Review of safety and mobility issues among older pedestrians

Safety analysis of pedestrians distracted by mobile phones at street crossings: Field study in Nanjing

The growing public concern over traffic safety hazards caused by pedestrians' distracted behavior, particularly related to mobile phone usage at pedestrian crossings. Through video recording of pedestrians' street-crossing behaviors on 12 sidewalks across 9 urban road intersections in Nanjing city, 1778 valid pedestrian samples were collected. The study categorizes mobile phone use during the crossing into five distinct types: no use, voice call, screen gaze, screen gaze with operation, and listening to music with headphones. Then, the effects of gender, age and companion conditions on the mobile phone during the crossing were examined by chi-square tests. Utilizing binomial logistic and Relogit regression models, the study analyzed the impact and safety risks of distraction on crossing behavior. Additionally, a random parameters (RP) logit model with heterogeneity in means was used to investigate the determinants affecting mobile phone usage. Notably, individuals aged 18 to 30 years were identified as the random parameter, while factors such as being under 18 years old, having a companion without interaction, having a companion with interaction, weekdays, sidewalk length, and the total number of other pedestrians were identified as fixed parameters. The study also presented significant variables affecting the probability of mobile phone usage through marginal effects, highlighting the potential safety risks associated with mobile phone usage during street crossing. These findings emphasize the need for heightened pedestrian safety awareness and a reduction in distracted behaviors to enhance overall traffic safety.

Age-Related Changes in the Utilization of Visual Information for Collision Prediction: A Study Using an Affordance-Based Model

The ability to predict collisions with moving objects deteriorates with aging. We followed the affordance-based model to identify optical variables that older adults had difficulty using for collision prediction. We reproduced a modified version of the interception task used in Steinmetz (Steinmetz, Layton, Powell, & Fajen, 2020, "Affordance-based versus current - future accounts of choosing whether to pursue or abandon the chase of a moving target," Journal of Vision, 20(3), 8) in a virtual reality (VR) environment and newly introduced perturbation for each of three optical variables (vertical and horizontal expansions of a moving object and the bearing angle produced between participants and a moving object). We expected that perturbation would negatively affect the performance only for those who rely on the optical variable to perform the interception task effectively. We tested 18 older and 15 younger adults and showed that older participants were not negatively affected by the perturbation for the vertical and horizontal expansion of a moving object, while they showed decreased performance when the perturbation was introduced with a bearing angle. These findings suggest that predicting collisions with moving objects deteriorates with aging because the perception of object expansion is impaired with aging.

Social Cognitive Theory, Driving Cessation, and Alternative Transportation in Later Life

Having viable alternative transportation options could help individuals stop driving when appropriate. This study employs the Social Cognitive Theory (SCT) to understand the barriers and facilitators of alternative transportation among a sample of adults aged 55 and older (N = 32). Using a daily transportation data collection app, MyAmble, the research team asked participants questions structured around environmental, individual, and behavioral factors as outlined in the SCT framework. Responses were analyzed using directed content analysis. Findings suggest a substantial reliance on motor vehicles and it was evident that many participants had never seriously considered what they would do if they could no longer drive. We posit that SCT principles may be applied to help older adults build self-efficacy to transition to driving cessation when needed.

The effect of age on injury patterns in pedestrian deaths

Although it is known that elderly pedestrians are at increased risk of injury and death from vehicle crashes the specific pattern of lethal injuries related to age has not been extensively studied. Data on the numbers of pedestrian fatalities and ages were obtained from 1990 to 2020 from the Traffic Accident Reporting System, The University of Adelaide, Adelaide, South Australia and detailed autopsy data on fatal pedestrian crashes from the pathology database at Forensic Science SA, Adelaide, South Australia from 2000 to 2020. Fatal injuries were separated into the following regions: head/face, spine, chest, abdomen and limbs/skeleton. Analysis of 634 cases of pedestrian fatalities (1990-2020) showed a significant decline in numbers over the years (p < 0.001). Analysis of fatal injuries in 219 cases (2000-2020) showed a significant reduction in the proportion of fatal head injuries with increasing age (p < 0.05), a significant increase in the proportion of fatal chest injuries with increasing age (p < 0.01) and a significant increase in the proportion of fatal limb/skeletal injuries with increasing age (p < 0.05). Older pedestrians are, therefore, more likely to sustain lethal chest and limb/skeletal injuries than head injuries compared to those who are younger, presumably due to greater physical fragility that occurs with age, with loss of protective muscle bulk and bone density.

