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Fulltext International Physical Activity and Built Environment Study of adolescents: IPEN Adolescent design, protocol and measures

Cain KL, Salmon J, Conway TL, Cerin E, Hinckson E, Mitáš J, et al.

BMJ Open, 2021 01 18;11(1):e046636.
PMID: 33462102 DOI: 10.1136/bmjopen-2020-046636

INTRODUCTION: Only international studies can provide the full variability of built environments and accurately estimate effect sizes of relations between contrasting environments and health-related outcomes. The aims of the International Physical Activity and Environment Study of Adolescents (IPEN Adolescent) are to estimate the strength, shape and generalisability of associations of the community environment (geographic information systems (GIS)-based and self-reported) with physical activity and sedentary behaviour (accelerometer-measured and self-reported) and weight status (normal/overweight/obese).
METHODS AND ANALYSIS: The IPEN Adolescent observational, cross-sectional, multicountry study involves recruiting adolescent participants (ages 11-19 years) and one parent/guardian from neighbourhoods selected to ensure wide variations in walkability and socioeconomic status using common protocols and measures. Fifteen geographically, economically and culturally diverse countries, from six continents, participated: Australia, Bangladesh, Belgium, Brazil, Czech Republic, Denmark, Hong Kong SAR, India, Israel, Malaysia, New Zealand, Nigeria, Portugal, Spain and USA. Countries provided survey and accelerometer data (15 countries), GIS data (11), global positioning system data (10), and pedestrian environment audit data (8). A sample of n=6950 (52.6% female; mean age=14.5, SD=1.7) adolescents provided survey data, n=4852 had 4 or more 8+ hours valid days of accelerometer data, and n=5473 had GIS measures. Physical activity and sedentary behaviour were measured by waist-worn ActiGraph accelerometers and self-reports, and body mass index was used to categorise weight status.
ETHICS AND DISSEMINATION: Ethical approval was received from each study site's Institutional Review Board for their in-country studies. Informed assent by adolescents and consent by parents was obtained for all participants. No personally identifiable information was transferred to the IPEN coordinating centre for pooled datasets. Results will be communicated through standard scientific channels and findings used to advance the science of environmental correlates of physical activity, sedentary behaviour and weight status, with the ultimate goal to stimulate and guide actions to create more activity-supportive environments internationally.

Matched MeSH terms: Environment Design
Fulltext Pilot study to investigate the feasibility of the Home Falls and Accidents Screening Tool (HOME FAST) to identify older Malaysian people at risk of falls

Romli MH, Mackenzie L, Lovarini M, Tan MP

BMJ Open, 2016 08 16;6(8):e012048.
PMID: 27531736 DOI: 10.1136/bmjopen-2016-012048

OBJECTIVE: The relationship between home hazards and falls in older Malaysian people is not yet fully understood. No tools to evaluate the Malaysian home environment currently exist. Therefore, this study aimed to pilot the Home Falls and Accidents Screening Tool (HOME FAST) to identify hazards in Malaysian homes, to evaluate the feasibility of using the HOME FAST in the Malaysian Elders Longitudinal Research (MELoR) study and to gather preliminary data about the experience of falls among a small sample of Malaysian older people.
DESIGN: A cross-sectional pilot study was conducted.
SETTING: An urban setting in Kuala Lumpur.
PARTICIPANTS: 26 older people aged 60 and over were recruited from the control group of a related research project in Malaysia, in addition to older people known to the researchers.
PRIMARY OUTCOME MEASURE: The HOME FAST was applied with the baseline survey for the MELoR study via a face-to-face interview and observation of the home by research staff.
RESULTS: The majority of the participants were female, of Malay or Chinese ethnicity and living with others in a double-storeyed house. Falls were reported in the previous year by 19% and 80% of falls occurred at home. Gender and fear of falling had the strongest associations with home hazards. Most hazards were detected in the bathroom area. A small number of errors were detected in the HOME FAST ratings by researchers.
CONCLUSIONS: The HOME FAST is feasible as a research and clinical tool for the Malaysian context and is appropriate for use in the MELoR study. Home hazards were prevalent in the homes of older people and further research with the larger MELoR sample is needed to confirm the validity of using the HOME FAST in Malaysia. Training in the use of the HOME FAST is needed to ensure accurate use by researchers.

Matched MeSH terms: Environment Design/statistics & numerical data*
Physical Activity Among Adolescents in an East Malaysian Rural Indigenous Community: Exploring the Influence of Neighborhood Environmental Factors

Saimon R, Choo WY, Chang KH, Ng CJ, Bulgiba A

Asia Pac J Public Health, 2015 Nov;27(8 Suppl):33S-40S.
PMID: 25900978 DOI: 10.1177/1010539515582220

This study explores the rural environmental factors that influence adolescents' participation in physical activities (PA). Thirty-six indigenous adolescents, aged 13 to 17 years from rural communities of East Malaysia were involved in the photovoice procedures: photo-taking, selecting, contextualizing, and codifying themes. Despite being endowed with natural resources such as river, forest, hills, and so on, the adolescents and the community did not capitalize on these rich resources to promote and engage in PA. Poor maintenance of natural resources, the lack of pedestrian infrastructures and road safety, the lack of PA facilities, and negative perception of ancestors' agricultural activities were among factors that constrained adolescents' PA. Although basic amenities such as play spaces and pedestrian infrastructures are necessary to increase adolescents' PA, any intervention should make the most of the natural resources, which are cheaper, environment friendly, and sustainable.

