Observing physical activity in suburbs

This study examined the reliability of the block walk method (BWM) for observing physical activity on suburban sidewalks/streets. Trained observers simultaneously walked 40 sidewalk/street segments each 1525 m in length at a pace of 30.5 m/min while recording the number of individuals walking/bicycling/jogging and the address where the activity occurred. An activity was observed at 2.9% of the 1020 addresses walked passed. In all 41 individuals were seen walking, 4 jogging, and 3 bicycling during 400 observation minutes. Agreements were 80%, 90%, and 86.7% for address, activity type, and number of individuals. The BWM is reliable for assessing activity on suburban sidewalks/streets.     

Characteristics of Urban Sidewalks/Streets and Objectively Measured Physical Activity

Several studies have found significant relationships between environmental characteristics (e.g., number of destinations, aesthetics) and physical activity. While a few of these studies verified that the physical activities assessed were performed in the environments examined, none have done this in an urban, neighborhood setting. This information will help efforts to inform policy decisions regarding the design of more “physically active” communities. Fourteen environmental characteristics of 60, 305-m-long segments, located in an urban, residential setting, were directly measured using standardized procedures. The number of individuals walking, jogging, and biking in the segments was assessed using an observation technique. The segments were heterogeneous with regards to several of the environmental characteristics. A total of 473 individuals were seen walking, bicycling, or jogging in the segments during 3,600 min of observation (60 min/segment). Of the 473 seen, 315 were walking, 116 bicycling, and 42 jogging. A greater number of individuals were seen walking in segments with more traffic, sidewalk defects, graffiti, and litter and less desirable property aesthetics. Only one environmental characteristic was associated with bicycling and none were significantly related with jogging. This study provides further evidence that environmental characteristics and walking are related. It also adds new information regarding the importance of scale (e.g., micro, macro) and how some environmental characteristics of urban, residential sidewalks and streets relate to physical activity. Suminski and Hyder are with the Department of Physiology, Kansas City University of Medicine and Biosciences, Kansas, MO, USA; Heinrich is with the Department of Public Health Sciences, John A. Burns School of Medicine, University of Hawaii at Manoa, Honolulu, HI, USA; Poston is with the Department of Basic Medical Sciences, University of Missouri-Kansas City School of Medicine, Kansas, MO, USA; Pyle is with the Department of Family Medicine, Kansas City University of Medicine and Biosciences, Kansas, MO, USA.     

Asociación entre las características del entorno de residencia y la actividad física

Objective

To assess the relationship between the physical and social attributes of the neighborhood environment and levels of total physical activity (PA), leisure time PA, and active commuting PA in adults.

Methods

The present cross-sectional study comprised 1500 adults (51.1% women) aged 15-74 years from the Autonomous Region of Madrid (Spain). Data were collected through a structured telephone interview. PA was assessed using the Global Physical Activity Questionnaire, version 2. Neighborhood attributes were assessed with the Environmental Module of the International Physical Activity Prevalence Study.

Results

The factors associated with a higher probability of achieving moderate to high levels of total PA and active commuting PA were living in high density residential areas, the presence of shops close to the residential area, public transport stops 10-15 minutes away from the home, and the existence of sidewalks in most of the neighborhood's streets (all p <0,05). The factors associated with moderate to high leisure time PA levels were the presence of active people in the residential area and the presence of low-cost recreational facilities (both p <0,05).

Conclusions

Our findings suggest that most of the physical and social attributes of the neighborhood environment examined in this study are associated with total and active commuting PA, whereas only certain neighborhood attributes seem to be associated with leisure time PA.     

Barriers to children walking and biking to school--United States, 1999

Physical activity is an important part of a healthy lifestyle; however, many children in the United States do not meet recommended levels of physical activity. Although walking and biking to school can increase physical activity among children, motor-vehicle traffic and other factors can make these activities difficult. The majority of U.S. children do not walk or bike to school, approximately one third ride a school bus, and half are driven in a private vehicle. Less than one trip in seven is made by walking or biking. To examine why the majority of children do not walk or bike to school, CDC analyzed data from the national HealthStyles Survey. This report summarizes the results of that analysis, which indicate that long distances and dangerous motor-vehicle traffic pose the most common barriers to children walking and biking to school. Public health and community-based efforts that encourage walking and biking to school should address these barriers.     