Associations between walkability and pedestrian related injuries is modified by sociodemographic characteristics

BACKGROUND

Walkability scores have been developed to measure how well the characteristics of the physical environment support walking. However, because pedestrian safety is not taken into account, areas that have higher Walk Scores could be associated with more walking and also more pedestrian-related injury. We aimed to explore the association between Walk Score and pedestrian-related injury in Sydney.

METHOD

Pedestrian-related injuries from 2010 to 2018 in Sydney were identified in the New South Wales Combined Admitted Patient Epidemiology Data. Walk Score was used to measure area-level walkability in Sydney statistical division. Regression models were used to examine the association between Walk Score, pedestrian-related injury, length of hospital stay (LOS) and injury severity.

RESULT

Among people aged ≤64 years, there was no significant association between walkability score and pedestrian-related injury. Among people aged ≥ 65 years, walkability score was significantly positively associated with pedestrian-related injury, which peaked at Somewhat Walkable. For most disadvantaged areas, the risk of pedestrian-related injury was highest for areas that were classified as Somewhat Walkable. For moderately disadvantaged areas, the risk of pedestrian-related injury was highest at Very Walkable to Walker's Paradise areas. For the least disadvantaged areas, there was no significant association between walkability score and pedestrian-related injury. For LOS among people aged ≥ 65 years or in the most disadvantaged areas, it peaked at Somewhat Walkable areas. For injury severity, the risk of serious pedestrian-related injury was highest at Very Walkable to Walker's Paradise areas among people aged 16-64 years.

CONCLUSION

For the majority of the population, built environment characteristics that are considered to make walking attractive also make it safer, offsetting any exposure-related increase injury risk. However, this is not the case for people aged ≥ 19 years, and those living in socioeconomically disadvantaged areas. Incorporating measures of pedestrian safety in walkability scores may create an impetus to ensure that the built environment is designed to support the safety of pedestrians from these groups.

Disability and pedestrian road traffic injury: A scoping review

Disability and ableism remain a nascent area of inquiry in road traffic injury research. A scoping review of academic literature was conducted to understand the state of knowledge on disability and pedestrian-motor vehicle collisions. Sixty-two eligible articles were identified and included. A significantly higher risk of pedestrian collisions, injuries, and fatalities was consistently found among disabled people. Risk factors included individualized factors such as walking speed and crossing decisions of disabled people. The roles of social/political environments in injury risk were less commonly explored. More research is needed to assess how inaccessible or disabling environments may produce elevated risk of pedestrian injury among disabled populations.

Levels and Characteristics of Utilitarian Walking in the Central Areas of the Cities of Bologna and Porto

Walking is a mode of transport that offers many environmental and health benefits. Utilitarian walking refers to walking trips undertaken to fulfil routine purposes. The aim of this paper is to examine the extent to which walking is used as a transport mode for short urban trips in the city centers of Bologna and Porto and the barriers preventing utilitarian walking. Based on a questionnaire (n = 1117) administered in the two cities, results indicated that 21% of the individuals travel by foot, while 47% combine walking with other modes. This means that 68% of the daily trips to these city centers involve walking activity. From the overall trips, 84% were made to reach work and school/university. Statistical tests showed that utilitarian walkers were more likely to be females (p < 0.001) and undergraduates (p < 0.001). People from Bologna were more likely to engage in utilitarian walking than people from Porto (p < 0.001). Travel distance and time were the main barriers preventing people from engaging in utilitarian walking. The findings described in this paper provide a better understanding of utilitarian walking in the central areas of both cities, which can guide policies to promote healthier lifestyles and sustainable mobility.

