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1.
BMC Public Health ; 21(1): 1954, 2021 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-34711187

RESUMO

BACKGROUND: Motorcycles are one of the most commonly used transportation modes in low and middle-income countries. In India, motorized two-wheelers comprise 70% of the total vehicle population, and motorcycle users are considered the most vulnerable road users. It is essential to understand the risky riding behaviour and associated factors among the motorcyclists to develop evidence-based traffic safety programs targeting motorcycle riders. The purpose of the current study was two-fold. First, it aimed to determine the appropriate structure of a modified version of the MRBQ among young riders in Manipal, India. Second, it assessed to what extent MRBQ factors were associated with self-reported crash involvement and violations. METHODS: The motorcycle rider behaviour questionnaire (MRBQ) is a 43-item scale that assesses five aspects of risky motorcycle rider behaviour, i.e., violations, control errors, traffic errors, stunts, and protective equipment. The MRBQ, along with measures of socio-demographic variables and the number of motorcycle crashes, was filled out by 300 young motorcycle riders who were in the age group of 18-25 years and had been riding for at least the past three years (93% males, 92.3% students). RESULTS: Five factors emerged out of the MRBQ after an exploratory factor analysis: traffic errors, control errors, stunts, protective equipment, and violations. Cronbach's alpha for these factors ranged from .66 to .82. Reports of performing stunts and committing violations were positively associated with self-reported near-crash experiences over the past three months. Riders reporting stunts, violations and using a motorcycle of 125-200 cc reported having received more fines in the last three months. These findings were confirmed in both univariate and multivariate binary logistic regression models. CONCLUSION: The study assessed the factor structure of a modified version MRBQ and the extracted factors associations with self-reported crash involvement. The factor structure revealed in the current study is consistent with MRBQ factor structures found in other countries. However, the support for a relationship between MRBQ factors and self-reported crashes was less significant. The findings suggest that if replicated by future studies, local policymakers are advised to focus on the five MRBQ factors while planning future interventions to achieve a reduction in the number of road crashes among motorcyclists.


Assuntos
Acidentes de Trânsito , Motocicletas , Adolescente , Adulto , Feminino , Humanos , Índia/epidemiologia , Masculino , Assunção de Riscos , Inquéritos e Questionários , Adulto Jovem
2.
Ergonomics ; 63(4): 407-420, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31994986

RESUMO

Road geometric design standards provide various possibilities for merging freeways with a decreasing number of lanes. In this study, an alternative design (i.e. taper design) is investigated and compared with the standard design under three different heavy vehicle compositions to understand driving performance in relation to the flow of traffic. Taper design is not always the first choice in the road geometric design guidelines and the designer has to provide arguments for selecting this design. Taper design and its comparison with other alternatives are also not well explored in literature. In this study, a driving simulator was used to examine and compare the performance of these two designs under different heavy vehicle compositions. Qualitative results showed that the perceived safety was better for the standard design compared to the taper design. Mean speed, acceleration, standard deviation of acceleration/deceleration, and cumulative lane changes were chosen as behavioural parameters to compare these two designs using MANOVA and repeated measures ANOVA. Results revealed that drivers' discomfort in performing merging manoeuvres was greatest in case of a taper design and when the percentage of heavy vehicles was moderate (15%). Overall, the standard design was found to be more favourable. Practitioner summary: Driving behaviour at merging freeways with a decreasing number of lanes is underexplored. We analysed safety in driving behaviour considering heavy vehicles for taper and standard designs provided in Dutch guidelines using a driving simulator. The standard design was found to be safer and the presence of moderate heavy vehicles caused more disturbances in driving behaviour.


