Food environments are relevant to recruitment and adherence in dietary modification trials

Abstract

Few studies have examined the built environment's role in recruitment to and adherence in dietary intervention trials. Using data from a randomized dietary modification trial of urban Latina breast cancer survivors, we tested the hypotheses that neighborhood produce access could act as a potential barrier and/or facilitator to recruitment, and that a participant's produce availability would be associated with increased fruit/vegetable intake, one of the intervention's targets. Eligible women who lived within a higher produce environment had a non-significant trend towards being more likely to enroll in the trial. Among enrollees, women who had better neighborhood access to produce had a non-significant trend toward increasing fruit/vegetable consumption. As these were not a priori hypotheses to test, we consider these analyses to be hypothesis generating and not confirmatory. Results suggest that participants' food environment should be considered when recruiting to and assessing the adherence of dietary intervention studies.

Keywords: Breast cancer; Dietary interventions; Food environments; Geographic Information Systems (GIS); Nutrition.

Copyright © 2015. Published by Elsevier Inc.

Figures

Figure 1. Density of Produce in New York City Per Square Kilometer

Map of the produce outlets per square kilometer in New York City relative to the homes of the patient population as well as the Columbia University Medical Center and Columbia University Teacher's College Test Kitchen. Each circle represents a .5 kilometer buffer around each eligible woman's residence. We used ArcGIS Spatial Analyst (ESRI,Redlands, CA) to estimate a continuous surface of produce outlets with a kernel function using a one mile bandwidth.