Developmental differences across the lifespan in the use of perceptual information to guide action-based decisions

Perceptual information about unfolding events is important for guiding decisions about when and how to move in real-world action situations. As an exemplary case, road-crossing is a perceptual-motor task where age has been shown to be a strong predictor of risk due to errors in action-based decisions. The present study investigated age differences between three age groups (Children: 10-12 years old; Adults: 19-39 years old; Older Adults: 65 + year olds) in the use of perceptual information for selection, timing, and control of action when crossing a two-way street in an immersive, interactive virtual reality environment. Adults and children selected gaps to cross that were consistent with the use of a time-based information variable (tau), whereas older adults tuned less into the time-based variable (tau) to guide road-crossing decisions. For action initiation and control, children and adults also showed a strong ability to precisely time their entry with respect to the lead vehicle maximising the available time to cross and coordinating walking movements with the tail vehicle to ensure they were not on a collision course. In contrast, older adults delayed action initiation and showed difficulty coordinating self-movement with the approaching vehicle. This study and its results tie together age-based differences in the three components of action decision-making (selection, timing and control) within a unified framework based on perceptual information. The implications of these age-related differences in action decisions and crossing behaviours are discussed in the context of road safety.

The paradox of pedestrian's risk aversion

Traffic accidents are becoming a significant cause for unnatural deaths around the world, with more than 1.25 million fatalities in road accidents each year, and over 20 million people severely injured. A large portion of accidents that result in fatalities involve interaction between vehicles and pedestrians. In the literature, researchers speculate on a wide range of reasons for these figures. This paper focuses on the relationship between pedestrians' urgency to cross a busy road and the resulting level of risk for an accident. The probability for an accident is determined by a prediction model for a collision between drivers and pedestrians at congested conflict spots. The model is based on a motion planner called the Probabilistic Navigation Function (PNF), initially designed for robot navigation in dynamic cluttered and uncertain environments. The model predicts pedestrians' trajectories when crossing a busy road in a sub-meter accuracy, based on the risk they are willing to take (a reflection of the level of urgency to cross the road). The paper describes an unexpected and surprising pedestrian behavior in simple road crossings scenarios. When the model is given a loose risk boundary (that reflects a high level of pedestrian urgency to cross), the resulting trajectory exposes the pedestrian to a lower risk compared with a trajectory constructed with a strict risk boundary (that reflects a more conservative pedestrian). This is equivalent to claiming that, paradoxically, pedestrians in some scenarios who are willing to take higher levels of risk, face a decreased probability for an accident while crossing a congested road. The paper introduces the PNF model for crossing pedestrians, analyses their performance in a set of simulations, and explains its rationale. Next, an analytic estimation for the risk level as a function of the crossing angle of the selected trajectory is provided. A series of experiments conclude the paper and support the claim that this phenomenon is frequent among crossing pedestrians. The experimental results suggest that in some common scenarios, more cautious pedestrians may lower the initial risk for an accident at the expense of a total higher risk for an accident during the entire road crossing process, compared with a pedestrian who takes an initial higher level of risk that results in, overall, a decreased probability for an accident. A statistical analysis implies that there are significant differences in this occurrence between adults and children.

Accident Vulnerability and Vision for Action: A Pilot Investigation

Many accidents, such as those involving collisions or trips, appear to involve failures of vision, but the association between accident risk and vision as conventionally assessed is weak or absent. We addressed this conundrum by embracing the distinction inspired by neuroscientific research, between vision for perception and vision for action. A dual-process perspective predicts that accident vulnerability will be associated more strongly with vision for action than vision for perception. In this preliminary investigation, older and younger adults, with relatively high and relatively low self-reported accident vulnerability (Accident Proneness Questionnaire), completed three behavioural assessments targeting vision for perception (Freiburg Visual Acuity Test); vision for action (Vision for Action Test-VAT); and the ability to perform physical actions involving balance, walking and standing (Short Physical Performance Battery). Accident vulnerability was not associated with visual acuity or with performance of physical actions but was associated with VAT performance. VAT assesses the ability to link visual input with a specific action-launching a saccadic eye movement as rapidly as possible, in response to shapes presented in peripheral vision. The predictive relationship between VAT performance and accident vulnerability was independent of age, visual acuity and physical performance scores. Applied implications of these findings are considered.

