Comparing estimates of road traffic deaths and non-fatal road traffic injuries in Cambodia.

INTRODUCTION: Timely, accurate and detailed information about traffic injuries are essential for managing national road safety programmes. However, there is considerable under-reporting in official statistics of many low and middle-income countries (LMICs) and large discrepancies between estimates from the Global Burden of Disease (GBD) study and WHO's Global Health Estimates (GHE). We compared all sources of epidemiological information on traffic injuries in Cambodia to guide efforts to improve traffic injury statistics. METHODS: We estimated the incidence of traffic deaths and injuries and household ownership of motor vehicles in Cambodia from nationally representative surveys and censuses. We compared findings with GDB and GHE estimates. RESULTS: We identified seven sources for estimating traffic deaths and three for non-fatal injuries that are not included as data sources in GBD and GHE models. These sources and models suggest a fairly consistent estimate of approximately 3100 deaths annually, about 50% higher than official statistics, likely because most hospital deaths are not recorded. Surveys strongly suggest that the vehicle fleet is dominated by motorcycles, which is not consistent with GBD estimates that suggest similar numbers of motorcyclist and vehicle occupant deaths. Estimates of non-fatal injuries from health surveys were about 7.5 times official statistics and 1.5 times GBD estimates. CONCLUSION: Including local epidemiological data sources from LMICs can help reduce uncertainty in estimates from global statistical models and build trust in estimates among local stakeholders. Such analysis should be used as a benchmark to assess and strengthen the completeness of reporting of the national surveillance system.

Availability of population-level data sources for tracking the incidence of deaths and injuries from road traffic crashes in low-income and middle-income countries.

INTRODUCTION: Tracking progress towards Sustainable Development Goal (SDG) 3·6 of reducing traffic deaths and serious injuries poses a measurement challenge in most low-income and middle-income countries (LMICs) due to large discrepancies between reported official statistics and estimates from global health measurement studies. We assess the extent to which national population censuses and health surveys can fill the information gaps. METHODS: We reviewed questionnaires for nationally representative surveys and censuses conducted since 2000 in LMICs. We identified sources that provide estimates of household ownership of vehicles, incidence of traffic deaths and non-fatal injuries, and prevalence of disability. RESULTS: We identified 802 data sources from 132 LMICs. Sub-Saharan African countries accounted for 43% of all measurements. The number of measurements since 2000 was high, with 97% of the current global LMIC population having at least one measurement for vehicle ownership, 77% for deaths, 90% for non-fatal injuries and 50% for disability due to traffic injuries. Recent data (since 2010) on traffic injuries were available from far fewer countries (deaths: 21 countries; non-fatal injuries: 62 and disability: 12). However, there were many more countries with recent data on less-specific questions about unintentional or all injuries (deaths: 41 countries, non-fatal: 87, disability: 32). CONCLUSION: Traffic injuries are substantially underreported in official statistics of most LMICs. National surveys and censuses provide a viable alternative information source, but despite a large increase in their use to monitor SDGs, traffic injury measurements have not increased. We show that relatively small modifications and additions to questions in forthcoming surveys can provide countries with a way to benchmark their existing surveillance systems and result in a substantial increase in data for tracking road traffic injuries globally.

An implicit non-self-report measure of attitudes to speeding: development and validation.

Speeding is a major contributor to road trauma and attitudes toward speeding are hypothesised to be a key determinant of the behaviour. Attitudinal research is limited by reliance on self-report measures and the attendant possibility of reporting biases. The Implicit Association Test (IAT) aims to measure attitudes without reliance on self-report, by assessing the association between a target-concept and an evaluation, in terms of reaction time for compatible versus non-compatible pairings. The present research aimed to develop and evaluate an IAT to measure attitudes to speeding. Forty-five licensed drivers completed the speed-related IAT, and drove a driving simulator. Participants also completed a questionnaire that assessed self-reported attitudes to speeding, and several variables theoretically related to attitudes, including speeding behaviour. Observed IAT results suggested that attitudes toward speeding are negative, and were generally consistent with results derived from the simulated driving and self-reported behaviours, beliefs, and attitudes. Thus, the speed-related IAT appears to be a valid measure of attitudes toward speeding, which might be used to measure attitudes in road safety research without reliance on self-report.

The effects of training impulse control on simulated driving.

