Bicycle helmet effectiveness is not overstated

Peer reviewe

Bicycle helmet law does not deter cyclists in Finland

Bicycle helmet legislation (BHL) in Finland went into effect in January 2003 and applies to cyclists of all ages. There are no mechanisms to fine cyclists riding without a helmet; however, helmet wearing rates are 64% in Helsinki and 42% across Finland. Our aim was to discuss possible effects of BHL on cycling in Finland. We used data from the 1998/1999, 2004/2005 and 2010/2011 Finnish National Travel Surveys. Data across three surveys suggest cycling has declined from before to after BHL. In a 2004/2005 survey, however, only 0.063% (95% CI: 0.02-0.10%) of responders identified helmet use as their most important obstacle to cycling. It is unlikely BHL is a causal factor in the downward trend in Finnish cycling. Lack of cycling infrastructure and concerns for safety are much more common reasons given. (C) 2018 Elsevier Ltd. All rights reserved.Peer reviewe

The interaction between cytosine methylation and processes of DNA replication and repair shape the mutational landscape of cancer genomes

© The Author(s) 2017. Methylated cytosines (5mCs) are frequently mutated in the genome. However, no studies have yet comprehensively analysed mutation-methylation associations across cancer types. Here we analyse 916 cancer genomes, together with tissue type-specific methylation and replication timing data. We describe a strong mutation-methylation association across colorectal cancer subtypes, most interestingly in samples with microsatellite instability (MSI) or Polymerase epsilon (POLE) exonuclease domain mutations. By analysing genomic regions with differential mismatch repair (MMR) efficiency, we suggest a possible role for MMR in the correction of 5mC deamination events, potentially accounting for the high rate of 5mC mutation accumulation in MSI tumours. Additionally, we propose that mutant POLE asserts a mutator phenotype specifically at 5mCs, and we find coding mutation hotspots in POLE-mutant cancers at highly-methylated CpGs in the tumour-suppressor genes APC and TP53. Finally, using multivariable regression models, we demonstrate that different cancers exhibit distinct mutation-methylation associations, with DNA repair influencing such associations in certain cancer genomes. Taken together, we find differential associations with methylation that are vital for accurately predicting expected mutation loads across cancer types. Our findings reveal links between methylation and common mutation and repair processes, with these mechanisms defining a key part of the mutational landscape of cancer genomes.Link_to_subscribed_fulltex

Bicycle helmets and risky behaviour : A systematic review

A long-standing argument against bicycle helmet use is the risk compensation hypothesis, i.e., increased feelings of safety caused by wearing a helmet results in cyclists exhibiting more risky behaviour. However, past studies have found helmet wearing is not associated with risky behaviour, e.g., committing a traffic violation was positively associated with a lower frequency of helmet use. There is a lack of consensus in the research literature regarding bicycle helmet use and the risk compensation hypothesis, although this gap in knowledge was identified in the early 2000s. This is the first study to carry out a systematic review of the literature to assess whether helmet wearing is associated with risky behaviour. Two study authors systematically searched the peer-reviewed literature using five research databases (EMBASE, MEDLINE, COMPENDEX, SCOPUS, and WEB OF SCIENCE) and identified 141 unique articles and four articles from other sources. Twenty-three articles met inclusion criteria and their findings were summarised. Eighteen studies found no supportive evidence helmet use was positively associated with risky behaviour, while three studies provided mixed findings, i.e., results for and against the hypothesis. For many of these studies, bicycle helmet wearing was associated with safer cycling behaviour. Only two studies conducted from the same research lab provided evidence to support the risk compensation hypothesis. In sum, this systematic review found little to no support for the hypothesis bicycle helmet use is associated with engaging in risky behaviour. (C) 2018 The Authors. Published by Elsevier Ltd.Peer reviewe

Women judging: is a young male drunk driver perceived as more negligent than a young female drunk driver?

Objective: It is well established that young men are the riskiest group of all drivers, and men in general more often drive under the influence of alcohol. However, potentially oversimplified representations such as a young male problem and drunk driving as a male problem can influence action and reinforce existing attitudes by selectively directing attention to stereotypically consistent behavior. The purpose of this study was to test the hypothesis of possible bias toward young male drivers in the context of drunk driving.Methods: We have created a scenario study investigating whether the sex of an imaginary young drunk driver would be associated with a different perceived negligence (ranging from 0=not negligent at all to 10=extremely negligent) among our participants. These participants were a representative sample of Finnish female driver's license holders. The data for the study were gathered as part of a larger survey study on women's drinking and driving culture.Results: Perceptions of how negligent a person was depended on the age of the respondents such that the older the respondent, the higher the perceived negligence. Perceived negligence was similar for male and female drivers in the scenario; however, there was an interaction effect between driver sex and the age of respondents. The youngest (20-29 years) and 2 oldest (50-69 years) groups of our respondents found the young woman to be more negligent, whereas the opposite occurred for the other 2 groups.Conclusions: The results of our imaginary scenario study of a representative sample of Finnish female driver's license holders do not support a hypothesis that there would be a negative bias toward young male drivers in the context of drunk driving behavior.Peer reviewe

