Defining Measures (Instruments and Methodologies)

The measures of the food environment can be classified as either instruments or methodologies.

Instruments

An instrument may take the form of a checklist, inventory, market basket, or interview/questionnaire. Instruments are standardized assessment tools; typically they are paper-based forms completed by subjects themselves or by trained observers. The instruments can be tested for relevant psychometric properties (e.g. reliability and validity), applied to different types of food environments, and modified as needed for specific populations.

• Checklist: a pre-defined list of indicator foods which are selected based on predetermined criteria, such as those foods that are identified by the researchers as aligning with current dietary guidance. A checklist may be used in food stores, restaurants, schools, or worksites.
• Inventory: a form for recording all foods available in a given environment An inventory may be used in food stores, restaurants, schools, or worksites.
• Market basket: a pre-defined list of foods that represent a range of food choices across a total diet. These foods may be based on foods frequently consumed by the population or may reflect a standardized diet plan like the U.S. Department of Agriculture's Thrifty Food Plan. A market basket is usually used in food stores.
• Interview/questionnaire: a pre-determined list of questions that is administered by a trained interviewer or completed by the respondent via self-report. An interview/questionnaire may be used in food stores, restaurants, schools, or worksites.

Methodologies

Methodologies include geographic analysis, menu analysis, nutrient analysis, and sales analysis.

• Geographic analysis: draws data from specific geographic measures; this includes counts of the number of food stores or restaurants within a specific area; the nearest distance to food stores or restaurants; and/or the food type, price, and quality available in food stores or at restaurants within a specific area.
• Menu analysis: uses information on a menu as the basis for data collection and evaluation.
• Nutrient analysis: uses nutrient data such as saturated fat, energy, and sodium to evaluate foods available for school lunches, as à la carte foods, and in vending machines.
• Sales analysis: uses data from sales, cashier receipts, and food service reporting forms to determine availability and patterns of purchase for certain foods (e.g., fruits and vegetables).