Safe mobility, socioeconomic inequalities, and aging: A 12-year multilevel interrupted time-series analysis of road traffic death rates in a Latin American country

As the resources for road safety in developing countries are scarce and unevenly distributed, vulnerable road users -such as the elderly- may be particularly at risk of road traffic deaths. To date, the impact of road safety measures over the rate of road traffic deaths in older adults (60 years or older), considering the within-country socioeconomic inequalities, has not been explored in developing nations. This study takes the Chilean case as an example -with its 2005 traffic law reform as one of the road safety measures investigated-, in which open data available from official national sources for all its 13 regions over the 2002-2013 period were used for a multilevel interrupted time-series analysis. A statistically significant secular reduction of the rates of road traffic deaths in the elderly population was found (incidence rate ratio [IRR] 0.95, 95% confidence interval [CI] 0.91 to 0.99), but no evidence for a significant intercept or slope change after the traffic law reform was observed. Regions with the highest number of traffic offenses prosecuted in local police courts had lower rates of road traffic deaths in older adults (IRR 0.95, 95% CI 0.90 to 1.00), and those regions in the third (IRR 1.61, 95% CI 1.16 to 2.25) and the fifth (IRR 1.66, 95% CI 1.08 to 2.54) quintiles of socioeconomic deprivation had higher rates of road traffic deaths in the elderly. Such findings strongly support the conceptualization of the road safety of seniors in developing countries as a social equity issue, with implications for the design of traffic regulations and road environments.

Temperature and Rain Moderate the Effect of Neighborhood Walkability on Walking Time for Seniors in Barcelona

Walking is the most accessible form for seniors to engage in daily light or moderate physical activity. Walking activity depends on both individual and environmental factors, the latter including how walkable a given setting is. Recent papers have pointed at the relevance of also considering meteorological conditions in relation to the walking behavior of older adults. This paper explores the combined effect of neighborhood walkability, temperature and rain on daily walking time among seniors residing in Barcelona. Daily walking time was extracted from 7-day GPS (Global Positioning System) devices and accelerometer data of 227 seniors residing in the Barcelona Metropolitan Region (Spain). Temperature and rain data were extracted from official governmental weather stations. Mixed-effects linear regression models were adjusted to test the combined association between weather and walkability on daily walking time. Neighborhood walkability is positively associated with walking time among seniors, while rain generally deters it. Additionally, this study demonstrates that temperature and rain modify the effect of residential walkability on senior walking activity: low temperatures are particularly associated with lower walking activity among those residing in low walkable areas, while the presence of rain presents a negative association with walking time in high walkable environments. The combined effect of walkability and weather should be considered both in design actions that aim at improving walking infrastructure and also in prevention programs aimed at encouraging daily walking among seniors.

Elderly pedestrians' self-regulation failures and crash involvement: The development of typologies

The present study aims to identify, study, and develop typologies based on cases of elderly pedestrian collisions with vehicles where the pedestrians subjectively ascribe the collision at least in part to their own self-regulation failures. Semistructured interview surveys were conducted with 18 elderly people who had experienced a crash with a vehicle as a pedestrian aged 65 years or older. Personal construct theory is adopted as the theoretical underpinning, and it is assumed that pedestrians have their own subjective ways of making sense of the crashes they are involved in. It was found that 11 of the 18 participants ascribed the crashes at least in part to their own self-regulation failures. Cognitive maps of the 11 participants had a common structure, and the associated 11 incidents were classified with respect to the following dimensions: (a) self-regulation type, (b) self-regulation motivation, (c) cause of self-regulation failure, and (d) characteristics of the collisions that occurred after the self-regulation failure. Based on these findings, practical implications are found, and corresponding interventions that may reduce elderly pedestrian-vehicle crashes of this type are discussed. Specifically, this study demonstrates the necessity of education or other intervention that goes beyond informing elderly pedestrians of what is right and wrong in traffic environments. Another critical result-the need to motivate elderly pedestrians to respect and adhere to their own highly personal self-regulation, even if it is not against the social norms-is also presented and discussed.