Development of a reliable measure of walking within and outside the local neighborhood: RESIDE's Neighborhood Physical Activity Questionnaire

BACKGROUND: The RESIDential Environment project (RESIDE) is a longitudinal study evaluating the impact of a new residential design code on walking. OBJECTIVE: To develop a reliable measure of walking--undertaken within and outside the neighborhood--and overall physical activity. METHODS: A test-retest reliability study was undertaken (n = 82, mean age 39 years). The instrument was based on the International Physical Activity Questionnaire (IPAQ-short version) and Active Australia Survey. It measured usual frequency and duration of (1) recreational- and transport-related walking within and outside the neighborhood and (2) other vigorous and moderate physical activities. RESULTS: Reliability of recall of whether participants had walked within (k = 0.84) and outside (0.73) the neighborhood was acceptable. Similarly, recall of frequency and duration of transport and recreational-related walking within the neighborhood was excellent (ICC > or = 0.82), as was recall of transport-related walking trips outside the neighborhood (ICC > or = 0.84). Reliability for duration of recreational walking outside the neighborhood was fair to good (ICC = 0.55). The reliability of indices of total physical activity based on MET min/week (ICC = 0.82) and MET min/week dichotomized to 'sufficient' physical activity for health (kappa = 0.67) were both acceptable. CONCLUSIONS: The Neighborhood Physical Activity Questionnaire (NPAQ) is sufficiently reliable for studies examining environmental correlates of walking within the neighborhood.     

Critical factors for active transportation to school among low-income and minority students. Evidence from the 2001 National Household Travel Survey

BACKGROUND: Walking to school may be an important source of daily physical activity in children's lives, and government agencies are supporting programs to encourage walking to school (e.g., Safe Routes to School and the CDC's KidsWalk programs). However, little research has looked at differences in behavior across racial/ethnic and income groups. METHODS: This cross-sectional study used data from the 2001 National Household Travel Survey to document rates of walking and biking to school among low-income and minority youth in the U.S. (N=14,553). Binary models of the decision to use active transport to school were developed to simultaneously adjust for trip, individual, household, and neighborhood correlates. All analyses were conducted in 2007. RESULTS: The data showed that low-income and minority groups, particularly blacks and Hispanics, use active travel modes to get to school at much higher rates than whites or higher-income students. However, racial variation in travel patterns is removed by controlling for household income, vehicle access, distance between home and school, and residential density. CONCLUSIONS: Active transportation to school may be an important strategy to increase and maintain physical activity levels for low-income and minority youth. Current policy interventions such as Safe Routes to School have the opportunity to provide benefits for low-income and minority students who are the most likely to walk to school.     

Environmental and Social Determinants of Youth Physical Activity Intensity Levels at Neighborhood Parks in Las Vegas,NV

Parks can play an important role in youth activity. This study used observational data to evaluate the relationship of environmental and social determinants to youth physical activity intensity levels in Las Vegas neighborhood parks. System for observing play and leisure activity in youth was used to code activity levels as sedentary, walking, or vigorous in five low-income and five high-income parks. Environmental determinants included amenities, incivilities, size, high-speed streets, sidewalk condition, and temperature. Social determinants included percent minority and Hispanic, gender, and income. A multinomial logistic regression model was performed. We observed 1,421 youth, 59 % male, 41 % female; 21 % were sedentary, 38 % walking, and 41 % vigorous. Males were more likely to be observed walking (OR 1.42) and vigorous (OR 2.21) when compared to sedentary. High-speed streets (OR 0.76), sidewalks condition (OR 0.34), and low-income neighborhoods (OR 0.07) was associated with decreased odds of vigorous activity; incivilities (OR 1.34) and amenities (OR 1.27) were associated with greater odds of being vigorous. Environmental and social determinants are associated with physical activity intensity levels at parks. Stakeholders should ensure quality parks, as they relate to physical activity levels in youth. Understanding environmental and social determinants that influence physical activity at parks is critical to utilizing their full potential in an effort to combat childhood obesity.     

