis. The histologic types of the tumors in this pilot study were of ovarian type morphologically in 130 cases (65.7%), nonovarian in 32 (16.1%), and not assigned in 36 cases (18.2%). The majority of the nonovarian cases were of mucinous type or too poorly differentiated to classify. Analysis showed an overall sensitivity and specificity of 93% and 69%, and positive predictive and negative predictive value of 92% and 71%, respectively, for a diagnosis of ovarian vs nonovarian origin using histology alone vs histology and IHC. Use of an ordinal regression developed a model which uses tissue staining for CK 7 and CEA along with blood levels of CEA to help determine the site of tumor origin.

The impact of driver distraction on road safety: results from a representative survey in two Australian states

OBJECTIVE

To quantify the prevalence and effects of distracting activities while driving.

DESIGN

Cross sectional driver survey.

SETTING

New South Wales and Western Australia, Australia.

PARTICIPANTS

1347 licensed drivers aged between 18 and 65 years. Data were weighted to reflect the corresponding driving population.

MAIN OUTCOME MEASURES

Prevalence of distracting activities while driving; perceived risks and adverse outcomes due to distractions.

RESULTS

The most common distracting activities during the most recent driving trip were lack of concentration (weighted percentage (standard error, SE) 71.8% (1.4%) of drivers); adjusting in-vehicle equipment (68.7% (1.5%)); outside people, objects or events (57.8% (1.6%)); and talking to passengers (39.8% (1.6%)). On average, a driver engaged in a distracting activity once every six minutes. One in five crashes (21%) during the last three years, involving one in 20 drivers (5.0% (0.7%)), was attributed to driver distraction based on self-report. In the population under study, this equated to 242,188 (SE 34,417) drivers. Younger drivers (18-30 years) were significantly more likely to report distracting activities, to perceive distracting activities as less dangerous, and to have crashed as a result.

CONCLUSIONS

Distracting activities while driving are common and can result in driving errors. Driver distraction is an important cause of crashes. Further research is needed to estimate the risk conferred by different distracting activities and the circumstances during which activities pose greatest risk. These results suggest that a strategy to minimize distracting activities while driving, with a focus on young drivers, is indicated.

Phone use and crashes while driving: A representative survey of drivers in two Australian states

OBJECTIVE

To explore the use and effects of using mobile phones while driving.

DESIGN

Cross-sectional survey.

SETTING

New South Wales and Western Australia, 20 October to 7 November 2003.

PARTICIPANTS

1347 licensed drivers aged 18 to 65 years. Data were weighted to reflect the corresponding driving population in each state.

MAIN OUTCOME MEASURES

Mobile phone use while driving (hand-held, hands-free and text messaging); adverse effects of use.

RESULTS

While driving, an estimated 57.3% +/- 1.5% of drivers have ever used a mobile phone and 12.4% +/- 1.0% have written text messages. Men, younger drivers and metropolitan residents were more likely to use a phone while driving and to report a higher frequency of use. Enforcement of hand-held phone restrictions was perceived to be low (69.0% +/- 1.5%) and an estimated 39.4% +/- 2.1% of people who phone while driving use a hand-held phone. Half of all drivers (50.1% +/- 1.6%) did not agree with extending the ban to include hands-free phones. Among drivers aged 18-65 years in NSW and WA, an estimated 45 800 +/- 16 466 (0.9% +/- 0.3%) have ever had a crash while using a mobile phone and, in the past year, 146 762 +/- 26 856 (3.0% +/- 0.6%) have had to take evasive action to avoid a crash because of their phone use.

CONCLUSIONS

Phone use while driving is prevalent and can result in adverse consequences, including crashes. Despite legislation, a significant proportion of drivers continue to use hand-held mobile phones while driving. Enhanced enforcement is needed.

Prevalence of helmet use among motorcycle riders in Vietnam

OBJECTIVES

To investigate the rate of helmet use among motorcycle drivers in Hai Duong province of Vietnam during winter/spring 2005, and to compare the rates of helmet use by road types.

METHOD

Population-based observational surveys.