Assuntos
Condução de Veículo , Simulação por Computador , Planejamento Ambiental , Segurança , Adulto , Feminino , Humanos , Masculino
3.
Ergonomics ; 61(3): 429-443, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28689462

RESUMO

Intersection accidents result in a significant proportion of road fatalities, and attention allocation likely plays a role. Attention allocation may depend on (limited) working memory (WM) capacity. Driving is often combined with tasks increasing WM load, consequently impairing attention orienting. This study (n = 22) investigated WM load effects on event-related potentials (ERPs) related to attention orienting. A simulated driving environment allowed continuous lane-keeping measurement. Participants were asked to orient attention covertly towards the side indicated by an arrow, and to respond only to moving cars appearing on the attended side by pressing a button. WM load was manipulated using a concurrent memory task. ERPs showed typical attentional modulation (cue: contralateral negativity, LDAP; car: N1, P1, SN and P3) under low and high load conditions. With increased WM load, lane-keeping performance improved, while dual task performance degraded (memory task: increased error rate; orienting task: increased false alarms, smaller P3). Practitioner Summary: Intersection driver-support systems aim to improve traffic safety and flow. However, in-vehicle systems induce WM load, increasing the tendency to yield. Traffic flow reduces if drivers stop at inappropriate times, reducing the effectiveness of systems. Consequently, driver-support systems could include WM load measurement during driving in the development phase.


Assuntos
Atenção/fisiologia , Condução de Veículo , Potenciais Evocados , Memória de Curto Prazo , Carga de Trabalho , Adolescente , Adulto , Simulação por Computador , Feminino , Humanos , Masculino , Tempo de Reação , Análise e Desempenho de Tarefas , Adulto Jovem
4.
Ergonomics ; 60(5): 701-713, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-27376174

RESUMO

This study investigates the effect of two pavement markings (transverse rumble strips (TRS) and a backward pointing herringbone pattern (HP)) on speed and lateral control in and nearby curves. Two real-world curves with strong indications of a safety problem were replicated as realistic as possible in the simulator. Results show that both speed and lateral control differ between the curves. These behavioural differences are probably due to curve-related dissimilarities with respect to geometric alignment, cross-sectional design and speed limit. TRS and HP both influenced mean speed and mean acceleration/deceleration but not lateral control. TRS generated an earlier and more stable speed reduction than HP which induced significant speed reductions along the curve. The TRS gives drivers more time to generate the right expectations about the upcoming curve. When accidents occur primarily near the curve entry, TRS is recommended. The HP has the potential to reduce accidents at the curve end. Practitioner Summary: Two pavement markings (transversal rumble strips and HP) nearby dangerous curves were investigated in the driving simulator. TRS generated an earlier and more stable speed reduction than HP which induced speed reductions along the curve. The TRS gives drivers more time to generate right expectations about the upcoming curve.


Assuntos
Condução de Veículo , Planejamento Ambiental , Segurança , Aceleração , Acidentes de Trânsito/prevenção & controle , Adolescente , Adulto , Simulação por Computador , Desaceleração , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise e Desempenho de Tarefas , Adulto Jovem
5.
Neurol Sci ; 37(9): 1483-90, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27207680

RESUMO

In multiple sclerosis (MS), physical activity (PA) is most commonly measured as number of steps, while also walking intensity and walking activity duration are keys for a healthy lifestyle. The aim of this study was to investigate (1) the number of steps persons with MS (PwMS) take; (2) the number of steps they take at low and moderate intensity; and (3) their walking activity duration for 2, 3, 6, 10, 12 and 14 uninterrupted minutes; all related to the degree of disability. 64 PwMS participated, distinguished in a mild (n = 31) and moderate MS subgroup (n = 34) based on their ambulatory dysfunction (Disease Steps). Standardized clinical tests were performed, and step data from the StepWatch Activity Monitor were collected for seven consecutive days. The results showed that (1) step count in PwMS was lower than PA recommendations, and is negatively influenced by a higher disability degree. (2) No walking was registered during 77 % of the day. PwMS are making steps for 22 % at low and only 1 % at moderate intensity. (3) Both MS subgroups rarely walk for more than six uninterrupted minutes, especially not at moderate intensity. PwMS need to be encouraged to make steps at moderate intensity, and to make steps for longer periods of time (minimal ten uninterrupted minutes).