Environmental correlates of physical activity in a sample of Belgian adults

PURPOSE: This study investigated the variance in sitting, walking, and moderate and vigorous physical activity explained by neighborhood design and recreational environmental variables above and beyond the variance accounted for by individual demographic variables. DESIGN: Cross-sectional analyses of self-reported survey data. SETTING: A random sample of inhabitants of Ghent, Belgium, aged 18-65 years, was drawn. SUBJECTS: Five hundred twenty-one adults completed questionnaires (52.1% response rate). The average age of the sample was 41 years, and 48.2% were female. MEASURES: A questionnaire developed to assess neighborhood design and recreational environmental variables with a total of 81 items was administered. The environmental questionnaire showed acceptable to good reliability and acceptable validity. The previously validated International Physical Activity Questionnaire (IPAQ) was used to quantify physical activity in the past 7 days. Additional demographic information was also obtained. RESULTS: Regression analyses showed that environmental variables were related to all types of physical activity in both sexes. However, the range of variance explained by the models including demographic and environmental variables was low, only 5% to 13%. Minutes of walking and of moderate-intensity activity were related to quality of sidewalks and accessibility of shopping and public transportation. Vigorous physical activity was related to presence of activity supplies in the home and number of convenient activity facilities outside the home. CONCLUSIONS: Both neighborhood design and recreational environment variables had small but significant associations with multiple types of physical activity in a sample of Belgian adults.     

The relative influence of individual,social and physical environment determinants of physical activity

Environmental determinants of health are receiving growing attention in the literature, although there is little empirical research in this area. The Study on Environmental and Individual Determinants of Physical Activity (known as the SEID project) was a social ecological project that examined the relative influence of individual, social environmental and physical environmental determinants of recreational physical activity. It involved a community survey of 1803 healthy workers and home-makers aged 18-59 years living in a 408 km2 area of metropolitan Perth, Western Australia. Physical environmental determinants were mainly conceptualised as spatial access to popular recreational facilities. Overall, 59% of respondents exercised as recommended. Recreational facilities located near home were used by more respondents than facilities located elsewhere. The most frequently used facilities were informal: the streets (45.6%); public open space (28.8%) and the beach (22.7%). The physical environment's directs the influence on exercising as recommended was found to be secondary to individual and social environmental determinants. Nevertheless, accessible facilities determined whether or not they were used and in this way, support and enhance the achievement of recommended levels of physical activity behaviour by providing opportunities. The results suggest that access to a supportive physical environment is necessary, but may be insufficient to increase recommended levels of physical activity in the community. Complementary strategies are required that aim to influence individual and social environmental factors. Given the popularity of walking in the community, it is recommended that greater emphasis be placed on creating streetscapes that enhance walking for recreation and transport.     

Comparison of two methods of assessing physical activity in the Coronary Artery Risk Development in Young Adults (CARDIA) Study

Physical activity was assessed by questionnaire among 4,956 young blacks and whites aged 18-30 years at the baseline examination (1985-1986) of the Coronary Artery Risk Development in Young Adults (CARDIA) study, a longitudinal study of cardiovascular risk factors. The Physical Activity Recall questionnaire categorized all activity during the previous week, while the Physical Activity History questionnaire quantified participation in 13 specific activities during the previous year. This report compares the two questionnaires with regard to their characterization of the activity levels of the sociodemographic subgroups of the study population and their associations with known physiologic correlates of physical activity. Both questionnaires resulted in the same physical activity patterns for sex (men greater than women) and age (younger greater than older) strata. However, the mean Physical Activity History score was higher in white women than in black women, while the Physical Activity Recall scores were nearly equal. The Physical Activity History score was directly related to educational status, and the Physical Activity Recall score was inversely related to educational status. The Physical Activity History score was generally more strongly associated with physiologic variables known to be related to physical activity (e.g., treadmill test duration). Based upon these findings, which may only be appropriate in this age group, it was concluded that the Physical Activity History score was the more valid measure of habitual physical activity in this study group of young adults.     

