There’s more to food store choice than proximity: a questionnaire development study

Obesity is one of the most pressing public health problems, largely because it is a risk factor for a wide range of chronic diseases [1]. In recent years, efforts to understand the obesity epidemic have focused attention on understanding the role of the “built environment” (i.e., the physical surroundings that can impact dietary intake or energy expenditure, including food stores) [2]. Many experts now agree that the built environment must be considered in efforts to address obesity [3].

In some research, proximity of food stores, specifically supermarkets, has been positively linked with healthful dietary intake [4, 5], and obesity [6‐8], yet in other research, no association or negative associations have been found between the proximity of food stores and dietary intake [9‐12] or obesity [11, 13‐15]. Perhaps helping to explain these inconsistent findings related to food store proximity and diet/ obesity, recent research has found that individuals frequently shop at stores that are not the most proximal [15‐17] and little is known about the reasons which do guide selection of a food store. With the underlying assumptions that food store preferences influence food store choice, and that food store choice then proximally impacts dietary intake and more distally impacts weight status, it is important to understand how individuals select the stores at which they shop in order to design food store interventions that could alter dietary intake and weight status. There have been a few studies in the United States that have utilized short (i.e., five to seven item) measures to understand reasons for food store choice among low-income residents [18, 19] or among Latinas [20]; however, a more comprehensive description of the factors influencing food store choice in a broader sample of individuals has not yet been conducted. In addition, the degree to which the questionnaires used in these studies were developed based on community input is uncertain, so it is unclear as to whether these questionnaires accurately represent the diversity of community perceptions and capture the full range of factors relevant to food store selection.

Obtaining a clear picture of the reasons associated with food store choice has been difficult up to this point because of the lack of a comprehensive measure which gathers information on all of the potentially relevant factors. Thus, the first phase of this study was to develop a descriptive questionnaire regarding the importance of key factors on food store selection which would be appropriate for use in a range of communities. A second phase was to field-test the questionnaire to gather initial information about the relative importance of various factors in food store choice in a diverse group with significant representation of populations at high risk for obesity.

Although there are many measures of the store food environment, one thing that has been missing from the food environment literature has been a comprehensive questionnaire that details the reasons for choosing one’s primary food store. The initial findings from the newly developed and field-tested FSSQ clearly indicate that there are several key factors related to food store choice and the data shed light on the relative importance of various reasons for choosing a food store among participants from diverse backgrounds.

These findings demonstrate important similarities and differences with previous research as to the key factors in food store choice. Several previous studies have demonstrated that isolated factors were relevant to store selection (i.e., safety, food quality, variety of foods, ability to complete shopping quickly, prices, proximity to home/work, store cleanliness, customer service, and store hours) [18‐20]; however, none of the previous studies included all of these key items simultaneously and often distinct items were grouped together in a single question (e.g., “cleanliness and good service” or “it is cheap, has bulk items, and double coupons”). The emergence of some of these factors as among the most important ones identified as driving store choice, on a measure which included all these factors, is one of the main contributions of this research to the field because it demonstrates relative prioritization of the factors. In addition, while there was not an item in the current study specifically focused on cultural or ethnic foods that is directly comparable to the items used by Wang [19] and Ayala [20], the FSSQ has several items including “the store has foods that I grew up eating,” “the store has foods that I know how to prepare,” and “I can buy foods that I eat for religious reasons” that likely tap into a similar construct. In contrast to Wang and Ayala‘s research, none of these items were among the items indicated as most important in the current sample when provided with an extended listing of reasons for selecting a food store.

Because this questionnaire was developed through a multi-stage process that included considerable community involvement, the FSSQ is a more comprehensive measure than previously available. Specifically, several reasons that were cited as among the most important reasons for food store choice (e.g., brands, payment options) have not previously been included in research in this area [18‐20]. In addition, it is a strength of this questionnaire that two different methods (i.e., 1–5 rating of importance, rating of top two reasons) for evaluating factors most important in food store choice are possible because one method may be more appropriate for a particular study than the other method. For example, for a community level-intervention, it may be considered to be more helpful to calculate mean importance of various factors across many individuals and for an individual level-intervention, it may be considered more important to know the reasons perceived by each individual as “top”. Further research to elucidate which approach to asking how food stores are selected is most informative for which populations and which purposes, and to consider whether there is something about incorporating both of the vantage points which can enrich understanding about the decision making processes surround food store selection.

It is important to note that, while proximity to home was an important reason for selecting one’s primary food store, there were several other reasons that were rated as important, if not more important, than proximity to home. Therefore, research that presumes that residents living near a food store will be likely shopping at this location [4‐6] may be problematic. Future research may wish to directly assess the primary food store at which individuals shop and the amount of time that they have shopped at this store when examining the impact of primary food store on dietary intake and obesity, instead of assuming that the most proximal store is the one at which individuals shop.

This study had several strengths and limitations that should be considered when interpreting the results. First, the researchers were successful in recruiting a sample that was diverse in many ways, including race, age, educational background, and rurality. Although the majority of participants were female, it is likely that our sample is representative of primary household food shoppers; however, all of the participants belonged to households with at least two individuals, who did not follow a special diet requiring shopping at one store, and were available and interested in completing the questionnaire. Thus, the findings might not generalize to individuals who only shop for themselves, those with severe dietary restrictions, and those who did not have the time or interest in completing a questionnaire. In addition, despite achieving a sample diverse on several sociodemographic characteristics, all participants for the development and field testing of the questionnaire were from one relatively rural state; thus, the results are likely most generalizable to other rural states. However, the questionnaire was developed with the input of experts living in more urban areas and demonstrated some consistency with previous research in larger metropolitan areas [19, 20] and could well be relevant for populations in more urban areas. Nonetheless, it will be important to examine the factors that are most important in food store choice in other communities (rural and urban). Furthermore, it is important to acknowledge the relatively small sample size in this study. In future research with a larger sample size, it will be interesting to examine whether reasons for choosing a store differ based on sociodemographic characteristics; with this information, it may be possible to tailor a food store intervention to reasons that are important for particular communities or sociodemographic groups. With a larger sample, it would also be possible examine the clustering of items among subgroups of individuals as well as the potential underlying domains of reasons for choosing a food store. Finally, it will be crucial to examine the reliability of the questionnaire in future research.

Upon confirmation of these findings in other communities, knowing the primary reasons why individuals choose a food store may be beneficial in guiding policies and programs in making food environmental changes crafted to support dietary change and obesity prevention. In particular, based on the findings in the current study, future food store interventions may wish to focus on the availability, quality, variety, and prices of fruits, vegetable and meats, rather than a more global focus on more healthful food items (e.g., diet beverages, baked/low-fat chips) as has been done in many food store interventions [25‐28]. Furthermore, our findings indicate that store characteristics including payment options, cleanliness, maintenance, safety, and opening hours of the store will be crucial factors in the potential success of such an intervention. Nonetheless, the sustainability of a healthy store environment will likely be greatly impacted by other factors including macro-level influences (e.g., food and agriculture policies) [29, 30].

RK conceived of the study and obtained funding, and participated in its design and coordination, drafted the manuscript, and performed the quantitative analyses. CS and MD participated in the study’s design and coordination. JM participated in the design of the study. DW conceived of the study and obtained funding, and participated in its design and coordination. All authors read and approved the final manuscript.