Correlates of Helmet Use Among Recreation and Transportation Bicyclists

How Well Do Popular Bicycle Helmets Protect from Different Types of Head Injury?

Bicycle helmets are designed to protect against skull fractures and associated focal brain injuries, driven by helmet standards. Another type of head injury seen in injured cyclists is diffuse brain injuries, but little is known about the protection provided by bicycle helmets against these injuries. Here, we examine the performance of modern bicycle helmets in preventing diffuse injuries and skull fractures under impact conditions that represent a range of real-world incidents. We also investigate the effects of helmet technology, price, and mass on protection against these pathologies. 30 most popular helmets among UK cyclists were purchased within 9.99-135.00 GBP price range. Helmets were tested under oblique impacts onto a 45° anvil at 6.5 m/s impact speed and four locations, front, rear, side, and front-side. A new headform, which better represents the average human head's mass, moments of inertia and coefficient of friction than any other available headforms, was used. We determined peak linear acceleration (PLA), peak rotational acceleration (PRA), peak rotational velocity (PRV), and BrIC. We also determined the risk of skull fractures based on PLA (linear risk), risk of diffuse brain injuries based on BrIC (rotational risk), and their mean (overall risk). Our results show large variation in head kinematics: PLA (80-213 g), PRV (8.5-29.9 rad/s), PRA (1.6-9.7 krad/s2), and BrIC (0.17-0.65). The overall risk varied considerably with a 2.25 ratio between the least and most protective helmet. This ratio was 1.76 for the linear and 4.21 for the rotational risk. Nine best performing helmets were equipped with the rotation management technology MIPS, but not all helmets equipped with MIPS were among the best performing helmets. Our comparison of three tested helmets which have MIPS and no-MIPS versions showed that MIPS reduced rotational kinematics, but not linear kinematics. We found no significant effect of helmet price on exposure-adjusted injury risks. We found that larger helmet mass was associated with higher linear risk. This study highlights the need for a holistic approach, including both rotational and linear head injury metrics and risks, in helmet design and testing. It also highlights the need for providing information about helmet safety to consumers to help them make an informed choice.

Helmet wearing and related factors among electric personal mobility device users in Korea

Using data from the 2022 Korea Community Health Survey (n = 13 320), this study investigated helmet use and related factors among Korean adults using personal mobility devices, without distinguishing between private and hired users. Among mobility device users, 32.1% responded that they always wore a helmet. The proportion of helmet use was 35.2% among men, 25.8% among women, 29.2% among those aged 19-44 years, 42.3% among those aged 45-64 years and 26.6% among those aged 65 years or older. Furthermore, those who drank less frequently and were physically active were more likely to wear helmets. Moreover, people who always wore a seat belt when driving a car or sitting in the rear seat and people who always wore a helmet when riding a motorcycle were more likely to wear a helmet while using electric personal mobility devices. Approximately one-third of users always wore a helmet. The helmet-wearing rate was related to general characteristics such as gender and education level, and to safety behaviors such as wearing a seat belt when driving a car, sitting in the rear seat of a car, or when riding a motorcycle. In addition to considering personal characteristics investigated in this study, the helmet-wearing rate should be improved through policies or systems at the national or regional levels.

Risk factors associated with quadbike crashes: a systematic review

Background

Quadbikes or all-terrain vehicles are known for their propensity for crashes resulting in injury, disability, and death. The control of these needless losses resulting from quadbike crashes has become an essential contributor to sustainable development goals. Understanding the risk factors for such injuries is essential for developing preventive policies and strategies. The aim of this review was to identify the risk factors associated with quadbike crashes at multiple levels through a systematic review of a wide range of study designs.

Methods

The study incorporated a mixed-method systematic review approach and followed the PRISMA 2020 guidelines for reporting systematic reviews, including a peer reviewed  protocol. This systematic review included observational studies investigating the risk factors associated with quadbike crashes, injuries, or deaths. Seven electronic databases were searched from inception to October 2021. Studies were screened and extracted by three researchers. Quality appraisal was conducted using the Mixed Methods Appraisal Tool (MMAT). Due to extensive heterogeneity, meta-analysis was not conducted. All the risk factors have been presented in a narrative synthesis for discussion following the guidelines for Synthesis without Meta-analysis (SWiM).

Results

Thirty-nine studies combining an aggregate of 65,170 participants were included in this systematic review. The results indicate that modifiable risk factors, such as the increasing age of driving initiation, reducing substance use, and the use of organized riding parks, could reduce quadbike injuries. Riding practices such as avoiding passengers, avoiding nighttime riding, and using helmets could significantly reduce crashes and injuries among riders. Vehicle modifications such as increasing the wheelbase and limiting engine displacement could also help reduce crash incidence. Traditional interventional methods, such as legislation and training, had a weak influence on reducing quadbike injuries.

Conclusion

Multiple risk factors are associated with quadbike injuries, with most of them modifiable. Strengthening policies and awareness to minimize risk factors would help in reducing accidents associated with quadbikes.

PROSPERO registration number CRD42020170245

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 bicycle helmet legislation on injuries among crash involved cyclists were investigated by means of meta-analysis and the effects of several potential biases were investigated. The summary effect of mandatory bicycle helmet legislation for all cyclists on head injuries is a statistically significant reduction by 20% (95% confidence interval [-27; -13]). Larger effects were found for serious head injury (-55%; 95% confidence interval; [-78; -8]). Among children, larger effects were found when legislation applies to all cyclists than when it applies to children only. There is no clear indication of the results being affected by publication bias. Publication bias may exist, but any existing biases seem to more or less outweigh each other. Results from meta-analysis do not indicate that the results are systematically affected by a lack of control for time trend bias, choice of comparison group or study design (before-after vs. case control). Summary effects may be somewhat overestimated because of a lack of control for potential confounding variables in some of the studies. However, such a bias, if it exists, is not likely to be large. Empirical evidence for the hypotheses that mandatory bicycle helmet legislation deters people from cycling and that helmet wearing leads to behavioral adaptation is mixed. In summary, mandatory bicycle helmet legislation can be expected to reduce head injury among crash involved cyclists. Some adverse effects may occur, but will not necessarily be large or long-lasting. People who may be deterred from cycling, are among those with the highest injury risk and the smallest health effects from cycling. If the overall goal is to improve safety for all cyclists and to increase cycling, mandatory bicycle helmet legislation should be supplemented by other measures, especially improved bicycle infrastructure.

Bicycle helmet use patterns in Italy. A description and analysis of survey data from an Italian friends of cycling association

Cycling is becoming one of the most popular forms of recreation and transport the world over, but cyclists still have a high level of vulnerability. A bicycle helmet is an important safety device available to cyclists, but little is known regarding possible determinants of helmet use among adults. This study aims at providing information on helmet usage patterns in Italy and identifying the factors associated with bicycle helmet use. Data on 2072 bicycle riders from an Italian friends of cycling association aged 18 years or older who had ridden a bicycle in the last month were collected using an ad-hoc questionnaire via the web. The sample was equally distributed among subjects who always, most of the time, sometimes, rarely, or never use a helmet. To evaluate the association among socio-demographic and bicycle use characteristics and helmet use, a multinomial logistic regression model was performed. The results show a higher propensity to use a helmet among males, riders coming from Central and Southern Italy, people who cycles more than 60kilometres in a week, cyclists who have already had a crash, people who do not cycle daily or almost daily, riders of sport bikes. Moreover, the propensity to use a helmet increases with age. The survey provided a first step in approaching the lack of data on cycling behaviour and the wearing of a helmet in Italy.