RESULTS

16,560 motorcyclists were observed across 37 road sites (incorporating 5 road categories). The overall weighted average of helmet use for motorcyclists was 29.94%, with male drivers more likely to wear helmets than female drivers (odds ratio (OR) 1.64, 95% confidence interval (CI) 1.53 to 1.76). Male pillion passengers were less likely to wear helmets than female pillion passengers (OR 0.78, 95% CI 0.72 to 0.85). The number of adult drivers using helmets is larger as compared with that of young drivers (OR 8.56, 95% CI 5.93 to 12.19). The rates of helmet use were significantly higher (p<0.001) on compulsory roads and were 59.01%, 39.97%, 24.22%, 12.7% and 9.54% for national, provincial, district, commune and Hai Duong inner-city roads, respectively.

CONCLUSION

Helmet legislation has increased the rate of helmet use by motorcycle drivers on compulsory roads. Elsewhere, rate of helmet use is very low, indicating that in the absence of legislation and enforcement, motorcyclists in Vietnam will not wear a helmet.

Estimating population-based injury prevention practices

This study piloted a survey suitable to generate statewide prevalence estimates for injury prevention practices and/or behaviours. A number of prevalence estimates of injury prevention practices and/or behaviours were generated in the pilot. For example, the prevalence of a household smoke alarm was high (732/1000 households) and yet only 44% of households had tested the functionality of the alarm in the 12 months preceding the survey. Findings of this kind point to an increasing need for primary care practitioners to play a leading role in targeting preventive strategies for injury. In addition, the survey methods and approach highlight the value of such information to health departments and non-government agencies in terms of targeting priority injury risk behaviours and the evaluation of injury-related intervention programmes. The survey has been designed so the methods can be applied nationally and internationally.

In vivo macular pigment measurements: a comparison of resonance Raman spectroscopy and heterochromatic flicker photometry

AIM

To investigate whether two methods of measuring macular pigment-namely, heterochromatic flicker photometry (HFP) and resonance Raman spectroscopy (RRS)--yield comparable data.

METHODS

Macular pigment was measured using HFP and RRS in the right eye of 107 participants aged 20-79 years. Correlations between methods were sought and regression models generated. RRS was recorded as Raman counts and HFP as macular pigment optical density (MPOD). The average of the top three of five Raman counts was compared with MPOD obtained at 0.5 degrees eccentricity, and an integrated measure (spatial profile; MPODsp) computed from four stimulus sizes on HFP.

RESULTS

The coefficient of variation was 12.0% for MPODsp and 13.5% for Raman counts. MPODsp exhibited significant correlations with Raman counts (r = 0.260, p = 0.012), whereas MPOD at 0.5 degrees did not correlate significantly (r = 0.163, p = 0.118). MPODsp was not significantly correlated with age (p = 0.062), whereas MPOD at 0.5 degrees was positively correlated (p = 0.011). Raman counts showed a significant decrease with age (p = 0.002) and were significantly lower when pupil size was smaller (p = 0.015).

CONCLUSIONS

Despite a statistically significant correlation, the correlations were weak, with those in excess of 90% of the variance between MPODsp and Raman counts remaining unexplained, meriting further research.

Incidence and risk factors for injury in non-elite netball

This paper identifies the risk and protective factors for injury in non-elite netball. Three-hundred and sixty-eight non-elite netballers completed a baseline questionnaire at the commencement of the 1997 preseason. Participants were telephoned each month during the 1997 and 1998 playing seasons to provide details of their exposure at training and games and any injury experiences in the previous 4 weeks. The incidence of injury in this study was 14 injuries per 1000 player hours. The risk factors for injury were identified as: not warming up before a game (IRR 1.11, 95% CI 1.00-1.23) and not being open to new ideas (IRR 1.04, 95% CI 1.00-1.07). Training for 4 or more hours per week (IRR 0.66, 95% CI 0.45-0.98) and not sustaining an injury in the previous 12 months (IRR 0.58, 95% CI 0.43-0.79) were found to be protective against injury. The risk and protective factors for injury identified in this study can be used as the basis for the development of evidence-based injury prevention strategies that seek to reduce the risk of injury in sport. Injury prevention strategies should focus on the development of effective training programs that include netball-specific skills, activities and movements. Further investigation into the mechanisms associated with the risk and protective factors identified would provide further understanding of why these factors increase or decrease the risk of injury.

Injury profiles of Indigenous and non‐Indigenous people in New South Wales

OBJECTIVES

To compare the injury profiles of the Indigenous population in New South Wales with that of the non-Indigenous population.

DESIGN AND SETTING

Descriptive analysis of NSW Health data obtained from the Health Outcomes Information and Statistical Toolkit (HOIST) database. Hospitalisation data were collected for the period 1 July 1999 to 30 June 2003. Mortality data were collected for the period 1 January 1999 to 31 December 2002.

