77,214 research outputs found
Application of non-HDL cholesterol for population-based cardiovascular risk stratification: results from the Multinational Cardiovascular Risk Consortium.
BACKGROUND: The relevance of blood lipid concentrations to long-term incidence of cardiovascular disease and the relevance of lipid-lowering therapy for cardiovascular disease outcomes is unclear. We investigated the cardiovascular disease risk associated with the full spectrum of bloodstream non-HDL cholesterol concentrations. We also created an easy-to-use tool to estimate the long-term probabilities for a cardiovascular disease event associated with non-HDL cholesterol and modelled its risk reduction by lipid-lowering treatment. METHODS: In this risk-evaluation and risk-modelling study, we used Multinational Cardiovascular Risk Consortium data from 19 countries across Europe, Australia, and North America. Individuals without prevalent cardiovascular disease at baseline and with robust available data on cardiovascular disease outcomes were included. The primary composite endpoint of atherosclerotic cardiovascular disease was defined as the occurrence of the coronary heart disease event or ischaemic stroke. Sex-specific multivariable analyses were computed using non-HDL cholesterol categories according to the European guideline thresholds, adjusted for age, sex, cohort, and classical modifiable cardiovascular risk factors. In a derivation and validation design, we created a tool to estimate the probabilities of a cardiovascular disease event by the age of 75 years, dependent on age, sex, and risk factors, and the associated modelled risk reduction, assuming a 50% reduction of non-HDL cholesterol. FINDINGS: Of the 524 444 individuals in the 44 cohorts in the Consortium database, we identified 398 846 individuals belonging to 38 cohorts (184 055 [48·7%] women; median age 51·0 years [IQR 40·7-59·7]). 199 415 individuals were included in the derivation cohort (91 786 [48·4%] women) and 199 431 (92 269 [49·1%] women) in the validation cohort. During a maximum follow-up of 43·6 years (median 13·5 years, IQR 7·0-20·1), 54 542 cardiovascular endpoints occurred. Incidence curve analyses showed progressively higher 30-year cardiovascular disease event-rates for increasing non-HDL cholesterol categories (from 7·7% for non-HDL cholesterol <2·6 mmol/L to 33·7% for ≥5·7 mmol/L in women and from 12·8% to 43·6% in men; p<0·0001). Multivariable adjusted Cox models with non-HDL cholesterol lower than 2·6 mmol/L as reference showed an increase in the association between non-HDL cholesterol concentration and cardiovascular disease for both sexes (from hazard ratio 1·1, 95% CI 1·0-1·3 for non-HDL cholesterol 2·6 to <3·7 mmol/L to 1·9, 1·6-2·2 for ≥5·7 mmol/L in women and from 1·1, 1·0-1·3 to 2·3, 2·0-2·5 in men). The derived tool allowed the estimation of cardiovascular disease event probabilities specific for non-HDL cholesterol with high comparability between the derivation and validation cohorts as reflected by smooth calibration curves analyses and a root mean square error lower than 1% for the estimated probabilities of cardiovascular disease. A 50% reduction of non-HDL cholesterol concentrations was associated with reduced risk of a cardiovascular disease event by the age of 75 years, and this risk reduction was greater the earlier cholesterol concentrations were reduced. INTERPRETATION: Non-HDL cholesterol concentrations in blood are strongly associated with long-term risk of atherosclerotic cardiovascular disease. We provide a simple tool for individual long-term risk assessment and the potential benefit of early lipid-lowering intervention. These data could be useful for physician-patient communication about primary prevention strategies. FUNDING: EU Framework Programme, UK Medical Research Council, and German Centre for Cardiovascular Research
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Construction safety and digital design: a review
As digital technologies become widely used in designing buildings and infrastructure, questions arise about
their impacts on construction safety. This review explores relationships between construction safety and
digital design practices with the aim of fostering and directing further research. It surveys state-of-the-art
research on databases, virtual reality, geographic information systems, 4D CAD, building information
modeling and sensing technologies, finding various digital tools for addressing safety issues in the
construction phase, but few tools to support design for construction safety. It also considers a literature on
safety critical, digital and design practices that raises a general concern about ‘mindlessness’ in the use of
technologies, and has implications for the emerging research agenda around construction safety and digital
design. Bringing these strands of literature together suggests new kinds of interventions, such as the
development of tools and processes for using digital models to promote mindfulness through multi-party
collaboration on safet
Air Traffic Management Safety Challenges
The primary goal of the Air Traffic Management (ATM) system is to control accident risk. ATM
safety has improved over the decades for many reasons, from better equipment to additional
safety defences. But ATM safety targets, improving on current performance, are now extremely
demanding. Safety analysts and aviation decision-makers have to make safety assessments
based on statistically incomplete evidence. If future risks cannot be estimated with precision,
then how is safety to be assured with traffic growth and operational/technical changes? What
are the design implications for the USA’s ‘Next Generation Air Transportation System’
(NextGen) and Europe’s Single European Sky ATM Research Programme (SESAR)? ATM
accident precursors arise from (eg) pilot/controller workload, miscommunication, and lack of upto-
date information. Can these accident precursors confidently be ‘designed out’ by (eg) better
system knowledge across ATM participants, automatic safety checks, and machine rather than
voice communication? Future potentially hazardous situations could be as ‘messy’ in system
terms as the Überlingen mid-air collision. Are ATM safety regulation policies fit for purpose: is it
more and more difficult to innovate, to introduce new technologies and novel operational
concepts? Must regulators be more active, eg more inspections and monitoring of real
operational and organisational practices
Review of current practices in recording road traffic incident data: with specific reference to spatial analysis and road policing policy
Road safety involves three major components: the road system, the human factor and the vehicle element.