Matched MeSH terms: Environment Design/statistics & numerical data*
Microsimulation modelling of driver behaviour towards alternative warning devices at railway level crossings

Tey LS, Zhu S, Ferreira L, Wallis G

Accid Anal Prev, 2014 Oct;71:177-82.
PMID: 24929822 DOI: 10.1016/j.aap.2014.05.014

Level crossings are amongst the most complex of road safety issues, due to the addition of rail infrastructure, trains and train operations. The differences in the operational characteristics of different warning devices together with varying crossing, traffic or/and train characteristics, cause different driver behaviour at crossings. This paper compares driver behaviour towards two novel warning devices (rumble strips and in-vehicle audio warning) with two conventional warning devices (flashing light and stop sign) at railway level crossings using microsimulation modelling. Two safety performance indicators directly related to collision risks, violation and time-to-collision, were adopted. Results indicated the active systems were more effective at reducing likely collisions compared to passive devices. With the combined application of driving simulation and traffic microsimulation modelling, traffic safety performance indicators for a level crossing can be estimated. From these, relative safety comparisons for the different traffic devices are derived, or even for absolute safety evaluation with proper calibration from field investigations.

Matched MeSH terms: Environment Design/statistics & numerical data*
Motorcycles entering from access points and merging with traffic on primary roads in Malaysia: behavioral and road environment influence on the occurrence of traffic conflicts

Abdul Manan MM

Accid Anal Prev, 2014 Sep;70:301-13.
PMID: 24831271 DOI: 10.1016/j.aap.2014.04.009

This paper uses data from an observational study, conducted at access points in straight sections of primary roads in Malaysia in 2012, to investigate the effects of motorcyclists' behavior and road environment attributes on the occurrence of serious traffic conflicts involving motorcyclists entering primary roads via access points. In order to handle the unobserved heterogeneity in the small sample data size, this study applies mixed effects logistic regression with multilevel bootstrapping. Two statistically significant models (Model 2 and Model 3) are produced, with 2 levels of random effect parameters, i.e. motorcyclists' attributes and behavior at Level 1, and road environment attributes at Level 2. Among all the road environment attributes tested, the traffic volume and the speed limit are found to be statistically significant, only contributing to 26-29% of the variations affecting the traffic conflict outcome. The implication is that 71-74% of the unmeasured or undescribed attributes and behavior of motorcyclists still have an importance in predicting the outcome: a serious traffic conflict. As for the fixed effect parameters, both models show that the risk of motorcyclists being involved in a serious traffic conflict is 2-4 times more likely if they accept a shorter gap to a single approaching vehicle (time lag <4s) and in between two vehicles (time gap <4s) when entering the primary road from the access point. A road environment factor, such as a narrow lane (seen in Model 2), and a behavioral factor, such as stopping at the stop line (seen in Model 3), also influence the occurrence of a serious traffic conflict compared to those entering into a wider lane road and without stopping at the stop line, respectively. A discussion of the possible reasons for this seemingly strange result, including a recommendation for further research, concludes the paper.

Matched MeSH terms: Environment Design*
Exploring the effects of roadway characteristics on the frequency and severity of head-on crashes: case studies from Malaysian federal roads

Hosseinpour M, Yahaya AS, Sadullah AF

Accid Anal Prev, 2014 Jan;62:209-22.
PMID: 24172088 DOI: 10.1016/j.aap.2013.10.001

Head-on crashes are among the most severe collision types and of great concern to road safety authorities. Therefore, it justifies more efforts to reduce both the frequency and severity of this collision type. To this end, it is necessary to first identify factors associating with the crash occurrence. This can be done by developing crash prediction models that relate crash outcomes to a set of contributing factors. This study intends to identify the factors affecting both the frequency and severity of head-on crashes that occurred on 448 segments of five federal roads in Malaysia. Data on road characteristics and crash history were collected on the study segments during a 4-year period between 2007 and 2010. The frequency of head-on crashes were fitted by developing and comparing seven count-data models including Poisson, standard negative binomial (NB), random-effect negative binomial, hurdle Poisson, hurdle negative binomial, zero-inflated Poisson, and zero-inflated negative binomial models. To model crash severity, a random-effect generalized ordered probit model (REGOPM) was used given a head-on crash had occurred. With respect to the crash frequency, the random-effect negative binomial (RENB) model was found to outperform the other models according to goodness of fit measures. Based on the results of the model, the variables horizontal curvature, terrain type, heavy-vehicle traffic, and access points were found to be positively related to the frequency of head-on crashes, while posted speed limit and shoulder width decreased the crash frequency. With regard to the crash severity, the results of REGOPM showed that horizontal curvature, paved shoulder width, terrain type, and side friction were associated with more severe crashes, whereas land use, access points, and presence of median reduced the probability of severe crashes. Based on the results of this study, some potential countermeasures were proposed to minimize the risk of head-on crashes.