MAIN OUTCOME MEASURES

Hospitalisation and death rates due to injury by age, sex, injury mechanism and Indigenous status. Rate ratios for comparison between Indigenous and non-Indigenous populations.

RESULTS

Rates of death from injury were higher for all age groups in the Indigenous population, except people older than 65 years. Indigenous people aged 25-44 years were twice as likely to be hospitalised as their non-Indigenous counterparts (rate ratio [RR], 2.09; 95% CI, 2.03-2.14), and five times as likely to be hospitalised for interpersonal violence (RR, 5.19; 95% CI, 4.98-5.40).

CONCLUSION

The higher rates of injury-related hospitalisation and death in the Indigenous population in NSW are consistent with data reported for other parts of Australia. Of particular concern is the number of Indigenous deaths and hospitalisations due to interpersonal violence.

Further validation of the Daily Living Tasks Dependent on Vision: identification of domains

AIM

To examine the Daily Living Tasks Dependent on Vision (DLTV), a visual function questionnaire for domain structure, and redundancy.

METHOD

235 subjects underwent full ophthalmic assessment and completed the DLTV questionnaire by interview. Principal component analysis with varimax rotation and item response theory (IRT) were used to assign the items to domains. The internal consistency of each domain was examined using Cronbach's alpha. Redundancy was assessed by regressing each item in a domain against the remainder of items in that domain.

RESULTS

Four domains were identified. Domain 1 was formed by nine items, which after applying IRT were seen to be among the most difficult questions in the instrument. Domain 2 contained eight items, all of which fell in the easier half of the instrument on applying IRT. Domain 3 contained only three items, all of which were among the easier questions and appear to deal with peripheral vision function. Domain 4 consisted of two items dealing with adaptation to light and dark conditions. Cronbach's alpha for each domain was 0.96, 0.93, 0.73, 0.66. Redundancy was found to be present in domain 1, which was therefore reduced by two items, with little effect on internal consistency.

CONCLUSIONS

The authors believe using the domains identified in this report will optimise the information provided by patients on their ability to function on visually demanding tasks.

Role of mobile phones in motor vehicle crashes resulting in hospital attendance: a case-crossover study

OBJECTIVES

To explore the effect of drivers' use of mobile (cell) phones on road safety.

DESIGN

A case-crossover study.

SETTING

Perth, Western Australia.

PARTICIPANTS

456 drivers aged > or = 17 years who owned or used mobile phones and had been involved in road crashes necessitating hospital attendance between April 2002 and July 2004.

MAIN OUTCOME MEASURE

Driver's use of mobile phone at estimated time of crash and on trips at the same time of day in the week before the crash. Interviews with drivers in hospital and phone company's records of phone use.

RESULTS

Driver's use of a mobile phone up to 10 minutes before a crash was associated with a fourfold increased likelihood of crashing (odds ratio 4.1, 95% confidence interval 2.2 to 7.7, P < 0.001). Risk was raised irrespective of whether or not a hands-free device was used (hands-free: 3.8, 1.8 to 8.0, P < 0.001; hand held: 4.9, 1.6 to 15.5, P = 0.003). Increased risk was similar in men and women and in drivers aged > or = 30 and < 30 years. A third (n = 21) of calls before crashes and on trips during the previous week were reportedly on hand held phones.

CONCLUSIONS

When drivers use a mobile phone there is an increased likelihood of a crash resulting in injury. Using a hands-free phone is not any safer.

Modelling bivariate count series with excess zeros

Bivariate time series of counts with excess zeros relative to the Poisson process are common in many bioscience applications. Failure to account for the extra zeros in the analysis may result in biased parameter estimates and misleading inferences. A class of bivariate zero-inflated Poisson autoregression models is presented to accommodate the zero-inflation and the inherent serial dependency between successive observations. An autoregressive correlation structure is assumed in the random component of the compound regression model. Parameter estimation is achieved via an EM algorithm, by maximizing an appropriate log-likelihood function to obtain residual maximum likelihood estimates. The proposed method is applied to analyze a bivariate series from an occupational health study, in which the zero-inflated injury count events are classified as either musculoskeletal or non-musculoskeletal in nature. The approach enables the evaluation of the effectiveness of a participatory ergonomics intervention at the population level, in terms of reducing the overall incidence of lost-time injury and a simultaneous decline in the two mean injury rates.