Assuntos
Exercício Físico/fisiologia , Transtornos dos Movimentos/etiologia , Esclerose Múltipla/complicações , Desempenho Psicomotor/fisiologia , Caminhada/fisiologia , Adulto , Idoso , Estudos Transversais , Avaliação da Deficiência , Pessoas com Deficiência , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença
6.
Int J Inj Contr Saf Promot ; 31(1): 61-71, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37726982

RESUMO

Speeding increases the likelihood and severity of road traffic crashes, but many riders do not consider speeding as a serious safety issue. By using belief-based variables derived from the Theory of Planned Behaviour (i.e. behavioural beliefs, normative beliefs, and control beliefs), this study investigated the socio-cognitive determinants of speeding intentions among Vietnamese adolescents operating motorized/electrified two-wheelers. 189 adolescent powered two-wheeled riders in Ho Chi Minh City participated in a cross-sectional survey. The results lend clear support to the Expectancy-Value approach since belief-based product factors (e.g. outcome beliefs x outcome evaluations) significantly and independently contributed to the prediction of speeding intentions. Speeding intentions were mostly influenced by behavioural beliefs, followed by normative beliefs and control beliefs, respectively. This study not only proves the Expectancy-Value approach as an appropriate framework for the investigation of speeding intentions but also supports authorities in the formulation and execution of more effective interventions for reducing speeding among adolescent powered two-wheeled riders in Vietnam. Instead of motivation-oriented methods, there is a need for strategies that stimulate the translation of good intentions into the desirable behaviour, and encourage adolescents not to relapse in case they are exposed to risk facilitating circumstances. Yet, besides focussing on person-specific dispositions towards speeding, policy makers are advised to adopt a more broadly encompassing systemic approach with inclusion of safe roads, safe vehicles, improved post-crash care, and shared stakeholder responsibilities.


Assuntos
Acidentes de Trânsito , Condução de Veículo , Humanos , Adolescente , Acidentes de Trânsito/prevenção & controle , Vietnã , Estudos Transversais , Cognição
7.
JMIR Mhealth Uhealth ; 12: e52192, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38557808

RESUMO

Background: Despite being the gold-standard method for objectively assessing sleep, polysomnography (PSG) faces several limitations as it is expensive, time-consuming, and labor-intensive; requires various equipment and technical expertise; and is impractical for long-term or in-home use. Consumer wrist-worn wearables are able to monitor sleep parameters and thus could be used as an alternative for PSG. Consequently, wearables gained immense popularity over the past few years, but their accuracy has been a major concern. Objective: A systematic review of the literature was conducted to appraise the performance of 3 recent-generation wearable devices (Fitbit Charge 4, Garmin Vivosmart 4, and WHOOP) in determining sleep parameters and sleep stages. Methods: Per the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) statement, a comprehensive search was conducted using the PubMed, Web of Science, Google Scholar, Scopus, and Embase databases. Eligible publications were those that (1) involved the validity of sleep data of any marketed model of the candidate wearables and (2) used PSG or an ambulatory electroencephalogram monitor as a reference sleep monitoring device. Exclusion criteria were as follows: (1) incorporated a sleep diary or survey method as a reference, (2) review paper, (3) children as participants, and (4) duplicate publication of the same data and findings. Results: The search yielded 504 candidate articles. After eliminating duplicates and applying the eligibility criteria, 8 articles were included. WHOOP showed the least disagreement relative to PSG and Sleep Profiler for total sleep time (-1.4 min), light sleep (-9.6 min), and deep sleep (-9.3 min) but showed the largest disagreement for rapid eye movement (REM) sleep (21.0 min). Fitbit Charge 4 and Garmin Vivosmart 4 both showed moderate accuracy in assessing sleep stages and total sleep time compared to PSG. Fitbit Charge 4 showed the least disagreement for REM sleep (4.0 min) relative to PSG. Additionally, Fitbit Charge 4 showed higher sensitivities to deep sleep (75%) and REM sleep (86.5%) compared to Garmin Vivosmart 4 and WHOOP. Conclusions: The findings of this systematic literature review indicate that the devices with higher relative agreement and sensitivities to multistate sleep (ie, Fitbit Charge 4 and WHOOP) seem appropriate for deriving suitable estimates of sleep parameters. However, analyses regarding the multistate categorization of sleep indicate that all devices can benefit from further improvement in the assessment of specific sleep stages. Although providers are continuously developing new versions and variants of wearables, the scientific research on these wearables remains considerably limited. This scarcity in literature not only reduces our ability to draw definitive conclusions but also highlights the need for more targeted research in this domain. Additionally, future research endeavors should strive for standardized protocols including larger sample sizes to enhance the comparability and power of the results across studies.


