Texas nutrition environment assessment of retail food stores (TxNEA-S): development and evaluation

Abstract

Objective: Current nutrition environment instruments are typically designed to measure a small number of healthy foods based on national trends. They lack the depth to accurately measure the unique dietary choices of subpopulations, such as Texas consumers whose food preferences are influenced by Hispanic/Latino culture. Thus the purposes of the present study were to: (i) develop a comprehensive observational tool to measure the availability of healthy foods from retail stores in Texas; and (ii) conduct a pilot test to examine the tool's reliability, as well as differences in the availability of healthy foods in stores between high- and low-income neighbourhoods.

Design: Grocery and convenience stores were assessed for availability of healthy foods. Reliability was calculated using percentage agreement, and differences in availability were examined using 2 (store type) × 2 (neighbourhood income) ANOVA.

Setting: One high-income and one low-income neighbourhood in Austin, Texas.

Subjects: A sample of thirty-eight stores comprising twenty-five convenience stores and thirteen grocery stores.

Results: The low-income neighbourhood had 324 % more convenience stores and 56 % fewer grocery stores than the high-income neighbourhood. High inter-rater (mean = 0·95) and test-retest reliability (mean = 0·92) and a significant interaction (P = 0·028) between store type and neighbourhood income were found.

Conclusions: The TxNEA-S tool includes 106 healthy food items, such as fruits, vegetables, dairy, proteins and grains. The tool is reliable and face validity is affirmed by the Texas Department of Health. Grocery stores have more healthy foods than convenience stores, and high-income grocery stores offer more healthy foods than low-income grocery stores.