Abstract
Citation
Frank LD, Schmid TL, Sallis JF, Chapman J, Saelens BE. Linking objectively measured physical activity with objectively measured urban form: findings from SMARTRAQ. Am J Prev Med 2005 Feb;28(2 Suppl 2):117-25.
Abstract
BACKGROUND: To date, nearly all research on physical activity and the built environment is based on self-reported physical activity and perceived assessment of the built environment. OBJECTIVE: To assess how objectively measured levels of physical activity are related with objectively measured aspects of the physical environment around each participant's home while controlling for sociodemographic covariates. METHODS: Objective measures of the built environment unique to each household's physical location were developed within a geographic information system to assess land-use mix, residential density, and street connectivity. These measures were then combined into a walkability index. Accelerometers were deployed over a 2-day period to capture objective levels of physical activity in 357 adults. RESULTS: Measures of land-use mix, residential density, and intersection density were positively related with number of minutes of moderate physical activity per day. A combined walkability index of these urban form factors was significant (p =0.002) and explained additional variation in the number of minutes of moderate activity per day over sociodemographic covariates. Thirty-seven percent of individuals in the highest walkability index quartile met the > or =30 minutes of physical activity recommended, compared to only 18% of individuals in the lowest walkability quartile. Individuals in the highest walkability quartile were 2.4 times more likely (confidence interval=1.18-4.88) than individuals in the lowest walkability quartile to meet the recommended > or =30 minutes of moderate physical activity per day. CONCLUSIONS: This research supports the hypothesis that community design is significantly associated with moderate levels of physical activity. These results support the rationale for the development of policy that promotes increased levels of land-use mix, street connectivity, and residential density as interventions that can have lasting public health benefits.
Full Text
The full text is available at https://dx.doi.org/10.1016/j.amepre.2004.11.001
At A Glance
Physical Activity Environment Variables
| # | Type of Environment/Location |
|---|---|
| 357 | Total Environments/Locations |
| # | Scale |
|---|---|
| 357 | 1-km network buffer |
| Measure | objective | perceived |
|---|---|---|
| Street Connectivity | ✔ | ✘ |
| Land Use | ✔ | ✘ |
| Population/Housing Density | ✔ | ✘ |
Domain(s)
Physical Activity Environment
Measure Type
GIS protocol/detailed description
Measure Availability
Measure included in article
Number of Items
Not applicable
Study location
Metro/Urban
Atlanta, GA, USA
Languages
Not applicable
Information about Development of Measure
Different weightings of the land use mix metric were attempted to constitute the walkability index (by related to the physical activity measure)
Study Design
Study Participants
Age
Adults
Sex
Female
Male
Race/Ethnicity
White
Black/African American
Predominantly Low-income/Low-SES
No
Sample Size
357
Study Design
Design Type
Validation/Reliability
Health Outcomes Assessed
Physical activity/inactivity
Obesity Measures
Not applicable
BMI Measured or Self-reported
Not applicable
Covariates
Sociodemographic characteristics (socioeconomic status, race)
Data Reported on Race/Ethnicity
Quantitative data on study sample
Data Reported on SES
Quantitative data on study sample
SES-related Variables
Income
Education
How To Use
Administration
Who Administered
Existing data (e.g., GIS, licensing)
How Administered
Not applicable
Time Required
Not applicable
Training Required
Not applicable
Instructions on Use
Instructions on instrument use included in article
Data Analysis
Data Collection/Analysis Costs
Not available
Data Collection/Protocol
Not available
Instructions on Data Analysis
Instructions on analysis included in article
Validity (3)
| Type of validity | Construct/subscale assessed | Criterion measure used | Test/statistic used | Result |
|---|---|---|---|---|
| Predictive | Walkability Index Quartile 2 | Minutes of Physical Activity measured by Accelerometer | Beta (SE) Odds Ratio (95% CI) | ? = 0.49 (0.37), p=0.19 1.63 (0.79-0.38) |
| Predictive | Walkability Index Quartile 3 | Minutes of Physical Activity measured by Accelerometer | Beta (SE) Odds Ratio (95% CI) | ? = 0.70 (0.37), p=0.055, 2.02 (0.99-4.12) |
| Predictive | Walkability Index Quartile 4 | Minutes of Physical Activity measured by Accelerometer | Beta (SE) Odds Ratio (95% CI) | ? = 0.88 (0.36), p=0.015, 2.40 (1.18-4.88) |
Reliability (0)
There are no reliability tests reported for this measure.