Assuntos
Sono , Dispositivos Eletrônicos Vestíveis , Criança , Humanos , Polissonografia , Reprodutibilidade dos Testes , Monitores de Aptidão Física
8.
Autism ; 27(5): 1219-1234, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36341960

RESUMO

LAY ABSTRACT: Transportation plays an essential role in daily life, allowing people to participate in the community and form social relationships. Many autistic people rely on public transportation to meet their mobility needs. However, research shows that it is not always easy for them to use it. The exact issues autistic individuals face when traveling with public transportation and how public transportation can be made more autism-friendly have yet to be researched. The current study allowed autistic individuals to express themselves regarding issues they face while traveling by public bus transportation, to raise awareness for making public transportation more autism-friendly. We interviewed 17 autistic individuals about their experiences riding the bus. Three main themes emerged from the results: creating predictability, limiting stimuli, and open and accessible communication. If transport companies take initiatives related to these themes, autistic people traveling by bus can have a more pleasant experience. Participants also described coping strategies for stressful or uncomfortable situations while using public bus transportation, such as using noise-cancelling headphones or digital applications for real-time route tracking, etc. These findings may lead to a more autism-friendly public transportation.


Assuntos
Transtorno do Espectro Autista , Transtorno Autístico , Humanos , Meios de Transporte , Emoções , Adaptação Psicológica
9.
J Safety Res ; 85: 348-360, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37330884

RESUMO

INTRODUCTION: In Vietnam, road traffic crashes are one of the leading causes of death and serious injury in adolescents, especially in the 15-19-year age group. Wrong lane riding (WLR) is seen as the most common risky behavior of adolescent two-wheeled riders. This study (a) tested the expectancy-value model held to underpin the key determinants of behavioral intention (i.e., attitude, subjective norm, perceived behavioral control) as proposed by the Theory of Planned Behavior, and (b) identified appropriate targets for road safety interventions. METHOD: A cluster random sample of 200 adolescent two-wheeled riders in Ho Chi Minh City participated in a cross-sectional study designed to measure the variables of interest (i.e., behavioral beliefs, normative beliefs, control beliefs, and intention towards wrong lane riding). RESULTS: The results of hierarchical multiple regression lend clear support for the expectancy-value theory as an approach to model the different belief components behind the key determinants of behavioral intention. CONCLUSION: Road safety interventions aimed at reducing WLR among Vietnamese adolescent two-wheeled riders would best target both the cognitive and the affective components of attitude, subjective norm, and perceived behavioral control. Interestingly, the sample investigated in this study is rather negatively predisposed toward WLR. PRACTICAL APPLICATIONS: It is recommended to further strengthen and stabilize these safety-oriented beliefs, and to develop the required implementation intentions to guarantee that the appropriate goal intentions in terms of WLR are translated into action. More research is needed to see whether the commission of WLR can also be explained in function of a reactive pathway, or is exclusively under volitional control.


Assuntos
Intenção , População do Sudeste Asiático , Humanos , Adolescente , Estudos Transversais , Vietnã , Atitude , Acidentes de Trânsito/prevenção & controle
10.
Accid Anal Prev ; 150: 105916, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33296840