Visual functioning and quality of life in the SubFoveal Radiotherapy Study (SFRADS): SFRADS report 2

AIMS

To determine whether or not self reported visual functioning and quality of life in patients with choroidal neovascularisation caused by age related macular degeneration (AMD) is better in those treated with 12 Gy external beam radiotherapy in comparison with untreated subjects.

METHODS

A multicentre single masked randomised controlled trial of 12 Gy of external beam radiation therapy (EBRT) delivered as 6 x 2 Gy fractions to the macula of an affected eye versus observation. Patients with AMD, aged 60 years or over, in three UK hospital units, who had subfoveal CNV and a visual acuity equal to or better than 6/60 (logMAR 1.0).

METHODS

Data from 199 eligible participants who were randomly assigned to 12 Gy teletherapy or observation were available for analysis. Visual function assessment, ophthalmic examination, and fundus fluorescein angiography were undertaken at baseline and at 3, 6, 12, and 24 months after study entry. To assess patient centred outcomes, subjects were asked to complete the Daily Living Tasks Dependent on Vision (DLTV) and the SF-36 questionnaires at baseline, 6, 12, and 24 months after enrolment to the study. Cross sectional and longitudinal analyses were conducted using arm of study as grouping variable. Regression analysis was employed to adjust for the effect of baseline co-variates on outcome at 12 months and 24 months.

RESULTS

Both control and treated subjects had significant losses in visual functioning as seen by a progressive decline in mean scores in the four dimensions of the DLTV. There were no statistically significant differences between treatment and control subjects in any of dimensions of the DLTV at 12 months or 24 months after study entry. Regression analysis confirmed that treatment status had no effect on the change in DLTV dimensional scores.

CONCLUSIONS

The small benefits noted in clinical measures of vision in treated eyes did not translate into better self reported visual functioning in patients who received treatment when compared with the control arm. These findings have implications for the design of future clinical trials and studies.

Evaluating the effectiveness of a participatory ergonomics approach in reducing the risk and severity of injuries from manual handling

Manual handling is the greatest contributor to non-fatal injury and disease in the workplace, commonly accounting for one-third of national injury counts. Interventional strategies that have focused on selecting or modifying the worker have been ineffective in reducing injury risk. In recent times, participatory ergonomics has been widely adopted as a process to reduce the risk of injury from manual handling but it is not well validated as an intervention. This study evaluated the effectiveness of a participatory ergonomics risk assessment approach in reducing the rate and severity of injuries from manual and non-manual handling sustained by a cohort of 137 cleaners within a hospital setting. The date of injury and the workers' compensation claim cost and hours lost from work were obtained for each injury incurred during the 4-year pre-intervention and 3-year intervention period. The age, gender and hours worked were ascertained for every cleaner whether injured or not. Using generalized linear mixed modelling analysis, reductions of rate of injury by two-thirds, workers' compensation claim costs by 62% and hours lost by 35% for manual handling injuries were found to be associated with the intervention period. Although the cleaners experienced a significant intervention period reduction in non-manual handling injury rate, the corresponding changes in severity of injury were not significant. The success of the intervention supports the adoption of a participatory ergonomics approach in reducing the rate and consequence of injuries in the workplace.

Steering in the right direction? Young drivers and road trauma

We need restrictions on night driving and peer passenger numbers for novice drivers

Reduced vision in older adults with age related macular degeneration interferes with ability to care for self and impairs role as carer

AIM

To study the relation between visual impairment and ability to care for oneself or a dependant in older people with age related macular degeneration (AMD).

METHOD

Cross sectional study of older people with visual impairment due to AMD in a specialised retinal service clinic. 199 subjects who underwent visual function assessment (fully corrected distance and near acuity and contrast sensitivity in both eyes), followed by completion of a package of questionnaires dealing with general health status (SF36), visual functioning (Daily Living Tasks Dependent on Vision, DLTV) and ability to care for self or provide care to others. The outcome measure was self reported ability to care for self and others. Three levels of self reported ability to care were identified--inability to care for self (level 1), ability to care for self but not others (level 2), and ability to care for self and others (level 3).