Gait Speed with Anti-Slip Devices on Icy Pedestrian Crossings Relate to Perceived Fall-Risk and Balance

It is important to find criteria for preventive measures and appropriate assistive devices to reduce pedestrian injuries and increase walking in winter. Reducing the rate of falls on icy surfaces and improving people’s ability to safely cross a street in winter conditions by achieving an adequate walking speed, for example, need to be considered. This study explores pedestrian perceptions of fall risk, balance, and footfall transitions while using different designs for anti-slip devices on ice and snow-covered ice and relates these to measures of gait speed and friction. Trials were performed with nine pedestrians testing 19 anti-slip devices on ice and ice covered with snow. Laboratory tests of the dynamic coefficient of friction (DCOF) on plain ice were also performed. The findings suggest that there was conformity in the participants’ perceptions of good balance and low fall risk for one-fifth of the devices (three whole-foot designs and one design with built-in spikes). We also found that gait speed on icy pedestrian crossings is related to perceived fall-risk and balance control, but not to DCOF of the anti-slip devices.

How May Public Transport Influence the Practice of Everyday Life among Younger and Older People and How May Their Practices Influence Public Transport?

This paper examines public transport use through the lens of practice to understand the perspectives of two categories of public transport users: Younger and older people. In taking this approach, we assume that the forms of mobility in a society are dependent on citizens’ everyday practices and on the structures of the cities, landscapes, etc. Transport needs and accessibility may vary depending on contexts (i.e., where and how we live) and on the various resources of groups of citizens. Results indicated that younger people are repeatedly referred to public transport to meet their mobility needs, while older people are more often car-dependent. Local variations, among both younger and older people, indicate higher confidence in public transport in big and medium-sized cities and a greater desire for car ownership in small cities. For the transition to sustainable mobility, e.g., public transport, transport associations and local governments should be responsive to the practice of everyday life among citizens: e.g., younger people’s leisure activities in afternoons and weekends, and older people’s wish for accessible transport service outside the dominant flow of passengers and their daily commuting practice. The data come from Sweden, specifically from focus groups with teenagers aged 14–16 years and retired people aged 63–97 years.

Using Sensory Wearable Devices to Navigate the City: Effectiveness and User Experience in Older Pedestrians

Preserving older pedestrians’ navigation skills in urban environments is a challenge for maintaining their quality of life. However, the maps that are usually used by older pedestrians might be unsuitable to their specificities and the existing digital aids do not consider older people’s perceptual and cognitive declines or user experience. This study presents a rich description of the navigation experience of older pedestrians either with a visual (augmented reality glasses), auditory (bone conduction headphones), or a visual and haptic (smartwatch) wearable device adapted to age-related declines. These wearable devices are compared to the navigation aid older people usually use when navigating the city (their own digital or paper map). The study, with 18 participants, measured the navigation performance and captured detailed descriptions of the users’ experience using interviews. We highlight three main phenomena which impact the quality of the user experience with the four aids: (1) the shifts in attention over time, (2) the understanding of the situation over time, and (3) the emergence of affective and aesthetic feelings over time. These findings add a new understanding of the specificities of navigation experience by older people and are discussed in terms of design recommendations for navigation devices.

Effect of Rotating Auditory Scene on Postural Control in Normal Subjects, Patients With Bilateral Vestibulopathy, Unilateral, or Bilateral Cochlear Implants

Objective: The aim of this study was to investigate the impact of a rotating sound stimulation on the postural performances in normal subjects, patients with bilateral vestibulopathy (BVP), unilateral (UCI), and bilateral (BCI) cochlear implantees.