Matched MeSH terms: Environment Design/statistics & numerical data*
Analysis of developed transition road safety barrier systems

Soltani M, Moghaddam TB, Karim MR, Sulong NH

Accid Anal Prev, 2013 Oct;59:240-52.
PMID: 23820073 DOI: 10.1016/j.aap.2013.05.029

Road safety barriers protect vehicles from roadside hazards by redirecting errant vehicles in a safe manner as well as providing high levels of safety during and after impact. This paper focused on transition safety barrier systems which were located at the point of attachment between a bridge and roadside barriers. The aim of this study was to provide an overview of the behavior of transition systems located at upstream bridge rail with different designs and performance levels. Design factors such as occupant risk and vehicle trajectory for different systems were collected and compared. To achieve this aim a comprehensive database was developed using previous studies. The comparison showed that Test 3-21, which is conducted by impacting a pickup truck with speed of 100 km/h and angle of 25° to transition system, was the most severe test. Occupant impact velocity and ridedown acceleration for heavy vehicles were lower than the amounts for passenger cars and pickup trucks, and in most cases higher occupant lateral impact ridedown acceleration was observed on vehicles subjected to higher levels of damage. The best transition system was selected to give optimum performance which reduced occupant risk factors using the similar crashes in accordance with Test 3-21.

Matched MeSH terms: Environment Design/standards*
Applying a random parameters Negative Binomial Lindley model to examine multi-vehicle crashes along rural mountainous highways in Malaysia

Rusli R, Haque MM, Afghari AP, King M

Accid Anal Prev, 2018 Oct;119:80-90.
PMID: 30007211 DOI: 10.1016/j.aap.2018.07.006

Road safety in rural mountainous areas is a major concern as mountainous highways represent a complex road traffic environment due to complex topology and extreme weather conditions and are associated with more severe crashes compared to crashes along roads in flatter areas. The use of crash modelling to identify crash contributing factors along rural mountainous highways suffers from limitations in data availability, particularly in developing countries like Malaysia, and related challenges due to the presence of excess zero observations. To address these challenges, the objective of this study was to develop a safety performance function for multi-vehicle crashes along rural mountainous highways in Malaysia. To overcome the data limitations, an in-depth field survey, in addition to utilization of secondary data sources, was carried out to collect relevant information including roadway geometric factors, traffic characteristics, real-time weather conditions, cross-sectional elements, roadside features, and spatial characteristics. To address heterogeneity resulting from excess zeros, three specialized modelling techniques for excess zeros including Random Parameters Negative Binomial (RPNB), Random Parameters Negative Binomial - Lindley (RPNB-L) and Random Parameters Negative Binomial - Generalized Exponential (RPNB-GE) were employed. Results showed that the RPNB-L model outperformed the other two models in terms of prediction ability and model fit. It was found that heavy rainfall at the time of crash and the presence of minor junctions along mountainous highways increase the likelihood of multi-vehicle crashes, while the presence of horizontal curves along a steep gradient, the presence of a passing lane and presence of road delineation decrease the likelihood of multi-vehicle crashes. Findings of this study have significant implications for road safety along rural mountainous highways, particularly in the context of developing countries.

Matched MeSH terms: Environment Design*
Evaluating the effect of lane width and roadside configurations on speed, lateral position and likelihood of comfortable overtaking in exclusive motorcycle lane

Ibrahim MKA, Hamid H, Law TH, Wong SV

Accid Anal Prev, 2018 Feb;111:63-70.
PMID: 29172046 DOI: 10.1016/j.aap.2017.10.023

Construction of exclusive motorcycle lanes is one of the measures to reduce motorcycle fatalities. Previous studies highlighted the risk of crashes with roadside objects and the tendency of motorcyclists to ride with excessive speed on exclusive motorcycle lanes. However, the risk of same-direction crashes on exclusive motorcycle lanes was not explored in much detail, especially on the impact of lane geometry and roadside configurations. This study used naturalistic riding data to determine the effects of lane width and roadside configurations on overtaking speed, lateral position and likelihood of comfortable overtaking on tangential sections of an exclusive motorcycle lane. Twenty-nine recruited motorcyclists rode the instrumented motorcycles along a 20km stretch of an exclusive motorcycle lane along a major urban road. Results revealed that both the roadside configurations and lane width significantly affect the participants' lateral position, while the roadside configurations only affects the overtaking speed. Participants' overtaking speeds and the front motorcycles' lateral position contribute significantly to the likelihood of comfortable overtaking in exclusive motorcycle lanes. The findings highlight the importance of micro-level behavior indicators in improving the design and overall safety of the exclusive motorcycle facility.

Matched MeSH terms: Environment Design*