RESULTS

People who reported good general health status and visual functioning (that is, had high scores on SF36 and DLTV) were more likely to state that they were able to care for self and others. Similarly people with good vision in the better seeing eye were more likely to report ability to care for self and others. People with a distance visual acuity (DVA) worse than 0.4 logMAR (Snellen 6/15) had less than 50% probability of assigning themselves to care level 3 and those with DVA worse than 1.0 logMAR (Snellen 6/60) had a probability of greater than 50% or for assigning themselves to care level 1. Regression analyses with level of care as the dependent variable and demographic factors, DLTV subscales, and SF36 dimensions as the explanatory variables confirmed that the DLTV subscale 1 was the most important variable in the transition from care level 3 to care level 2. The regression analyses also confirmed that the DLTV subscale 2 was the most important in the transition from care level 3 to care level 1.

CONCLUSIONS

Ability to care for self and dependants has a strong relation with self reported visual functioning and quality of life and is adversely influenced by visual impairment. The acuity at which the balance of probability shifts in the direction of diminished ability to care for self or others is lower than the level set by social care agencies for provision of support. These findings have implications for those involved with visual rehabilitation and for studies of the cost effectiveness of interventions in AMD.

The effect of nicotine on basophil histamine release

BACKGROUND

Changes in the immune and inflammatory response are induced by smoking tobacco but underlying mechanisms remain to be elucidated.

OBJECTIVE

This study investigated the effect of nicotine agonists on histamine release from human basophils.

METHODS

Peripheral blood basophils were obtained from healthy volunteers. The effect of the nicotine agonists [-]-1-methyl-2-[3-pyridyl]pyrrolidine and (+)-nicotine di-p-toluoyltartrate salt on cell viability and anti-IgE induced histamine release was investigated.

RESULTS

Cell viability was not altered by preincubation with the agents for 15 min. Anti-IgE induced histamine release was significantly inhibited by preincubation (15 min, 37 degrees C) with [-]-1-methyl-2-[3-pyridyl]pyrrolidine at the highest concentration tested 10(-)3 M (p<0.01). Preincubation (15 min, 37 degrees C) with (+)-nicotine di-p-toluoyltartrate salt significantly inhibited anti-IgE induced histamine release at 10(-3)M and 10(-5) M (p<0.05).

CONCLUSIONS

This study has demonstrated that nicotine agonists inhibit histamine release from human basophils. Further studies examining the effect of smoking on basophil activation are required.

Community-based study of the association of high myopia in children with ocular and systemic disease

PURPOSE

High myopia in childhood is associated with important ocular and systemic conditions. However in the UK, high myopia in early childhood is not specifically identified in current ophthalmology, optometry, or orthoptic protocols for screening, referral, or investigation. An ongoing study in the West Midlands, UK, is investigating high myopia presenting to community health care clinics with the aim of compiling guidelines for assessment and subsequent referral.

METHODS

Children with high myopia were identified from community optometric and orthoptic sources and invited for an ophthalmology and optometry examination to ascertain possible ocular or systemic disease.

RESULTS

High myopia with no associated ocular or systemic condition was present in 15 (56%) of the children. In seven children (25%), associated ocular problems were found including unrecognized retinal dystrophies and amblyopia. Systemic disorders associated with high myopia were found in five children (19%) and included Sticklers syndrome, Weill-Marchesani syndrome, and homocystinuria. In one child, the diagnosis made before this study was found to be incorrect, and in another child, the results were inconclusive. In two cases, the diagnosis of a systemic condition in the child led to the identification of the disease in at least one relative.

CONCLUSIONS

There is a high prevalence of ocular and systemic abnormality in young children seen in the community. Optometric and ophthalmologic assessment of children less than 10 years with myopia > or =5 D is likely to identify significant ocular or systemic disease, a proportion of which will respond to medical intervention. Detection and prompt referral of these cases by community health care services may be expected to prolong vision and possibly life expectancy.

CNV subtype in first eyes predicts severity of ARM in fellow eyes

AIM

To examine the relation between the type of choroidal neovascularisation (CNV) in the first eye and age related maculopathy (ARM) severity in the fellow eye.

METHODS

Colour fundus photographs and fluorescein angiograms from 67 subjects with a clinical diagnosis of CNV in one eye were scrutinised. CNV was classified as wholly classic, predominantly classic, minimally classic, or occult based on the proportion of classic leakage within the lesion. ARM changes in the fellow eye were assigned a severity stage using the system described by the Rotterdam Eye Study. Logistic regression analysis was employed to examine the association between CNV subtype and ARM stage.

