Location: Children's Nutrition Research CenterTitle: The utility of Geographical Information Systems (GIS) in systems-oriented obesity intervention projects: The selection of comparable study sites for a quasi-experimental intervention design--TX CORD Author
|Oluyomi, Abiodun - University Of Texas|
|Byars, Allison - University Of Texas|
|Byrd-williams, Courtney - University Of Texas|
|Sharma, Shreela - University Of Texas|
|Durand, Casey - University Of Texas|
|Hoelscher, Deanna - University Of Texas|
|Butte, Nancy - Children'S Nutrition Research Center (CNRC)|
|Kelder, Steven - University Of Texas|
Submitted to: Childhood Obesity
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/1/2014
Publication Date: 2/1/2015
Citation: Oluyomi, A.O., Byars, A., Byrd-Williams, C., Sharma, S.V., Durand, C., Hoelscher, D.M., Butte, N.F., Kelder, S.H. 2015. The utility of Geographical Information Systems (GIS) in systems-oriented obesity intervention projects: The selection of comparable study sites for a quasi-experimental intervention design--TX CORD. Childhood Obesity. 11(1):58-70.
Interpretive Summary: Texas Childhood Obesity Research Demonstration project (TX CORD) was implemented in intervention and comparison catchment areas in Austin and Houston. In order to select and compare the intervention and comparison study sites, a Geographical Information System (GIS) methodology based on census data, school data, and demographic data collected from study participants were used. The selection process resulted in the targeted population composition and intervention and comparison catchment areas were comparable. Our findings are important and aid researchers on potential analytical procedures in community health research and offer significant contributions in terms of community assessment and engagement.
Technical Abstract: The Texas Childhood Obesity Research Demonstration project (TX CORD) uses a systems-oriented approach to address obesity that includes individual and family interventions, community-level action, as well as environmental and policy initiatives. Given that randomization is seldom possible in community-level intervention studies, TX CORD uses a quasi-experimental design. Comparable intervention and comparison study sites are needed to address internal validity bias. TX CORD was designed to be implemented in low-income, ethnically diverse communities in Austin and Houston, Texas. A three-stage Geographical Information System (GIS) methodology was used to establish and ascertain the comparability of the intervention and comparison study sites. Census tract(stage 1) and school(stage 2) data were used to identify spatially exclusive geographic areas that were comparable. In stage 3, study sites were compared on demographic characteristics, socioeconomic status (SES), food assets, and physical activity (PA) assets. Student's t-test was used to examine significant differences between the selected sites. The methodology that was used resulted in the selection of catchment areas with demographic and socioeconomic characteristics that fit the target population: ethnically diverse population; lower-median household income; and lower home ownership rates. Additionally, the intervention and comparison sites were statistically comparable on demographic and SES variables, as well as food assets and PA assets. This GIS approach can provide researchers, program evaluators, and policy makers with useful tools for both research and practice. Area-level information that allows for robust understanding of communities can enhance analytical procedures in community health research and offer significant contributions in terms of community assessment and engagement.