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Weight and Veterans' Environments Study (WAVES) I and II: Rationale, Methods, and Cohort Characteristics
Shannon N Zenk1, Elizabeth Tarlov1,2, Lisa M Powell3,4
11 Department of Health Systems Science, University of Illinois at Chicago College of Nursing, Chicago, IL, USA.
Purpose:
To present the rationale, methods, and cohort characteristics for 2 complementary "big data" studies of residential environment contributions to body weight, metabolic risk, and weight management program participation and effectiveness.
Design:
Retrospective cohort.
Setting:
Continental United States.
Participants:
A total of 3 261 115 veterans who received Department of Veterans Affairs (VA) health care in 2009 to 2014, including 169 910 weight management program participants and a propensity score-derived comparison group.
Intervention:
The VA MOVE! weight management program, an evidence-based lifestyle intervention.
Measures:
Body mass index, metabolic risk measures, and MOVE! participation; residential environmental attributes (eg, food outlet availability and walkability); and MOVE! program characteristics.
Analysis:
Descriptive statistics presented on cohort characteristics and environments where they live.
Results:
Forty-four percent of men and 42.8% of women were obese, whereas 4.9% of men and 9.9% of women engaged in MOVE!. About half of the cohort had at least 1 supermarket within 1 mile of their home, whereas they averaged close to 4 convenience stores (3.6 for men, 3.9 for women) and 8 fast-food restaurants (7.9 for men, 8.2 for women). Forty-one percent of men and 38.6% of women did not have a park, and 35.5% of men and 31.3% of women did not have a commercial fitness facility within 1 mile.
Conclusion:
Drawing on a large nationwide cohort residing in diverse environments, these studies are poised to significantly inform policy and weight management program design.
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