Project

Updated estimates of the relationship between speed and road safety at the aggregate and individual levels

Recent studies of the relationship between the speed of traffic and road safety, stated as the number of fatalities and the number of injury accidents, are reviewed and their results synthesised by means of meta-analysis. All studies were based on data

Traffic volume and crashes and how crash and road characteristics affect their relationship – A meta-analysis

The present study has investigated the relationship between traffic volume and crash numbers by means of meta-analysis, based on 521 crash prediction models from 118 studies. The weighted pooled volume coefficient for all crashes and all levels of crash

Risk of road accident associated with the use of drugs: A systematic review and meta-analysis of evidence from epidemiological studies

This paper is a corrigendum to a previously published paper where errors were detected. The errors have been corrected in this paper. The paper is otherwise identical to the previously published paper. A systematic review and meta-analysis of studies that

The effects of cannabis intoxication on motor vehicle collision revisited and revised

Aims: To determine whether and to what extent acute cannabis intoxication increases motor vehicle crash risk.

Design: Study 1 replicates two published meta-analyses, correcting for methodological shortcomings. Study 2 is an updated meta-analysis using

A synthesis of studies of access point density as a risk factor for road accidents

Studies of the relationship between access point density (number of access points, or driveways, per kilometre of road) and accident frequency or rate (number of accidents per unit of exposure) have consistently found that accident rate increases when

Does a tow-bar increase the risk of neck injury in rear-end collisions?

Does a tow-bar increase the risk of neck injury in the struck car in a rear-end collision? The rear part of a modern car has collision zones that are rendered nonoperational when the car is equipped with a tow-bar. Past crash tests have shown that a car's

Exploring the safety in numbers effect for vulnerable road users on a macroscopic scale

A “Safety in Numbers” effect for a certain group of road users is present if the number of crashes increases at a lower rate than the number of road users. The existence of this effect has been invoked to justify investments in multimodal transportation

Bicycle helmets – To wear or not to wear? A meta-analyses of the effects of bicycle helmets on injuries

A meta-analysis has been conducted of the effects of bicycle helmets on serious head injury and other injuries among crash involved cyclists. 179 effect estimates from 55 studies from 1989–2017 are included in the meta-analysis. The use of bicycle helmets

Recommend or mandate? A systematic review and meta-analysis of the effects of mandatory bicycle helmet legislation

If all cyclistswere wearing helmets, significant numbers of head injuries might theoretically be prevented. Mandatory bicycle helmet legislation increases helmet use but is a controversial measure. Results from 21 studies of the effects of mandatory

Interpreting interaction effects in estimates of the risk of traffic injury associated with the use of illicit drugs

Interactions characterise the relationship between use of amphetamines, cannabis and opiates as a driver and the risk of traffic injury associated with the use of these drugs. Inverse risk curves have been found for these drugs, meaning that the higher the

Vehicle registration year, age, and weight – Untangling the effects on crash risk

The aim of the present study was to investigate the effects of passenger cars’ first year of registration, weight, and age on the number of killed or seriously injured (KSI) car drivers, pedestrians, and cyclists. Poisson regression models were developed

The more (sharp) curves, the lower the risk

The risk of accident in horizontal curves is a complex function of at least the following characteristics of the curve: the radius of the curve; the length of the curve (and the resultant deflection angle); the presence of a spiral transition curve; the

Exploring factors influencing the strength of the safety-in-numbers effect

Several studies have found a so-called safety-in-numbers effect for vulnerable road users. This means that when the number of pedestrians or cyclists increases, the number of accidents involving these road users and motor vehicles increases less than in

Road safety effects of roundabouts: A meta-analysis

This paper presents a meta-analysis of the road safety effects of converting junctions to roundabouts. 44 studies containing a total of 154 estimates of effect were included. Based on a meta-regression analysis, converting junctions to roundabouts is

Safety-in-numbers: A systematic review and meta-analysis of evidence

This paper presents a systematic review and meta-analysis of studies that have estimated the relationship between the number of accidents involving motor vehicles and cyclists or pedestrians and the volume of motor vehicles, cyclists and pedestrians. A key

Association between increase in fixed penalties and road safety outcomes: A meta-analysis.

Studies that have evaluated the association between increases in traffic fine amounts (fixed penalties) and changes in compliance with road traffic law or the number of accidents are synthesised by means of meta-analysis. The studies were few and different

Does the influence of risk factors on accident occurrence change over time?

A large number of studies have been made to assess the relationship between risk factors and accident occurrence. A risk factor is any factor that makes an accident more likely to occur. Very many risk factors have been identified, for example, being under

Safety-in-numbers: Estimates based on a sample of pedestrian crossings in Norway

Safety-in-numbers denotes the tendency for the risk of accident for each road user to decline as the number of road users increases. Safety-in-numbers implies that a doubling of the number of road users will be associated with less than a doubling of the

A theoretical perspective on road safety communication campaigns

This paper proposes a theoretical perspective on road safety communication campaigns, which may help in identifying the conditions under which such campaigns can be effective. The paper proposes that, from a theoretical point of view, it is reasonable to

How would increasing seat belt use affect the number of killed or seriously injured light vehicle occupants?

The expected effects of increasing seat belt use on the number of killed or seriously injured (KSI) light vehicle occupants have been estimated for three scenarios of increased seat belt use in Norway, taking into account current seat belt use, the effects

Speed cameras, section control, and kangaroo jumps–a meta-analysis.

A meta-analysis was conducted of the effects of speed cameras and section control (point-to-point speed cameras) on crashes. 63 effect estimates from 15 speed camera studies and five effect estimates from four section control studies were included in the

Graduated Driver Licensing (GDL): Searching for the Best Composition of Components

Young drivers 16-19 years have a relative accident risk of 9-10 compared to drivers aged 55-64 years. Education and training of young drivers, which could reduce the death toll, have been an issue for many decades, but without much success regarding the

Still red light for red light cameras? An update

The present study has replicated the results from a previous meta-analysis by Erke (2009) [Erke, A., 2009. Red light for red-light cameras? A meta-analysis of the effects of red-light cameras on crashes. Accident Analysis & Prevention 41 (5), 897–905.]