There is growing interest in young driver training that addresses age-related factors, including incompletely developed impulse control. Two studies investigated whether training of response inhibition can reduce risky simulated driving in young drivers (aged 16-24 years). Each study manipulated aspects of response inhibition training then assessed transfer of training using simulated driving measures including speeding, risky passing, and compliance with traffic controls. Study 1 (n = 65) used a Go/No-go task, Stop Signal Task and a Collision Detection Task. Designed to promote engagement, learning, and transfer, training tasks were driving-relevant and adaptive (i.e. difficulty increased as performance improved), included performance feedback, and were distributed over five days. Control participants completed matching "filler" tasks. Performance on trained tasks improved with training, but there was no significant improvement in simulated driving. Study 2 enhanced response inhibition training using Go/No-go and SST tasks, with clearer performance feedback, and 10 days of training. Control participants completed testing only, in order to avoid any possibility of training response inhibition in the filler tasks. Again performance on trained tasks improved, but there was no evidence of transfer of training to simulated driving. These findings suggest that although training of sufficient interest and duration can improve response inhibition task performance, a training schedule that is likely to be acceptable to the public does not result in improvements in simulated driving. Further research is needed to investigate whether response inhibition training can improve risky driving in the context of real-world motivations for risky driving.

Misunderstanding of right-of-way rules at various pedestrian crossing types: observational study and survey.

Misunderstanding of right-of-way rules may contribute to pedestrian trauma, especially at crossings where pedestrian and traffic signals appear to give contradictory messages. Two thousand eight hundred and fifty-four pedestrians were observed crossing at signal-controlled intersections to compare attention to traffic for different combinations of pedestrian and traffic signals. In addition, a survey was conducted at signal-controlled intersections and nearby car parks in metropolitan and rural areas. Five hundred and seventy-four participants took the role of pedestrian or driver when responding to questions regarding beliefs about pedestrian right-of-way for a range of situations at signal-controlled crossings, zebra crossings, and unmarked sections of road (specifically: alone, with pedestrian refuge, or paved). Results suggest that at signal-controlled crossings pedestrian right-of-way is erroneously thought to be influenced by the pedestrian signal. Many respondents thought that a pedestrian refuge or paving gave a pedestrian right-of-way at an otherwise unmarked section of road. In many situations more than 20% of both drivers and pedestrians reported that they would take right-of-way. Pedestrian crossing types should be rationalised, and education should be provided regarding rules and responsibilities at available crossings.

A challenge to the assumed generalizability of prediction and countermeasure for risky driving: different factors predict different risky driving behaviors.

In road safety, it may be debated whether all risky behaviors are sufficiently similar to be explained by similar factors. The often assumed generalizability of the factors that influence risky driving behaviors has been inadequately tested. Study 1 (N=116) examined the role of demographic, personality and attitudinal factors in the prediction of a range of risky driving behaviors, for young drivers. Results illustrated that different driving behaviors were predicted by different factors (e.g., speeding was predicted by authority--rebellion, while drink driving was predicted by sensation seeking and optimism bias). Study 2 (N=127) examined the generalizability of these results to the general driving population. Study 1 results did not generalize. Predictive factors remained behavior-specific, but different predictor-behavior relationships were observed in the community sample. Overall, results suggest that future research and practice should focus on a multi-factor framework for specific risky driving behaviors, rather than assuming generalizability across behaviors and driving populations.

Complaint data as an index of annoyance--theoretical and methodological issues.

Complaining constitutes one facet of all reactions to noise annoyance and is one way to cope with annoyance due to aircraft noise. In order to value and to establish the usefulness of complaint data as an index of annoyance, four questions need to be answered: Which factors lead annoyed residents to complain about aircraft noise or related issues? Which factors keep annoyed residents from complaining? Are the existing ways to handle annoyance adequate and efficient (e.g. keeping track of complaints, reaction to complains, kinds of complaint services)? Which are new ways to handle annoyance adequately and efficiently? In this paper a first attempt to answer these questions is made. Obviously, complaint data do not reflect noise annoyance in the surroundings of airports to the full extent as there are residents living in affected areas who do not complain, as well as residents living in areas with relatively low noise levels who complain. Also there is a large group of people who declare to be highly annoyed and yet, they do not lodge any complaint. Possible intervening factors are gathered that determine if an annoyed resident takes action and complains. It was found that noise levels per se are not the crucial factor for residents' decisions to complain or not to complain. Personal as well as feasibility factors play a vital role. Yet, the ongoing controversy on the relation between annoyance and complaint behaviour seems not resolved yet. However, complaint behaviour seems to be influenced by various aspects and complaint data consequently cannot be accepted as an accurate measure of public annoyance. Further research is required to address the preferred method of handling reaction to noise and the extent to which complaint itself helps with coping, for different groups of residents.

