Validity of secondary retail food outlet data: a systematic review.
BACKGROUND
Improving access to healthy foods is a promising strategy to prevent nutrition-related chronic diseases. To characterize retail food environments and identify areas with limited retail access, researchers, government programs, and community advocates have primarily used secondary retail food outlet data sources (e.g., InfoUSA or government food registries). To advance the state of the science on measuring retail food environments, this systematic review examined the evidence for validity reported for secondary retail food outlet data sources for characterizing retail food environments.


METHODS
A literature search was conducted through December 31, 2012, to identify peer-reviewed published literature that compared secondary retail food outlet data sources to primary data sources (i.e., field observations) for accuracy of identifying the type and location of retail food outlets. Data were analyzed in 2013.


RESULTS
Nineteen studies met the inclusion criteria. The evidence for validity reported varied by secondary data sources examined, primary data-gathering approaches, retail food outlets examined, and geographic and sociodemographic characteristics. More than half of the studies (53%) did not report evidence for validity by type of food outlet examined and by a particular secondary data source.


CONCLUSIONS
Researchers should strive to gather primary data but if relying on secondary data sources, InfoUSA and government food registries had higher levels of agreement than reported by other secondary data sources and may provide sufficient accuracy for exploring these associations in large study areas.
Division of Nutrition Research Coordination (Fleischhacker), National Institute of Diabetes and Digestive and Kidney Diseases of NIH, Bethesda, Maryland. Electronic address: sheila.fleischhacker@nih.gov.
Sheila E
SE
Fleischhacker
Kelly R
KR
Evenson
Joseph
J
Sharkey
Stephanie B Jilcott
SB
Pitts
Daniel A
DA
Rodriguez
D003132:Commerce / Q000706:statistics & numerical data*; D003625:Data Collection / Q000379:methods*; D057140:Fast Foods / Q000706:statistics & numerical data; D005523:Food Supply / Q000706:statistics & numerical data*; D058870:Food, Organic / Q000706:statistics & numerical data; D006801:Humans; D012111:Residence Characteristics / Q000706:statistics & numerical data; D012147:Restaurants / Q000706:statistics & numerical data; D012959:Socioeconomic Factors