RESUMO

Transition zones are a road section where posted speed drops from higher to lower limits. Due to the sudden changes in posted speed limits and road environment, drivers usually do not adapt to the posted speed limits and underestimate their traveling speed. Previous studies have highlighted that crash rates are usually higher in these sections. This study aims at improving the safety at transition zones by introducing perceptual measures that are tested using a driving simulator. The proposed measures are speed limit pavement markings with a gradual increase of brightness and/or size that were placed at transition zones in simulation scenarios replicating the real-world environment of the Doha Expressway in Qatar. These innovative measures aim to produce the impression of increased speed that could stimulate drivers to better adapt speed limits. The driving behavior of 81 drivers possessing a valid Qatari driving license was recorded with a driving simulator interfaced with STISIM Drive® 3. Results showed that pavement markings combining size and brightness manipulations were the most effective treatment, keeping drivers' traveling speed significantly below the traveling speed recorded in the untreated control condition. In this regard, the maximum mean speed reductions of 5.3 km/h and 4.6 km/h were observed for this treatment at the first transition (120 to 100 km/h) and second transition (100 to 80 km/h) zones, respectively. Regarding the variations in drivers' lateral position, the results showed that the proposed pavement markings did not negatively influence drivers' lateral control on the road as the maximum observed standard deviation of lateral position was around 0.065 m. This study shows that the proposed pavement markings are recommended for improving the speed adaptation of drivers in the transition zones.


Assuntos
Acidentes de Trânsito , Condução de Veículo , Acidentes de Trânsito/prevenção & controle , Simulação por Computador , Planejamento Ambiental , Humanos , Catar , Segurança , Visão Ocular
11.
Accid Anal Prev ; 138: 105484, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32105839

RESUMO

Inter-national benchmarking of road safety, with the purpose of achieving continuous improvement by learning lessons from existing best practices, has currently been widely encouraged by most countries as an emerging management tool to improve the level of road safety. However, performing a successful road safety benchmarking practice is by no means easy. Challenges exist from ascertaining the benchmarking framework at the very beginning to making final policy decisions. In this study, based on the identification of leading road safety risk factors, a comprehensive set of hierarchically structured safety performance indicators was developed, some necessary data processing procedures were conducted, and the use of data envelopment analysis (DEA) for composite indicator (CI) construction was elaborated. An interval multiple layer DEA-based CI model was proposed to take both the hierarchical structure of the indicators and the data uncertainty into account, and was used to benchmark road safety performance for a set of European countries. Based on the model output, best-performing and underperforming countries were distinguished and all the countries were further ranked by computing their cross-index score. Moreover, by taking the characteristics of each country in the data set into account, country-specific benchmarks for those underperforming countries were identified, and useful insight in the areas of underperformance in each country was gained. Meanwhile, by summarizing the risk aspects that need urgent policy action for all these countries, some specific road safety enhancing recommendations for this region as a whole were formulated.


Assuntos
Benchmarking/métodos , Ambiente Construído/normas , Gestão da Segurança/métodos , Acidentes de Trânsito/prevenção & controle , Europa (Continente) , Humanos
12.
Sci Total Environ ; 407(12): 3814-22, 2009 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-19344931

RESUMO

The potential advantages of using activity-based transport models for air quality purposes have been recognized for a long time but models that have been developed along these lines are still scarce. In this paper we demonstrate that an activity-based model provides useful information for predicting hourly ambient pollutant concentrations. For this purpose, the traffic emissions obtained in a previous application of the activity-based model ALBATROSS were used as input for the AURORA air quality model to predict hourly concentrations of NO(2), PM(10) and O(3) in the Netherlands. Predicted concentrations were compared with measured concentrations at 37 monitoring stations from the Dutch air quality monitoring network. A statistical analysis was performed to evaluate model performance for different pollutants, locations and time periods. Results confirm that modelled and measured concentrations present the same geographical and temporal variation. The overall index of agreement for the prediction of hourly pollutant concentrations amounted to 0.64, 0.75 and 0.57 for NO(2), O(3) and PM(10) respectively. Concerning the predictions for NO2, a major traffic pollutant, a more thorough analysis revealed that the ALBATROSS-AURORA model chain yielded better predictions near traffic locations than near background stations. Further, the model performed better in urban areas, on weekdays and during the day, consistent with the emission results obtained in a previous study. The results in this paper demonstrate the ability of the activity-based model to predict the contribution of traffic sources to local air pollution with sufficient accuracy and confirms the usefulness of activity-based transport models for air quality purposes. The fact that the ALBATROSS-AURORA chain provides reliable pollutant concentrations on hourly basis for the whole Netherlands instead of using only daily averages near traffic stations is a plus for future exposure studies aiming at more realistic exposure analyses and health impact assessments.