These three elements are inter-linked through geo-referenced traffic events and provide the basis for road
safety analyses and attempts to reduce the number of road traffic incidents and improve road safety.
Although numbers of deaths and serious injuries are back to approximately the 1950s levels when there
were many fewer vehicles on the road, there are still over 100 fatalities or serious injuries every day, and
this is a considerable waste of human capital. It is widely acknowledged that the location perspective is the
most suitable methodology by which to analyse different traffic events, where by in this paper, I will
concentrating on the relationship between road traffic incidents and traffic policing. Other methods include
studying road and vehicle engineering and these will be discussed later. It is worth noting here that there is
some division within the literature concerning the definitions of ‘accident’ and ‘incident’. In this paper I
will use ‘incident’ because it is important to acknowledge a vast majority of ‘road accidents’ are in fact
crimes. However I will use the term ‘accident’ where it is referred to in the literature or relevant reports. It
is important to mention here that a road traffic accident can be defined as ‘the product of an unwelcome
interaction between two or more moving objects, or a fixed and moving object’ (Whitelegg 1986). Road
safety and road incident reduction relates to many other fields of activity including education, driver
training, publicity campaigns, police enforcement, road traffic policing, the court system, the National
Health Service and Vehicle engineering.
Although the subject of using GIS to analyse road traffic incidents has not received much academic
attention, it lies in the field of crime mapping which is becoming increasingly important. It is clear that
studies have been attempted to analyse road traffic incidents using GIS are increasingly sophisticated in
terms of hypotheses and statistical technique (for example see Austin, Tight and Kirby 1997). However it is
also clear that there is considerable blurring of boundaries and the analysis of road accidents sits
uncomfortably in crime mapping. This is due to four main reasons:
- Road traffic incidents are associated with road engineering, which is concerned with generic
solutions while road traffic analysis is about sensitivity to particular contexts.
- Not all road traffic incidents are crimes
- It is not just the police who have an interest in reducing road traffic incidents, other partners
include local authorities, hospitals and vehicle manufacturers
- The management of road traffic incidents is not just confined to the police
GIS has been used for over thirty years however it has only been recently been used in the field of
transportation. The field of transportation has come to embrace Geographical Information Systems as a keytechnology to support its research and operational need. The acronym GIS-T is often employed to refer to
the application and adaptation of GIS to research, planning and management in transportation. GIS-T
covers a broad arena of disciplines of which road traffic incident detection is just one theme. Others include
in vehicle navigation systems.
Initially it was only used to ask simple accident enquiries such as depicting the relative incidence of
accidents in wet weather or when there is no street lighting, or to flag high absolute or relative incidences
of accidents (see Anderson 2002). Recently however there has been increased acknowledgement that there
is a requirement to go beyond these simple questions and to extend the analyses. It has been widely claimed
by academics and the police alike that knowing where road accidents occur must lead to better road
policing, in order to ensure that road policing becomes better integrated with other policing activities. This
paper will be used to explore issues surrounding the analysis of road traffic accidents and how GIS
analysts, police and policy makers can achieve a better understanding of road traffic incidents and how to
reduce them.
For the purpose of this study I will be trying to achieve a broader overview of the aspects concerning road
accident analysis with a strong emphasis on data quality and accuracy with concern to GIS analysis. Data
quality and accuracy are seen as playing a pivotal role in the road traffic management agenda because they assist the police and Local Authorities as to the specific location whereby management can be undertaken.
Part one will consider the introduction to road incidents and their relationship with geography and spatial
analysis and how this were initially applied to locating ‘hotspots’ and the more recent theory of ‘accident
migration’. Part two will address current data issues of the UK collection procedure. This section will pay
particular reference to geo-referencing and the implication of data quality on the procedure of analysing
road incidents using GIS. Part three addresses issues surrounding the spatial analysis of road traffic
incidents, including some techniques such as spatial autocorrelation, time-space geography and the
modifiable area unit problem. Finally part four looks at the role of effective road traffic policing and how
this can be achieved due to better understanding of the theory and issues arising from analysing road traffic
incidents. It will also look at the diffusion and use of GIS within the police and local authorities
A Method for the Study of Human Factors in Aircraft Operations
A method for the study of human factors in the aviation environment is described. A conceptual framework is provided within which pilot and other human errors in aircraft operations may be studied with the intent of finding out how, and why, they occurred. An information processing model of human behavior serves as the basis for the acquisition and interpretation of information relating to occurrences which involve human error. A systematic method of collecting such data is presented and discussed. The classification of the data is outlined
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Learning From Complexity: Effects Of Prior Accidents And Incidents On Airlines' Learning
Using data on accidents and incidents experienced by U.S. commercial airlines from 1983 to 1997, we investigated variation in firm learning by examining whether firms learn more from errors with heterogeneous or homogeneous causes. We measured learning by a reduction in airline accident and incident rates, while controlling for other factors related to accidents and incidents. Our results show that heterogeneity is generally better for learning, as prior heterogeneity in the causes of errors decreases subsequent accident rates, producing a deeper, broader search for causality than simple explanations like >blame the pilot.> The benefits of heterogeneity, however, apply mainly to specialist airlines. Generalist airlines learn, instead, from outside factors such as the experience of others and general improvements in technology. These results suggest a theory of learning across organizational forms: complex forms benefit from simple information, and simple forms benefit from complex information. The implications of our study for learning theories and work on organizational errors are discussed.Business Administratio
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