A follow-up study of effects of chronic aircraft noise exposure on child stress responses and cognition.

BACKGROUND: Children are a high-risk group vulnerable to the effects of chronic aircraft noise exposure. This study examines the effects of aircraft noise exposure on children's health and cognition around London Heathrow airport and tests sustained attention as an underlying mechanism of effects of noise on reading and examines the way children adapt to continued exposure to aircraft noise. METHODS: In this repeated measures epidemiological field study, the cognitive performance and health of 275 children aged 8-11 years attending four schools in high aircraft noise areas (16-h outdoor Leq > 66 dBA) was compared with children attending four matched control schools exposed to lower levels of aircraft noise (16-h outdoor Leq < 57 dBA). The children first examined at baseline were examined again after a period of one year at follow-up. Health questionnaires and cognitive tests were group administered to the children in the schools. RESULTS AND CONCLUSIONS: At follow-up chronic aircraft noise exposure was associated with higher levels of annoyance and perceived stress, poorer reading comprehension and sustained attention, measured by standardized scales after adjustment for age, social deprivation and main language spoken. These results do not support the sustained attention hypothesis previously used to account for the effects of noise on cognition in children. The reading and annoyance effects do not habituate over a one-year period and do not provide strong evidence of adaptation.

Stress and consumption: inescapable shock, neophobia, and quinine finickiness in rats.

Exposure to inescapable shock has been shown to result in reduced consumption of quinine in water (the finickiness effect) in rats. In the present experiment, (a) a clear difference in finickiness occurred between male adult rats exposed to inescapable shock and those exposed to escapable shock (the first such demonstration), (b) finickiness was reinstated 20 days later, and (c) finickiness was eliminated by quinine exposure prior to treatment. The first 2 results support the role of uncontrollability and/or unpredictability in finickiness and extend its potential impact to long-term consequences. This allows greater potential for the modeling of long-term effects, such as eating disorders and depression in humans. The finding that preexposure to quinine eliminated finickiness is contrary to current accounts of the effect. Accounts of finickiness are proposed in terms of classically conditioned aversions, bitterness, and neuropeptide control of ingestion.

Inhibition of adenosine deaminase by erythro-9-(2-hydroxy-3-nonyl)adenine (EHNA) mimics the effect of inescapable shock on escape learning in rats.

Three experiments examined the role of adenosine neuroregulation in the production of shuttle-escape deficits caused by prior exposure to inescapable electric shock in rats (learned helplessness). Intracerebroventricular administration of erythro-9-(2-hydroxy-3-nonyl)adenine (EHNA), a selective adenosine deaminase inhibitor, mimicked the effect of earlier inescapable shock at a dose of 2.5 microM in previously restrained rats. Performance deficits produced by EHNA or by earlier exposure to inescapable shock were reversed by intraperitoneal injection of 10 mg/kg caffeine, an adenosine receptor antagonist. Finally, preexposure to an ineffective number of shocks interacted in synergy with an ineffective pretest dose (1.0 microM) of EHNA to maximize shuttle-escape latencies. These data implicate endogenous adenosine neuroregulation as a proximate mechanism in learned helplessness and conservation-withdrawal.

Escape deficits induced by inescapable shock and metabolic stress are reversed by adenosine receptor antagonists.

We examined the relationship between metabolic stress, brain adenosine regulation, and the learned helplessness effect in four experiments in rats. Glucoprivation and metabolic inhibition were induced by treating previously restrained (nonshocked) rats with 2-deoxy-D-glucose (2DG) shortly before escape testing. Experiment 1 demonstrated that 2-deoxy-D-glucose impairs escape performance in a dose-dependent manner. Experiment 2 showed that 2-deoxy-D-glucose and shock induced escape deficits are completely reversed by peripheral administration of the adenosine receptor antagonist caffeine. This result indicates that both inescapable shock and 2-deoxy-D-glucose result in compensatory adenosine regulation which, in turn, mediates the behavioral impairment. Experiment 3 determined that 8-[p-sulfophenyl]-theophylline, a peripheral adenosine receptor antagonist, fails to reverse the escape deficit resulting from metabolic stress, whereas centrally acting theophylline does. Experiment 4 showed that the behavioral impairments from both 2-deoxy-D-glucose and inescapable shock are reversed by intracranial ventricular (icv) caffeine treatment. The results of Experiments 3 and 4 indicate that the enhanced adenosine regulation and the ensuing performance deficit resulting from 2-deoxy-D-glucose treatment occurred in the central nervous system. These data are discussed in terms of the metabolic demands of neuronal over-activation during escape testing in inescapably shocked rats and the loss of normal behavioral function due to compensatory adenosine regulation in the brain.