RESULTS

Of subjects with classic or predominantly classic CNV in the first eye 78% exhibited least no or early ARM features in the fellow eye. By contrast, 85% of subjects with minimally classic or occult CNV in the first eye exhibited more advanced ARM features in the fellow eye. Kruskall-Wallis one way ANOVA by ranks showed that this was highly significant (p = 0.002). Logistic regression analysis showed that as the proportion of occult CNV increased in the first eye, fellow eyes of subjects in this category were more likely to have been assigned to a higher ARM stage (p = 0.019). The area occupied by the CNV in the first eye also influenced severity of ARM changes in the fellow eye.

CONCLUSION

The type and extent of CNV in the first affected eye has a distinct relation to ARM severity in the fellow eye. Fellow eyes of subjects with minimally classic or occult CNV in the first affected eye show widespread ARM changes suggestive of retinal pigment epithelial dysfunction. These findings suggest that classic CNV may be focal disease while occult CNV is essentially a more widespread retinal pigment epithelial disorder.

Childhood drowning: barriers surrounding private swimming pools

OBJECTIVE

To investigate the causes of child drowning and determine the need for changes in the legislation as well as improvements to the inspection and enforcement of current legislation related to barriers surrounding private swimming pools.

METHODS

There were 3 stages to the study: a retrospective review of coroner's data, an audit of swimming pool inspections, and in-depth interviews with swimming pool inspectors in Western Australia. The incidence of childhood drowning (per population) and compliance rates of swimming pools (per 1000 swimming pools) to the legislation were measured.

RESULTS

During the 12-year observational period (1988-2000) 50 children younger than 5 years drowned in private swimming pools in Western Australia with an overall incidence of drowning of 4.4 per 100 000 children per year. Sixty-eight percent of drownings occurred in pools that did not have 4-sided fencing with an almost 2-fold increased risk (incidence rate ratio: 1.78; 95% confidence interval: 1.40-1.79) of a child's drowning in a swimming pool with 3-sided versus 4-sided fencing. The compliance rate of swimming pools (compliance to the current legislation) at first inspection was approximately 400 per 1000 swimming pools.

CONCLUSIONS

Almost two thirds of the swimming pools in which children drowned had only 3-sided fencing. With a combination of a change in legislation, enhanced inspection processes, and public education, the incidence of drowning in private swimming pools in Western Australia could be reduced in the coming years.

Smoking, atopy and certain furry pets are major determinants of respiratory symptoms in children: the International Study of Asthma and Allergies in Childhood Study (Ireland)

BACKGROUND

Environmental, cultural and health care differences may account for variation among countries in the prevalence of asthma and respiratory symptoms in teenagers.

OBJECTIVE

To examine the prevalence of respiratory symptoms and the level of diagnosis, and to compare determinants of asthma and severe wheeze in two countries.

METHODS

Self-completion questionnaires based on the International Study of Asthma and Allergies in Childhood (ISAAC) protocol were provided to school children in Ireland (Republic and Northern Ireland). In the Republic of Ireland, all children in classes largely aged 13-14 years from 30 post-primary schools were selected by random sampling stratified by school size, composition and Health Board in Spring 1995. In Northern Ireland, all children largely aged 13-14 years of age from 26 post-primary schools were selected by random sampling stratified by school type, composition and Education and Library Board in Spring 1996.

RESULTS

Questionnaires were completed by 2,364 children from Northern Ireland and 2,671 from the Republic, about 90% of those eligible to participate. The prevalences of wheeze at various levels of severity, of diagnosed asthma and of treated wheeze were very similar in Northern Ireland and the Republic of Ireland. A significant proportion of those reporting more severe symptomatology (four or more attacks of wheeze in the past 12 months and/or one or more nights disturbed and/or moderate or greater disruption of daily activities and/or speech restriction due to wheeze) had been neither diagnosed nor treated for asthma (20-37%). To investigate the determinants of the more severe symptomatology of asthma or treated wheeze a series of stepwise multiple regression analyses was performed. A history of atopy, cigarette smoking, the possession of a furry pet other than a dog or cat and age were each independently associated with severe wheeze, whilst atopy, a furry pet (as above) and gender were each independently associated with asthma or treated wheeze.

CONCLUSIONS

Cigarette smoking is closely associated with the reporting of significant respiratory symptoms together with atopy and exposure to furry pets. Some 20-37% of severe symptoms were neither diagnosed nor treated as asthma.

