Creating an accurate and informative assessment of the food environment in low-income ethnic communities requires attention to a broad variety of characteristics of the physical, consumer, and social food environments. Although all four settings described here are characterized by a low-income consumer base, the food environments across these settings differ dramatically. In Baltimore, residents generally live within walking distance of some food sources (although usually not supermarkets) and a high proportion of small stores have a closed configuration and do not permit customers inside the stores. Of those that do, some limit access to foods within the stores to regular customers, and do not permit children inside.29
Thus, in this urban setting, retail food sources are close geographically, but access to foods within the store may be limited. This contrasts with the American Indian and First Nations settings, in which stores are generally further from where individuals live, but once one reaches those stores, access to foods is unfettered. In both settings, stores carrying a wide range of nutritious food choices are relatively distant from where people live.
This work indicates that the food environment must in many cases be broadly defined. As discovered in interviews with small store owners in Baltimore, stocking nutritious foods was related directly to their availability in wholesale stores. The assessment of the food environment should include food wholesalers and distributors as well. Use of the USDA commodity food program is common within low-income American Indian communities, but practically non-existent among African Americans in Baltimore. All of the differences mentioned suggest that to truly describe access to and use of food, investigators must expand their descriptions to include the physical settings within which foods are selected, the broad types of food sources (wholesale and retail) and suppliers, and the relationships between store managers and their clientele.
How should investigators proceed when faced with assessing a new and unique food setting? It is possible to modify existing instruments when working in diverse settings, as has been done with the NEMS-S for use in low-income urban areas.32
However, inclusion of all potential physical, consumer and social characteristics are likely beyond the means, and more importantly, the needs of individual studies of the food environment. In our own work, which is centered on changing food availability, food environment assessments have been restricted to assessing the presence of key promoted foods (more nutritious alternatives to high-fat, high-sugar foods commonly consumed, and at the same or lower price), as well as on features of local food sources that are likely to impinge or enhance access to these foods (e.g., closed food store layouts in Baltimore). The emphasis on data-gathering for the purpose of monitoring and evaluating the success of food source interventions allowed us to focus the environmental assessments. We recommend that investigators developing environmental assessment tools conduct formative research that will enable them to develop focused instruments that incorporate those physical, consumer and social characteristics of their setting that are relevant to their research purposes.