Reconsideration of the role of competing responses in demonstrations of the interference effect (learned helplessness).

In Experiment 1a, rats trained to escape shock by performing a 2-s inactive response were less impaired on a subsequent 2-way shuttle response than their yoked counterparts that received inescapable shock. In contrast, in Experiment 1b, rats trained to escape shock by performing a longer duration inactive response were more impaired on the subsequent escape task than their inescapably shocked counterparts. In Experiment 2, the results of Experiments 1a and 1b were replicated, and the inactive responses performed during pretreatment by both the escapable and inescapable shock groups were assessed and correlated with test stage 2-way shuttle escape performance. These activity data indicate that inactivity during pretreatment shock in both escapable and inescapable shock groups was a highly reliable predictor of subsequent 2-way shuttle performance, irrespective of the pretreatment shock contingency to which these Ss were exposed.

Multilevel modelling of aircraft noise on performance tests in schools around Heathrow Airport London.

STUDY OBJECTIVE: To examine the effects of chronic exposure to aircraft noise on children's school performance taking into account social class and school characteristics. DESIGN: This is a cross sectional study using the National Standardised Scores (SATs) in mathematics, science, and English (11 000 scores from children aged 11 years). The analyses used multilevel modelling to determine the effects of chronic aircraft noise exposure on childrens' school performance adjusting for demographic, socioeconomic and school factors in 123 primary schools around Heathrow Airport. Schools were assigned aircraft noise exposure level from the 1994 Civil Aviation Authority aircraft noise contour maps. SETTING: Primary schools. PARTICIPANTS: The sample were approximately 11 000 children in year 6 (approximately 11 years old) from 123 schools in the three boroughs surrounding Heathrow Airport. MAIN RESULTS: Chronic exposure to aircraft noise was significantly related to poorer reading and mathematics performance. After adjustment for the average socioeconomic status of the school intake (measured by percentage of pupils eligible for free school meals) these associations were no longer statistically significant. CONCLUSIONS: Chronic exposure to aircraft noise is associated with school performance in reading and mathematics in a dose-response function but this association is confounded by socioeconomic factors.

Total plasma cholesterol levels of rats are increased following only three sessions of tailshock.

Male Sprague-Dawley rats were maintained for three weeks on one of three different diets. Two of the diets were high-cholesterol, high-fat, while the third was standard laboratory chow. Animals from each group were then given either daily 2 hr sessions of tailshock for three days, or left in their home cage. Blood samples were taken from all subjects prior to stress, and again immediately after the third stress session. Sera were separated and analyzed for total plasma cholesterol. Results indicate that total plasma cholesterol was increased in the stressed animals maintained on standard lab chow. Stressed animals in the two high cholesterol diet groups showed no cholesterol increase relative to their respective dietary controls.

A controlled study of anxiety and morbid cognitions at initial screening for human immunodeficiency virus (HIV) in a cohort of people with haemophilia.

AIM: This study examines the relationship between anxiety, psychological state and Human Immunodeficiency Virus (HIV) stages as defined by the Centers for Disease Control at the time of initial screening for HIV in a cohort of people with haemophilia who were at risk of prior exposure to HIV transmission from blood products. METHOD: Psychological scores, immunological measures, and clinical data from case notes for 116 potentially HIV exposed people with haemophilia attending initial screening for HIV infection in 1984-1985, were used to examine the relationship between psychological variables, clinical state and their clinical classification under the Centres for Disease Control categorization. Psychometric test results were obtained for 63 HIV seronegative patients and 53 HIV seropositive patients. Planned comparisons, multiple and logistic regressions, were used to explain observed differences between seronegative and seropositive subjects. The potential confounders of sex, age, severity of haemophilia, haemophilia type and blood product usage were controlled. RESULTS: The major finding of this study was that higher levels of State Anxiety at the time of initial screening for HIV, were observed in those patients who lacked recognized symptoms of HIV infection and were seropositive, compared with seronegative subjects. The State Anxiety scores were predicted by HIV infection or alternatively CD4+ T-cell levels. CONCLUSION: The findings of this study suggest that HIV infection can produce psychological effects prior to any physical symptoms of infection being apparent.