Materials and Methods: Sixty-nine adults were included (32 women and 37 men) in a multicenter prospective study. The group included 37 healthy subjects, 10 BVP, 15 UCI, and 7 BCI patients. The average of age was 47 ± 2.0 (range: 23–82). In addition to a complete audiovestibular work up, a dynamic posturography (Multitest Framiral, Grasse) was conducted in silence and with a rotating cocktail party sound delivered by headphone. The center of pressure excursion surface (COPS), sensory preferences, as well as fractal, diffusion, and wavelet analysis of stabilometry were collected.

Results: The rotating sound seemed to influenced balance in all subgroups except in controls. COPS increased with sound in the BVP and BCI groups in closed eyes and sway-referenced condition indicating a destabilizing effect while it decreased in UCI in the same condition suggesting stabilization (p < 0.05, linear mixed model corrected for age, n = 69). BVP had higher proprioceptive preferences, BCI had higher vestibular and visual preferences, and UCI had only higher vestibular preferences than controls. Sensory preferences were not altered by rotating sound.

Conclusions: The rotating sound destabilized BVP and BCI patients with binaural hearing while it stabilized UCI patients with monaural hearing and no sound rotation effect. This difference suggests that binaural auditory cues are exploited in BCI patients for their balance.

Providing a sustainable living environment in not-for-profit retirement villages

Purpose

As a viable housing option for older people, retirement villages need to provide a sustainable living environment that satisfies their residents’ needs in terms of affordability, lifestyle and environmental friendliness. This is, however, a significant challenge for not-for-profit developers because of the high upfront costs involved in using sustainable practices. The purpose of this paper is to identify the sustainable features and practices adopted in not-for-profit retirement villages.

Design/methodology/approach

Because of the lack of quantitative historical data, a case study approach was adopted to identify the sustainable features and practices used in a not-for-profit retirement village in Sunshine Coast, Queensland, Australia. Data were collected based on interviews, direct observation and documentation, and collected data were analysed by using content analysis.

Findings

The research findings indicate that similar to private developers, not-for-profit developers also have the capability to make their village environment sustainable. In this case, the sustainable practices cover various aspects including the selection of village location, site planning, provision of facilities and services, social life and living costs. Although the associated costs of adopting sustainable features is a concern for both developers and residents, some of the identified sustainable practices in this case do not result in significant cost increase but can improve the residents’ quality of life substantially.

Practical implications

The research findings provide a number of practical implications on how to deliver sustainable retirement villages in a not-for-profit village setting.

Originality/value

This paper provides a first look at sustainable features and practices adopted in both the development and operation stages of a not-for-profit retirement village.

Pedestrian safety in patients with Parkinson's disease: A case-control study

BACKGROUND

Patients with Parkinson's disease experience debilitating motor symptoms as well as nonmotor symptoms, such as cognitive dysfunction and sleep disorders. This constellation of symptoms has the potential to negatively influence pedestrian safety. The objective of this study was to investigate the association of motor symptoms, daytime sleepiness, impaired vigilance, and cognitive dysfunction with pedestrian behavior in patients with Parkinson's disease and healthy older adults.

METHODS

Fifty Parkinson's disease and 25 control participants were evaluated within a virtual reality pedestrian environment and completed assessments of motor performance, daytime sleepiness (Epworth Sleepiness Scale), vigilance (psychomotor vigilance task), and visual processing speed (Useful Field of View) outside the virtual reality environment. The primary outcome measure was time to contact, defined as the time remaining until a participant would have been hit by an approaching vehicle while crossing the virtual street.

RESULTS

The virtual reality pedestrian environment was feasible in all participants. Patients with Parkinson's disease demonstrated riskier pedestrian behavior compared with controls. Among Parkinson's disease participants, walking speed, objective measures of vigilance, and visual processing speed were correlated with pedestrian behavior, with walking speed the strongest predictor of time to contact, explaining 48% of the variance. Vigilance explained an additional 8% of the variance. In controls, vigilance was also important for street-crossing safety, but older age was the most robust predictor of pedestrian safety.