Associations of physical activity with neighborhood environments and transportation modes in older Japanese adults

Objective

We investigated associations of walking and other leisure-time physical activity (LTPA) with environmental characteristics and transportation modes in older Japanese adults.

Methods

This cross-sectional study in 2010-2011 used data from 421 community-dwelling older adults aged 65-85 years living in Kasama City, rural Japan. We used the Physical Activity Scale for the Elderly to assess walking and other LTPAs, and the International Physical Activity Questionnaire Environment Module for neighborhood environments.

Results

After adjusting for confounders, we found that good traffic safety and aesthetics were positively associated with high levels of walking (ORs = 1.64-2.12); whereas, good access to public transportation was negatively associated with walking (OR = 0.64, 95% CI = 0.42-0.98). Good access to recreational facilities, presence of sidewalks, absence of hills, seeing people exercise, and aesthetically pleasing surroundings were positively associated with high levels of LTPA except walking (ORs = 1.61-2.13). Individuals who rode bicycles more than once per week were more likely to engage in a LTPA except walking (1-3 days: OR = 1.72, 95% CI = 1.03-2.87; ≥ 4 days: OR = 2.90, 95% CI = 1.71-4.93).

Conclusion

This study adds information on correlates of physical activity among older Japanese adults; the positive association between LTPA except walking and the frequency of bicycle travel is an especially new and intriguing finding.     

A study of urban housing demolition as a source of lead in ambient dust on sidewalks, streets, and alleys

We examined changes in ambient dust lead (Pb) levels associated with the demolition of older row houses containing lead paint in Baltimore, MD, USA. Our previous paper describes the three study sites, the demolition processes, and increases in the Pb dustfall rate during demolition (>40-fold) and debris removal (>6-fold) within 10 m of sites where wetting was of limited effectiveness. This paper presents the analysis of settled dust collected using a cyclone device from streets, sidewalks, and alleys within 100 m of study sites before, immediately after, and 1 month after demolition. We found acute increases in Pb loadings and dust loadings after demolition and debris removal that are of public health concern. Streets and alleys had the greatest increases in Pb loadings and the highest levels overall. At one site, geometric mean (GM) Pb loadings immediately after demolition increased 200% for streets to 8080 microg/ft(2), 138% for alleys to 6020 microg/ft(2), and 26% for sidewalks to 2170 microg/ft(2). One month after demolition, the GM Pb loadings for streets, alleys, and sidewalks were reduced on average by 41-67% from post-demolition levels and were below baseline levels for alleys and sidewalks. The other main site had smaller increases in GM Pb loadings immediately after demolition-18% for alleys to 1740 microg/ft(2) and 18% for sidewalks to 2050 microg/ft(2)-and a decrease of 29% for streets to 2730 microg/ft(2). Exterior dust is a public health concern because it is a pathway of ambient Pb exposure and a potential source of residential exposure via tracking and re-aerosolization and re-deposition. Our findings highlight the need to control demolition-related Pb deposition and to educate planners, contractors, and health and housing agencies. This is particularly important given the large numbers of aging US dwellings that will be razed as part of future urban redevelopment efforts.     