Visual outcomes in the subfoveal radiotherapy study: a randomized controlled trial of teletherapy for age-related macular degeneration

OBJECTIVE

To determine whether teletherapy with 6-mV photons can reduce visual loss in patients with subfoveal choroidal neovascularization in age-related macular degeneration.

DESIGN

A multicenter, single-masked, randomized controlled trial of 12 Gy of external beam radiation therapy delivered to the macula of an affected eye vs observation only.

SETTING

Three United Kingdom-based hospital units.

PARTICIPANTS

Patients with age-related macular degeneration, aged 60 years and older, who had subfoveal choroidal neovascularization and a visual acuity of 20/200 (logMAR 1.0) or better.

METHODS

Two hundred three patients were randomly assigned to radiotherapy or observation. Treatment was undertaken at designated radiotherapy centers, and patients assigned to the treatment group received a total dosage of 12 Gy of 6-mV photons in 6 fractions. Follow-up was scheduled at 3, 6, 12, and 24 months. After excluding protocol violators, the data from 199 patients were analyzed.

MAIN OUTCOME MEASURES

The primary outcome measure was mean loss of distance visual acuity in the study eye at 12 and 24 months. Other outcome variables analyzed were near visual acuity and contrast sensitivity. The proportions of patients losing 3 or more or 6 or more lines of distance and near acuity and 0.3 or more or 0.6 or more log units of contrast sensitivity at each follow-up were also analyzed.

RESULTS

At all time points, mean distance visual acuity was better in the radiotherapy-treated group than in the control group, but the differences did not reach statistical significance. At 24 months, analysis of the proportions of patients with loss of 3 or more (moderate) (P =.08) or 6 or more (severe) (P =.29) lines of distance vision showed that fewer treated patients had severe losses, but there was no statistically significant difference between groups. For near visual acuity, although there was no evidence of treatment benefit at 12 and 24 months, a significant difference in favor of treatment was present at 6 months (P =.048). When analyzed by the proportions of patients losing 3 lines of contrast sensitivity, there was a significant difference in favor of treatment at 24 months (P =.02). No adverse retinal effects were observed during the study, but transient disturbance of the precorneal tear film was noted in treated patients.

CONCLUSION

The results of the present trial do not support the routine clinical use of external beam radiation therapy in subjects with subfoveal choroidal neovascularization in age-related macular degeneration.

Modeling young driver motor vehicle crashes: data with extra zeros

Much of the data collected on motor vehicle crashes is count data. The standard Poisson regression approach used to model this type of data does not take into account the fact there are few crash events and hence, many observed zeros. In this paper, we applied the zero-inflated Poisson (ZIP) model (which adjusts for the many observed zeros) and the negative binomial (NB) model to analyze young driver motor vehicle crashes. The results of the ZIP regression model are comparable to those from fitting a NB regression model for general over-dispersion. The findings highlight that driver confidence/adventurousness and the frequency of driving prior to licensing are significant predictors of crash outcome in the first 12 months of driving. We encourage researchers, when analyzing motor vehicle crash data, to consider the empirical frequency distribution first and to apply the ZIP and NB models in the presence of extra zeros due, for example, to under-reporting.

Improvements in measures of vision and self-reported visual function after cataract extraction in patients with late-stage age-related maculopathy

PURPOSE

A recent study indicated that patients with cataracts and early age-related maculopathy may benefit from cataract extraction. To ascertain whether cataract extraction in the presence of concurrent advanced age-related maculopathy was also associated with a clear benefit, we studied visual function and self-reported visual functioning in a cohort of 12 patients pre- and post-phakoemulsification. METHODS. All 12 patients had a diagnosis of advanced age-related maculopathy in the eye scheduled for cataract surgery. Preoperative assessment included refraction and recording of best corrected distance and near acuity and contrast sensitivity in both eyes. The Daily Living Tasks Dependent on Vision questionnaire was administered. After phakoemulsification and intraocular lens implantation, all patients were reviewed and assessed.

RESULTS

After surgery, improvement in acuity was recorded in nine operated eyes, whereas acuity remained unchanged in three eyes. Improvement in contrast sensitivity in the operated eye occurred in 10 patients, but in two patients contrast was reduced postoperatively. In terms of self-reported visual functioning, improvement in the ability to undertake many daily living tasks dependent on vision was recorded after cataract surgery.