Do people prefer cycling policy aiming at extending or saving lives? : An experimental survey study

We investigated the preference between transport policies aiming at extending vs. saving lives. In a 2 x 2 experimental survey study participants randomly received one of four possible policy combinations. The saving lives policy included saving five (250 life-years saved) or ten (500 life-years saved) lives of cyclists who are about 30 years of age. The extending lives policy through the promotion of cycling and associated health benefits was set to extend lives by two ratios (10:1 or 20:1) in relation to life-years saved of the life-saving strategy. Participants were representative of Finnish-speaking residents older than 15 years (N = 1025). In total, 45.5% of the participants preferred a policy aimed at saving lives, 36% preferred an extending lives policy, and 18.2% were undecided. These figures remained essentially the same independent of the benefit-to-cost ratio of cycling (in terms of saved life years) and whether the saving life policy meant saving five or ten lives. Women and the elderly preferred a policy aimed at saving lives, while cyclists preferred an extending lives policy. The results are discussed in the context of Vision Zero and a new transport paradigm called Vision Plus.Peer reviewe

Suicide by crashing into a heavy vehicle: Professional drivers’ views

Objective: Every profession has its own safety and health risks. In addition to the risk of being involved in a "normal" road crash, professional heavy vehicle drivers are at risk of becoming victims of people attempting suicide by crashing into their vehicles. Road suicides are not that rare, at least not in Finland, where they represent about 12% of all fatal road crashes. The purpose of this study was to survey professional heavy vehicle drivers about their experiences, views and opinions regarding road suicides. Methods: The sample included heavy vehicle drivers (N = 863) randomly recruited from a transport workers' union. Results: About 18% of the respondents reported a suspected suicide attempt of a motor vehicle driver crashing into their vehicle, with 15% of these (i.e.2.8% of the whole sample) also reporting a resulting crash. More than half of the respondents reported personally knowing another professional driver who had experienced a crash caused by a suicidal driver. Almost 80% of the drivers reported being afraid that someone would attempt suicide by crashing into their vehicle; however, thinking about such a possibility produces a level of anxiety in less than half of all respondents. Most respondents agreed about the challenges of avoiding a crash if somebody deliberately drives their car towards their vehicle. Conclusion: Heavy vehicle drivers perceive road suicides as an occupational risk in their profession. We discuss possible preventive measures against suicide attempts by crashing into a heavy vehicle.Peer reviewe

Suicide by crashing into a heavy vehicle : A one-year follow-up study of professional drivers

Train and heavy vehicle drivers can experience a traumatic event caused by people attempting suicide by crashing into their vehicles or jumping in front of them. While there are a number of studies on train drivers showing the negative consequences these events can have on their well-being, there are no studies on heavy vehicle drivers involved in these types of crashes. In the current study, we surveyed Finnish heavy vehicle drivers(N = 15) involved in a suicide crash in the year 2017 regarding their experiences and coping approximately one month (T1) and one year (T2) after the crash. Ten of these drivers reported one or various combinations of measurable consequences such as minor physical injuries, shorter or longer sickness absences, significant posttraumatic stress symptoms(measured using the Impact of Events Scale-Revised) and requiring psychological help. Posttraumatic stress symptoms decreased over time; however, three out of the four drivers who had a high IES-R score at T1 were still around the IES-R cut-off score at T2. This research raises questions whether and what kind of support heavy vehicle drivers who have been involved in a suicide crash should be givenPeer reviewe

API design for machine learning software: experiences from the scikit-learn project

Scikit-learn is an increasingly popular machine learning li- brary. Written in Python, it is designed to be simple and efficient, accessible to non-experts, and reusable in various contexts. In this paper, we present and discuss our design choices for the application programming interface (API) of the project. In particular, we describe the simple and elegant interface shared by all learning and processing units in the library and then discuss its advantages in terms of composition and reusability. The paper also comments on implementation details specific to the Python ecosystem and analyzes obstacles faced by users and developers of the library