Assuntos
Poluição do Ar/análise , Modelos Estatísticos , Meios de Transporte , Emissões de Veículos/análise , Poluição do Ar/estatística & dados numéricos , Comportamento , Reprodutibilidade dos Testes
13.
Accid Anal Prev ; 123: 211-221, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30529992

RESUMO

Behavioural observation studies in road safety research collect naturalistic data of road users that are not informed (beforehand) of their participation in a research project. It enables the observation of behavioural and situational processes that contribute to unsafe traffic events, while possible behavioural adaptations due to the road users' recognition of being observed are minimized. The literature in this field is vast and diverse, with studies dating back to the 1930s. The aim of this paper is to summarize the research efforts in the domain of road user behavioural observation research to examine trends and developments of this type of research, using a scoping review. After the definition of certain selection criteria, 600 journal articles found in three major online databases were retrieved and included in this review. The number of publications regarding road user behavioural observation studies has increased rapidly during recent years, indicating the importance of behavioural observation studies to study traffic safety. Most studies collected data on car drivers (81%), while vulnerable road users have been observed in 32% of all studies, with pedestrians and (motor)cyclists as the most common road user types. The results showed that the main goal of behavioural observation is to monitor (51%), followed by the evaluation of a specific safety improving measure (38%) and the development of behavioural models (10%). Most topics relate to traffic events where interactions with other road users are necessary, indicating that the examination of behavioural processes underlying single-vehicle crashes has received little attention. The ongoing developments of automated video analysis software tools can be the next methodological step forward in video-based behavioural observation studies, since it enables a more objective data collection and data analysis process.


Assuntos
Condução de Veículo/psicologia , Técnicas de Observação do Comportamento , Acidentes de Trânsito/estatística & dados numéricos , Adaptação Psicológica , Coleta de Dados/métodos , Bases de Dados Factuais , Humanos , Pedestres/psicologia , Segurança
14.
Accid Anal Prev ; 40(2): 518-26, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18329402

RESUMO

A before-and-after study was carried out of injury accidents involving bicyclists on 91 roundabouts in Flanders-Belgium. The study design accounted for the effects of general safety trends and regression-to-the-mean, but could not take into account the possibility of specific changes in traffic volume at roundabouts. The conversion of intersections into roundabouts produces a significant 27% increase in the number of injury accidents involving bicyclists on or nearby the roundabouts. The increase is even higher for accidents involving fatal or serious injuries (41-46%). Compared to the proven favourable effects of roundabouts on safety in general, this result is unexpectedly poor. However, the effects of roundabouts on bicycle accidents differ depending on whether these roundabouts are built inside or outside built-up areas. When inside built-up areas, the construction of roundabouts increased the number of injury accidents involving bicyclists by 48%. For accidents causing fatal or serious injuries inside built-up areas, an average increase of 77% was found. However, outside built-up areas the zero-hypothesis of 'no safety effect for bicyclists' cannot be rejected (best estimate: +1% accidents, not significant). Roundabouts that replace traffic signals perform worse when compared to roundabouts at other types of intersections.


Assuntos
Acidentes de Trânsito/prevenção & controle , Automóveis , Ciclismo , Planejamento Ambiental , Segurança , Humanos , Modelos Estatísticos , Medição de Risco , Fatores de Risco
15.
Accid Anal Prev ; 40(3): 1180-90, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18460387

RESUMO

In previous research, significant effects of weather conditions on car crashes have been found. However, most studies use monthly or yearly data and only few studies are available analyzing the impact of weather conditions on daily car crash counts. Furthermore, the studies that are available on a daily level do not explicitly model the data in a time-series context, hereby ignoring the temporal serial correlation that may be present in the data. In this paper, we introduce an integer autoregressive model for modelling count data with time interdependencies. The model is applied to daily car crash data, metereological data and traffic exposure data from the Netherlands aiming at examining the risk impact of weather conditions on the observed counts. The results show that several assumptions related to the effect of weather conditions on crash counts are found to be significant in the data and that if serial temporal correlation is not accounted for in the model, this may produce biased results.