Relation Between Higher Physical Activity and Public Transit Use

Objectives. We isolated physical activity attributable to transit use to examine issues of substitution between types of physical activity and potential confounding of transit-related walking with other walking.Methods. Physical activity and transit use data were collected in 2008 to 2009 from 693 Travel Assessment and Community study participants from King County, Washington, equipped with an accelerometer, a portable Global Positioning System, and a 7-day travel log. Physical activity was classified into transit- and non–transit-related walking and nonwalking time. Analyses compared physical activity by type between transit users and nonusers, between less and more frequent transit users, and between transit and nontransit days for transit users.Results. Transit users had more daily overall physical activity and more total walking than did nontransit users but did not differ on either non–transit-related walking or nonwalking physical activity. Most frequent transit users had more walking time than least frequent transit users. Higher physical activity levels for transit users were observed only on transit days, with 14.6 minutes (12.4 minutes when adjusted for demographics) of daily physical activity directly linked with transit use.Conclusions. Because transit use was directly related to higher physical activity, future research should examine whether substantive increases in transit access and use lead to more physical activity and related health improvements.Physical inactivity is prevalent and a worldwide public health concern.1 Increasing active transport is an appealing strategy to increase overall physical activity, although more clarity is needed about the amount of physical activity directly attributable to transportation choices. Users of public transit (e.g., bus, train) engage in more overall physical activity than do nonusers and more often meet daily physical activity recommendations (≥ 30 min/d on most days), likely from the active transport involved with accessing transit (e.g., walking to a bus stop).2–5 Reported total walking time is also higher among transit users than among nonusers.4,6 National travel diary data indicate that the average American transit user (approximately 2%–3% of adults) walks 19 minutes per day to and from transit, and approximately one third of these transit users attain recommended levels of physical activity based solely on the amount of walking related to their transit use.2,3 Better public transit access and more use appear related to more overall physical activity and specifically walking.7However, many previous studies about the relation between transit use and physical activity fail to address the critical issues of possible confounding and potential substitution. Regarding confounding, examining only overall physical activity or total walking among transit users versus nonusers without disaggregating physical activity into constituent types and purposes of walking makes it difficult to determine how much physical activity is directly related to using public transit (i.e., walking or biking to and from public transit stops), separate from other types of utilitarian (e.g., walking to the store) or recreational physical activity. This is problematic because other factors could readily account for the relation between transit use and higher overall physical activity and walking. For example, built environment factors such as residential density and land use mix are related to transit use because transit access is higher in more dense and higher mix areas; however, these built environment variables are also related to walking to and from other nonresidential locations (e.g., stores, restaurants).8 Thus, without more precision, it is not possible to rule out a spurious relation (e.g., through built environment or other shared variables) between transit access and use and physical activity.The issue of substitution is also critical to measuring the health effect of transit use on physical activity. If transit users decrease the time spent in other activities in lieu of the time spent in transit-related walking, attempts to increase transit use would not yield increases in physical activity but merely shift from one form to another form of physical activity. Studies that provide more precise estimates of walking to and from transit use have not examined whether such substitution occurs. A recent US time use study suggested that some substitution may be happening as individuals with longer commutes, which are often characteristic of public transit use, engage in less recreational physical activity than do those with shorter commutes.9Large-scale randomized trials manipulating transit use are not feasible, but one approach to a better understanding of the relation between transit use and physical activity is to obtain an objective overall and type-specific assessment of physical activity among transit users and nonusers and, for the former, to examine walking behavior directly linked to transit use. For the current study, we hypothesized that transit users would be more physically active than nonusers and that increased activity would be directly linked to transit use (i.e., no or little confounding). Thus, we expected that physical activity would be higher among more frequent transit users than among less frequent users and that more physical activity would occur only on days when transit was used as a result of the transit-related physical activity and not changes in other types of physical activity (i.e., no or little substitution occurs).     

Exploring Associations between Physical Activity and Perceived and Objective Measures of the Built Environment