CONCLUSIONS

Walking speed is associated with unsafe pedestrian behavior in patients with Parkinson's disease. In contrast, age was the strongest predictor of pedestrian safety in healthy older adults. © 2017 International Parkinson and Movement Disorder Society.

A vibrotactile wristband to help older pedestrians make safer street-crossing decisions

INTRODUCTION

Older pedestrians are overrepresented in fatal accidents. Studies consistently show gap-acceptance difficulties, especially in complex traffic situations such as two-way streets and when vehicles approached rapidly. In this context, the present research was aimed at assessing the effectiveness of a vibrotactile device and study older pedestrian's behavior when wearing the wristband designed to help them make safer street-crossing decisions.

METHOD

Twenty younger-old participants (age 60-69), 20 older-old participants (age 70-80) and 17 younger adults (age 20-45) carried out a street-crossing task in a simulated two-way traffic environment with and without a vibrotactile wristband delivering warning messages.

RESULTS

The percentage of decisions that led to collisions with approaching cars decreased significantly when participants wore the wristband. Benefits tended to be greater particularly among very old women, with fewer collisions in the far lane and when vehicles approached rapidly when they wore the wristband. But collisions did not fall to zero, and responses that were in accordance with the wristband advice went up to only 51.6% on average, for all participants. The wristband was nevertheless considered useful and easy to use by all participants. Moreover, behavioral intentions to buy and use such a device in the future were greater in both groups of older participants, but not among the younger adults.

PRACTICAL APPLICATIONS

This haptic device was able to partly compensate for some age-related gap-acceptance difficulties and reduce street-crossing risks for all users. These findings could be fruitfully applied to the design of devices allowing communication between vehicles, infrastructures, and pedestrians.

Older adults must hurry at pedestrian lights! A cross-sectional analysis of preferred and fast walking speed under single- and dual-task conditions

Slow walking speed is strongly associated with adverse health outcomes, including cognitive impairment, in the older population. Moreover, adequate walking speed is crucial to maintain older pedestrians’ mobility and safety in urban areas. This study aimed to identify the proportion of Swiss older adults that didn’t reach 1.2 m/s, which reflects the requirements to cross streets within the green–yellow phase of pedestrian lights, when walking fast under cognitive challenge. A convenience sample, including 120 older women (65%) and men, was recruited from the community (88%) and from senior residences and divided into groups of 70–79 years (n = 59, 74.8 ± 0.4 y; mean ± SD) and ≥80 years (n = 61, 85.5 ± 0.5 y). Steady state walking speed was assessed under single- and dual-task conditions at preferred and fast walking speed. Additionally, functional lower extremity strength (5-chair-rises test), subjective health rating, and retrospective estimates of fall frequency were recorded. Results showed that 35.6% of the younger and 73.8% of the older participants were not able to walk faster than 1.2 m/s under the fast dual-task walking condition. Fast dual-task walking speed was higher compared to the preferred speed single- and dual-task conditions (all p < .05, r = .31 to .48). Average preferred single-task walking speed was 1.19 ± 0.24 m/s (70–79 y) and 0.94 ± 0.27 m/s (≥80 y), respectively, and correlated with performance in the 5-chair-rises test (r_s = −.49, p < .001), subjective health (τ = .27, p < .001), and fall frequency (τ = −.23, p = .002). We conclude that the fitness status of many older people is inadequate to safely cross streets at pedestrian lights and maintain mobility in the community’s daily life in urban areas. Consequently, training measures to improve the older population’s cognitive and physical fitness should be promoted to enhance walking speed and safety of older pedestrians.