Assuntos
Prevenção de Acidentes/métodos , Acidentes de Trânsito/estatística & dados numéricos , Clima , Humanos , Modelos Estatísticos , Modelos Teóricos , Distribuição de Poisson , Regressão Psicológica , Medição de Risco , Fatores de Risco , Fatores de Tempo , Estudos de Tempo e Movimento
16.
Accid Anal Prev ; 40(4): 1257-66, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18606254

RESUMO

Traffic accident data are often heterogeneous, which can cause certain relationships to remain hidden. Therefore, traffic accident analysis is often performed on a small subset of traffic accidents or several models are built for various traffic accident types. In this paper, we examine the effectiveness of a clustering technique, i.e. latent class clustering, for identifying homogenous traffic accident types. Firstly, a heterogeneous traffic accident data set is segmented into seven clusters, which are translated into seven traffic accident types. Secondly, injury analysis is performed for each cluster. The results of these cluster-based analyses are compared with the results of a full-data analysis. This shows that applying latent class clustering as a preliminary analysis can reveal hidden relationships and can help the domain expert or traffic safety researcher to segment traffic accidents.


Assuntos
Acidentes de Trânsito/estatística & dados numéricos , Análise por Conglomerados , Ferimentos e Lesões/epidemiologia , Acidentes de Trânsito/classificação , Adolescente , Adulto , Idoso , Algoritmos , Bélgica/epidemiologia , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Medição de Risco
17.
Accid Anal Prev ; 40(4): 1337-44, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18606264

RESUMO

In this paper we focus on an essential step in the construction process of a composite road safety performance indicator: the assignment of weights to the individual indicators. In the composite indicator literature, this subject has been discussed for a long time, and no agreement has been reached so far. The aim of this research is to provide insights in the most important weighting methods: factor analysis, analytic hierarchy process, budget allocation, data envelopment analysis and equal weighting. We will give the essential theoretical considerations, apply the methods on road safety data from various countries and discuss their advantages and disadvantages. This will facilitate the selection of a justifiable method. It is shown that the position of a country in the ranking is influenced by the method used. The weighting methods agree more for countries with a relatively bad road safety performance. Of the five techniques, the weights based on data envelopment analysis resulted in the highest correlation with the road safety ranking of 21 European countries based on the number of traffic fatalities per million inhabitants. This method is valuable for the development of a road safety index.


Assuntos
Acidentes de Trânsito/prevenção & controle , Acidentes de Trânsito/estatística & dados numéricos , Indicadores de Qualidade em Assistência à Saúde , Segurança/estatística & dados numéricos , Ferimentos e Lesões/epidemiologia , Ferimentos e Lesões/prevenção & controle , Algoritmos , Europa (Continente)/epidemiologia , Análise Fatorial , Humanos , Reprodutibilidade dos Testes
18.
Accid Anal Prev ; 119: 114-121, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30016751

RESUMO

The current safety concerns with buses/minibuses (public transport) in both developed and developing countries have warranted a renewed interest in bus/minibus safety research. Prior to this, there was a paucity of research in this domain especially in developed countries where the safety associated with buses was deemed adequate. In this study, we examined the factors that influence bus/minibus accident severity in Ghana using bus/minibus accident data from 2011-2015. We estimated the severity of bus/minibus accidents by fitting generalised ordered logit models. Our findings revealed that weekends, the absence of road median, night-time conditions, bad road terrain (curved, wet and rough roads), hit-pedestrian collisions, and drunk driving are associated with more severe bus/minibus accident outcomes. Conversely, minibuses, the absence of road shoulder, accidents in intersections, the presence of traffic control and collision types (except hit-pedestrian) are associated with less severe bus/minibus accidents.