CONCLUSIONS

Significant improvements in specific areas of self-reported visual functioning and measures of vision were recorded after cataract surgery. During the follow-up period, none of the operated eyes suffered a fall in visual acuity. There was also no evidence of worsening of the pre-existing macular lesion as judged by clinical examination and fundus photography.

Behavioural factors as predictors of motor vehicle crashes: differentials between young urban and rural drivers

OBJECTIVE

To describe the driver and behavioural factors that predispose young drivers to crash in the first 12 months of driving and to compare whether these factors differ between young urban and rural drivers.

METHODS

A cohort comprising 1,796 newly licensed urban and rural drivers from Western Australia was recruited and followed over the first 12 months of driving. Using Cox proportional hazard analysis, driver and behavioural factors were assessed to determine whether they predicted the likelihood of a crash.

RESULTS

The incidence rate for a motor vehicle crash was marginally higher for urban drivers compared with rural drivers (Urban: IR=4.2/10,000 driving days; Rural: IR=3.7/10,000 driving days). There was no significant difference in the time to crash between urban and rural drivers. Two factors, namely the frequency of driving before obtaining a learner-driver permit and the driver's level of risk taking, were significantly associated with a motor vehicle crash in the first year of driving.

CONCLUSION

Irrespective of whether the driver is licensed in a rural or urban area, high risk-taking drivers are at an elevated risk of a motor vehicle crash in the first 12 months of driving.

IMPLICATIONS

Aspects of Graduated Driver Training and Licensing Programs (GDTLP) could be effective in targeting this at-risk group.

Validation of an outcome scale for use in adult psychiatric practice

OBJECTIVE

To clarify the usefulness, acceptability, sensitivity, and validity of version 4 of the Health of the Nation Outcome Scale (HoNOS), a scale developed to meet the requirement for a clinically acceptable outcome scale for routine use in mental illness services.

DESIGN

Patients with a range of mental illnesses were rated on the HoNOS at the beginning and end of an episode by interviews with mental health professionals.

SUBJECTS

934 patients from eight diagnostic categories were rated by 129 mental health professionals at 17 sites; 250 were also rated on a range of comparison scales.

OUTCOME MEASURES

Comparison of patients' scores at the beginning and end of an episode using individual item scores, dimensional subscores, and the total score.

RESULTS

HoNOS scores decreased by almost 50% between the beginning and end of episodes. They varied with the severity of the setting and discriminant analysis showed that the HoNOS had a moderate level of discriminatory power. Correlation analysis showed acceptable levels of agreement with independent scales, although the accuracy of ratings of some items at the beginning of an episode was affected by information deficits.

CONCLUSION

The findings indicate that HoNOS is sensitive to change across time and to differences in illness type and severity, and has a sufficient degree of both construct and criterion related validity to fulfil the requirements of a mental health outcome scale for routine use in clinical settings.

Sport, age, and sex specific incidence of sports injuries in Western Australia

OBJECTIVE

To describe the trends in recreational sports injury in Perth, Western Australia.

DESIGN

A prospective cohort study of sports injuries during the 1997 winter season (May to September).

SETTING

Sample of Australian football, field hockey, basketball, and netball players from the Perth metropolitan area, Western Australia.

METHODS

A cohort of sports participants was followed over the five month winter sports season. Before the season, participants completed a baseline questionnaire and during the season were interviewed every four weeks by telephone.

RESULTS

Overall, 92% of participants (n = 1391) who completed a baseline questionnaire completed at least one follow up telephone interview. About half (51%) of the cohort sustained one or more injuries during the winter season accounting for a total of 1034 injuries. Most injuries were of moderate (58%, n = 598) or minor (40%, n = 412) severity, with only 3% (n = 24) requiring emergency department treatment or a hospital stay. The injury incidence rate was greatest for football (20.3/1000 hours of participation), similar for field hockey and basketball (15.2/1000 hours and 15.1/1000 hours respectively), and lowest for netball (12.1/1000 hours). The incidence of injury was greatest in the first four weeks of the season, and participants aged between 26 and 30 years had about a 55% greater risk of injury than those aged less than 18 years.

CONCLUSIONS

This is one of the first studies to show that recreational sports are safe. Although the likelihood of injury was greatest in the first month of the season, few injuries required admission to hospital or emergency department treatment. A greater emphasis on prevention in the early part of the season should help to reduce the elevated incidence of injury found at this time.