The application of learning theory to driving confidence: the effect of age and the impact of random breath testing.

Despite the dangers, many drivers continue to take risks when driving. This paper outlines an explanation of this risk-taking behavior and the failure of numerous fear-arousing messages to change the manner in which many people drive. Being an occupant in a car and learning to drive may be seen as analogous to systemic desensitization and flooding procedures, in which fear is extinguished and/or a response inconsistent with fear is learned. Once this procedure is complete the fear response is unlikely to be reinstated by messages pointing out possible dangers on the road, because the situations in which the messages are received are usually inappropriate, and many believe that they are superior drivers and therefore not at risk. News presentation of the huge road toll and multiple fatality crashes may only confirm to many people that they are better than average drivers since so many other people have been killed or seriously injured, and they, the superior drivers, have not. A prediction of this account is that driving confidence will increase with increasing age, through the greater on-road fear-reducing experience and increased exposure to the road toll. This prediction was examined in surveys of 2,963 Australian drivers, conducted as part of the evaluation of random breath testing. Respondents were asked to rate their ability as drivers compared with average, and to rate their ability to drive under the influence of alcohol. The overconfidence observed in Canada, Sweden, New Zealand, and the United States was identified in Australian drivers. The predicted increase in confidence with increasing age was supported up to the age of 40 years, after which confidence changed little. Confidence in ability to drive after consuming alcohol increased steadily with age. Finally, it was predicted that the introduction of random breath testing and the associated media campaign partly about the effects of alcohol (which was successful in reducing the road toll) would decrease confidence in ability to drive under the influence of alcohol. Comparison of survey data before and after the introduction of random breath testing did not support this prediction.

Motor vehicle accidents, fatigue and optimism bias in taxi drivers.

Fatigue-related variables and their relationship with accident involvement were examined in a group of 42 Sydney metropolitan taxi drivers across a 2-year period. Advantages associated with the study of this group of road users include their important role in public transport, long hours spent on the road, job-related controls of exposure through shift patterns and the ability to verify accidents with company insurance records. Number and length of breaks, employment type, falling asleep at the wheel and a variety of other job-related and attitudinal variables were surveyed. Results provide basic data on fatigue-related aspects of the job of taxi driving. Driver time-on-the-road is often considerable: 67% of those surveyed drove at least 50 hours per week, yet time off in long shifts (up to 12 hours) was often short (as low as 3 minutes, with an average of 37 minutes). Self report of accidents proved reliable against insurance company records. A significant negative correlation between total average break time and accident rate was observed. Optimism bias was present for a variety of driving-related questions, including the ability to drive safely while fatigued.

Noise sensitivity as a factor influencing human reaction to noise.

Reaction (annoyance, dissatisfaction) to noise is itself an important health effect, as well as possibly contributing to other putative health effects of noise. Thus, factors such as noise sensitivity, which influence reaction, are of considerable importance. However, noise sensitivity is rarely clearly defined. This paper offers a formal definition of noise sensitivity, and reviews evidence relating to it. Noise sensitivity has been measured in various ways, but may be measured most directly by assessing reaction to many noise situations (other than those involving the noise source(s) which are the focus of the particular study). When noise sensitivity is measured in this way, factor analysis consistently reveals that noise sensitivity is not a unitary concept. Rather, two distinct factors appear: one related to loud noises (road traffic, lawn mower), and the other related to quieter noise situations which are nonetheless distracting (rustling papers at the movies, people talking while watching television). More research is needed to address the relationships between these factors, reaction and other health effects.

Effective Communication of Health Messages regarding Noise-Induced Health Effects.

Noise exposure in both residential and occupational settings produces a range of auditory and nonauditory health problems. Efforts of the relevant authorities to reduce these effects may be supplemented by the adoption of various self-protective behaviours by individuals. Unfortunately campaigns designed to encourage such self-protective behaviours are likely to meet with limited success. The present paper considers the shortcomings of such campaigns and offers prescriptions for improving them. Campaigns based on these prescriptions and on thorough research of the factors involved in health promotion generally, as well as those particular to each case, should significantly advance efforts toward individuals protecting themselves against the ill effects of noise exposure.