Assuntos
Acidentes de Trânsito/estatística & dados numéricos , Veículos Automotores/estatística & dados numéricos , Segurança , Países em Desenvolvimento , Dirigir sob a Influência/estatística & dados numéricos , Planejamento Ambiental , Gana , Humanos , Escala de Gravidade do Ferimento , Modelos Logísticos , Pedestres/estatística & dados numéricos , Fatores de Risco
19.
Peptides ; 27(12): 3137-53, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17049409

RESUMO

Bioactive (neuro)peptides play critical roles in regulating most biological processes in animals. Peptides belonging to the same family are characterized by a typical sequence pattern that is conserved among the family's peptide members. Such a conserved pattern or motif usually corresponds to the functionally important part of the biologically active peptide. In this paper, all known bioactive (neuro)peptides annotated in Swiss-Prot and TrEMBL protein databases are collected, and the pattern searching program Pratt is used to search these unaligned peptide sequences for conserved patterns. The obtained patterns are then refined by combining the information on amino acids at important functional sites collected from the literature. All the identified patterns are further tested by scanning them against Swiss-Prot and TrEMBL protein databases. The diagnostic power of each pattern is validated by the fact that any annotated protein from Swiss-Prot and TrEMBL that contains one of the established patterns, is indeed a known (neuro)peptide precursor. We discovered 155 novel peptide patterns in addition to the 56 established ones in the PROSITE database. All the patterns cover 110 peptide families. Fifty-five of these families are not characterized by the PROSITE signatures, and 12 are also not identified by other existing motif databases, such as Pfam and SMART. Using the newly identified peptide signatures as a search tool, we predicted 95 hypothetical proteins as putative peptide precursors.


Assuntos
Sequência Conservada , Peptídeos/química , Motivos de Aminoácidos , Sequência de Aminoácidos , Simulação por Computador , Substâncias de Crescimento/química , Substâncias de Crescimento/fisiologia , Modelos Biológicos , Peptídeos Opioides/química , Peptídeos Opioides/fisiologia , Peptídeos/genética , Peptídeos/fisiologia , Toxinas Biológicas/química , Toxinas Biológicas/fisiologia
20.
J Safety Res ; 37(1): 83-91, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16513136

RESUMO

INTRODUCTION: In this paper a sensitivity analysis is performed to investigate how big the impact would be on the current ranking of crash locations in Flanders (Belgium) when only taking into account the most serious injury per crash instead of all the injured occupants. RESULTS: Results show that this would lead to a different selection of 23.8% of the 800 sites that are currently considered as dangerous. CONCLUSIONS: Considering this impact quantity, the researchers want to sensitize government that giving weight to the severity of the crash can correct for the bias that occurs when the number of occupants of the vehicles are subject to coincidence. Additionally, probability plots are generated to provide policy makers with a scientific instrument with intuitive appeal to select dangerous road locations on a statistically sound basis. Impact on industry Considering the impact quantity of giving weight to the severity of the crash instead of to all the injured occupants of the vehicle on the ranking of crash sites, the authors want to sensitize government to carefully choose the criteria for ranking and selecting crash locations in order to achieve an enduring and successful traffic safety policy. Indeed, giving weight to the severity of the crash can correct for the bias that occurs when the number of occupants of the vehicles are subject to coincidence. However, it is up to the government to decide which priorities should be stressed in the traffic safety policy. Then, the appropriate weighting value combination can be chosen to rank and select the most dangerous crash locations. Additionally, the probability plots proposed in this paper can provide policy makers with a scientific instrument with intuitive appeal to select dangerous road locations on a statistically sound basis. Note that, in practice, one should not only rank the crash locations based on the benefits that can be achieved from tackling these locations. Future research is also needed to incorporate the costs of infrastructure measures and other actions that these crash sites require in order to enhance the safety on these locations. By balancing these costs and benefits against each other, the crash locations can then be ranked according to the order in which they should be prioritized.


Assuntos
Acidentes de Trânsito/classificação , Acidentes de Trânsito/estatística & dados numéricos , Teorema de Bayes , Bélgica , Humanos
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