The built environment may be responsible for making nonmotorized transportation inconvenient, resulting in declines in physical activity. However, few studies have assessed both the perceived and objectively measured environment in association with physical activity outcomes. The purpose of this study was to describe the associations between perceptions and objective measures of the built environment and their associations with leisure, walking, and transportation activity. Perception of the environment was assessed from responses to 1,270 telephone surveys conducted in Forsyth County, NC and Jackson, MS from January to July 2003. Participants were asked if high-speed cars, heavy traffic, and lack of crosswalks or sidewalks were problems in their neighborhood or barriers to physical activity. They were also asked if there are places to walk to instead of driving in their neighborhood. Speed, volume, and street connectivity were assessed using Geographic Information Systems (GIS) for both study areas. Locations of crashes were measured using GIS for the NC study area as well. Objective and perceived measures of the built environment were in poor agreement as calculated by kappa coefficients. Few associations were found between any of the physical activity outcomes and perception of speed, volume, or presence of sidewalks as problems in the neighborhood or as barriers to physical activity in regression analyses. Associations between perceptions of having places to walk to and presence of crosswalks differed between study sites. Several associations were found between objective measures of traffic volume, traffic speed, and crashes with leisure, walking, and transportation activity in Forsyth County, NC; however, in Jackson, MS, only traffic volume was associated with any of the physical activity outcomes. When both objective and perceived measures of the built environment were combined into the same model, we observed independent associations with physical activity; thus, we feel that evaluating both objective and perceived measures of the built environment may be necessary when examining the relationship between the built environment and physical activity. McGinn is with the Department of Epidemiology and Population Health, Albert Einstein College of Medicine, Bronx, NY 10461, USA; Evenson and Huston are with the Department of Epidemiology, University of North Carolina, Chapel Hill, NC, USA; Herring is with the Department of Biostatistics, University of North Carolina, Chapel Hill, NC, USA; Rodriguez is with the Department of City and Regional Planning, University of North Carolina, Chapel Hill, NC, USA.     

Obesity, physical activity, and the urban environment: public health research needs

Persistent trends in overweight and obesity have resulted in a rapid research effort focused on built environment, physical activity, and overweight. Much of the focus of this research has been on the design and form of suburbs. It suggests that several features of the suburban built environment such as low densities, poor street connectivity and the lack of sidewalks are associated with decreased physical activity and an increased risk of being overweight. But compared to suburban residents, inner city populations have higher rates of obesity and inactivity despite living in neighborhoods that are dense, have excellent street connectivity and who's streets are almost universally lined with sidewalks.     

Socio-demographic and perceived environmental correlates of walking in Portuguese adults—A multilevel analysis

Several studies have identified associations between walking levels and socio-demographic and environmental variables. The aim of the present study was to describe walking patterns and examine associations between socio-demographic characteristics and perceived environmental attributes with walking among adults living in the Azorean Archipelago (Portugal). In all, 7330 adult participants (4104 women), aged 38.1±9.3 years, of the 2004 Azorean Physical Activity and Health Study answered the Environmental Module and the short version of the International Physical Activity Questionnaire. Among the Azoreans, the environmental dimension “infrastructures, access to destinations, social environment and aesthetics” and moderate to vigorous physical activity were positively associated with walking levels; and smoking, sitting time and being married were negatively related, regardless of gender, age or education level. Through the cross-sectional nature of this study, our results suggest that targeted programs for Azoreans aimed to increase walking levels should consider that infrastructures, access to destinations, social environment and aesthetics seem to act synergistically and associate positively with walking behaviour.     

Promoting active transportation as a partnership between urban planning and public health: the columbus healthy places program

Active transportation has been considered as one method to address the American obesity epidemic. To address obesity prevention through built-environment change, the local public health department in Columbus, Ohio, established the Columbus Healthy Places (CHP) program to formally promote active transportation in numerous aspects of community design for the city. In this article, we present a case study of the CHP program and discuss the review of city development rezoning applications as a successful strategy to link public health to urban planning. Prior to the CHP review, 7% of development applications in Columbus included active transportation components; in 2009, 64% of development applications adopted active transportation components specifically recommended by the CHP review. Active transportation recommendations generally included adding bike racks, widening or adding sidewalks, and providing sidewalk connectivity. Recommendations and lessons learned from CHP are provided.     