"Outta my way!" Individual and environmental correlates of interactions between pedestrians and vehicles during street crossings

Because pedestrian crash rates remain lower than other collision types, surrogate measures such as traffic interactions are now used in road safety research to complement crash history. Using naturalistic data collection, we sought to assess 1) the likelihood of occurrence of interactions between pedestrians and vehicles based on individual and crossing characteristics; and 2) differences in interaction characteristics between children, adult and senior pedestrians. Observations of pedestrian crossing behaviours (n=4687) were recorded at 278 crossings. For recorded interactions (n=843), information was collected to characterize the behaviours of involved parties. A mixed-effect logit regression model was performed to assess the factors associated with interactions. Chi-square tests evaluated differences between age groups and characteristics of observed interactions. Older adults were those more likely to be involved in an interaction event. Bicycle paths, different crossing surface material and one-way streets were significantly associated with fewer interactions with vehicles, while parked vehicles nearby and crossings on arterial roads were significantly associated with more interactions. Children and the elderly (80 years of age or more) did have distinct patterns of interaction, with more careful drivers/cyclists behaviours being observed towards children and lesser regulation compliance towards the elderly. Given the growing emphasis and adoption of active transportation in many cities, the number of interactions between pedestrians and vehicles during street crossings is likely to increase. Educating drivers and pedestrians to respect each other's space requires an understanding of where, between whom, and under what circumstances interactions occur. Such an approach can also help identify which engineering and enforcement programs are needed to ensure safe pedestrian crossings since interactions can be good markers of uncomfortable crossing situations that may deter walking and lead to more collisions.

Gait speed and pedestrian crossings in COPD

The assumed minimum walking speed at pedestrian crossings is 1.2 m/s. In this prospective cohort study, usual walking speed was measured over a 4 m course in 926 community-dwelling, ambulatory patients with stable COPD. Mean (SD) walking speed was 0.91 (0.24) m/s with only 10.7% walking at a speed equal or greater than 1.2 m/s. In order for 95% of this cohort to safely negotiate a pedestrian cross, traffic lights would have to assume a minimum walking speed of 0.50 m/s (2.4 times longer than current times). The current assumed normal walking speed for pedestrian crossings is inappropriate for patients with COPD.

The studies were registered on clinicaltrials.gov and these data relate to the pre-results stage: NCT01649193, NCT01515709 and NCT01507415.

Effect of additional warning sounds on pedestrians' detection of electric vehicles: An ecological approach

Virtually silent electric vehicles (EVs) may pose a risk for pedestrians. This paper describes two studies that were conducted to assess the influence of different types of external sounds on EV detectability. In the first study, blindfolded participants had to detect an approaching EV with either no warning sounds at all or one of three types of sound we tested. In the second study, designed to replicate the results of the first one in an ecological setting, the EV was driven along a road and the experimenters counted the number of people who turned their heads in its direction. Results of the first study showed that adding external sounds improve EV detection, and modulating the frequency and increasing the pitch of these sounds makes them more effective. This improvement was confirmed in the ecological context. Consequently, pitch variation and frequency modulation should both be taken into account in future AVAS design.

Initiation of forward gait with lateral occurrence of emotional stimuli: general findings and relevance for pedestrians crossing roads

With reference to theoretical models regarding links between emotions and actions, the present study examined whether the lateral occurrence of an emotional stimulus influences spatial and temporal parameters of gait initiation in 18 younger and 18 older healthy adults. In order to simulate road-crossing hazard for pedestrians, slides of approaching cars were used and they were presented in counterbalanced order with threatening slides from the International Affective Picture System (IAPS) and control slides of safe walking areas. Each slide was presented on the left side of the participant once the first step was initiated. The results evidenced medio-lateral shifts to the left for the first step (right foot) and to the right for the second step (left foot). These shifts were both modulated by the slide contents in such a way that the resulting distance between the screen and the foot (right or left) was larger with the IAPS and traffic slides than with the control slides. The slides did not affect the base of support, step length, step velocity and time of double support. Advancing age influenced the subjective impact of the slides and gait characteristics, but did not modulate medio-lateral shifts. The data extend evidence of fast, emotional modulation of stepping, with theoretical and applied consequences.