Does context moderate physical activity's relations with depression?: A cross-sectional study

BackgroundPhysical activity is a well-established protective factor and treatment for depression. However, past research suggested that the context of physical activity might moderate relations with depression. Addressing this possibility directly, the hypothesis that physical activity occurring during recreation, versus during transportation or work, is more strongly negatively correlated with depression was tested.MethodData were drawn from six, two-year cycles of the National Health and Nutrition Examination Survey (years 2007–2018), yielding a national sample of adults 20 years and older in the United States (N = 26,842). Participants completed structured interviews assessing physical activity in three contexts (work, recreation, and transportation) and depressive symptomatology. The study design was cross-sectional and observational.ResultsSupporting the hypothesis, substantive physical activity during recreation (e.g., fitness, sports; odds ratio = 0.57) was a stronger predictor of diagnostic-level depressive symptomatology than was physical activity during work (e.g., paid work, unpaid chores; odds ratio = 0.98) or during transportation (e.g., walking, biking to get places; odds ratio = 0.93). Analyses controlled for age, gender, ethnicity, education, income, smoking, body mass index, and employment status.ConclusionsThe context of physical activity moderates relations between physical activity and depression. These findings raise the possibility that individuals who engage in physical activity only at work or for transportation, but not for recreation, may not receive significant mood benefits from physical activity.     

Traditional Physical Activity Indexes Derived from the Harvard Alumni Activity Survey Have Low Construct Validity in a Lower Income,Urban Population

The purpose of this study is to investigate the construct validity of the Harvard Alumni Activity Survey (HAAS) in an urban, lower income population. Data were collected from 192 smokers enrolled in an antioxidant micronutrient trial. Activity data were compared to body mass index (BMI), diastolic, and systolic blood pressure. The traditional physical activity index (PAI), using data on stair climbing, walking, and sports, was calculated including and excluding body mass. A new scale, the total weekly activity (TWA) scale, was derived from other questions on the HAAS. The PAI scale calculated with body mass was unassociated with BMI and blood pressure. The PAI scale calculated without body mass was unassociated with BMI and systolic blood pressure but was associated with diastolic blood pressure (Beta = −0.001, p = 0.03). The TWA scale was associated with BMI (Beta = −0.01, p = 0.01), diastolic (Beta = −0.03, p = 0.01), and systolic blood pressure (Beta = −0.04, p = 0.01). A one standard deviation change in the TWA scale is predicted to be equivalent to a change of 0.99 BMI units, 2.97 mmHg of diastolic blood pressure, and 3.96 mmHg of systolic blood pressure. This work suggests that the TWA scale has greater construct validity than the traditional PAI scale in this population. Rundle is with the Department of Epidemiology, Mailman School of Public Health, Columbia University, New York, NY, USA; Hagins is with the Division of Physical Therapy, School of Health Professions, Long Island University, Brooklyn Campus, Brooklyn, NY, USA; Orjuela, Mooney, Kim, and Perera are with the Department of Environmental Health Sciences, Mailman School of Public Health, Columbia University, New York, NY, USA.     

中国12个城市中心城区步行道设置情况调查

目的 了解中国12个城市中心城区步行道配备、维护情况及其与城市经济水平、区域居住密度和街道繁荣程度间的关联。方法 以北京、天津、上海、青岛、杭州、绍兴、苏州、南通、镇江、成都、西宁、哈尔滨共12个城市的54个中心城区333个调查点内所有的道路为调查对象,于2012年采用观察法调查道路两侧步行道的配备及维护情况。结果 共有4 255条路段纳入分析,其中有71.1%的路段配有步行道。12个城市中配备步行道的路段比例最高的城市为青岛（91.9%）和哈尔滨（90.6%）,最低的是苏州（48.6%）和绍兴（52.6%）。12个城市在步行道配备及维护各方面差异均有统计学意义,高经济水平城市的步行道配备和路面维护情况较好、阻碍较少,但步行道隔离连续性较差、划线停车较多。相比低居住密度区域,高居住密度区域的步行道隔离连续性较差、步行道较窄,同时划线停车和阻碍较多。道路繁荣度越高,步行道配备和步行道宽度的情况越好,但隔离连续性、路面维护状况越差,划线停车和阻碍也更多。结论 12个城市步行道配备及维护状况差异具有统计学意义,12个城市步行道的配备情况还存在进一步改善的空间。建议在进行城市道路规划时,结合当地人口密度和实际的交通需求,合理配备步行道;同时加强城市管理,减少步行道上的阻碍。