Fruit & Vegetable Screeners in the Eating at America's Table Study (EATS): Overview
In the early 1990s, RFMMB staff worked with individual grantees to the
National Cancer Institute's 5 A Day for Better
Health Program to develop a short 7-item assessment tool to measure intake
of fruits and vegetables (Thompson, FE and Byers, T. Dietary Assessment
Resource Manual. J Nutr 1994;124(11S):2305S). This tool has been used
widely to track changes in fruit and vegetable intake in specific population
groups.
Because fruits and vegetables seemed to be underreported using this tool,
staff developed a new short assessment form in 1996. This form asked about
consumption of fruits and vegetables other than salad and potatoes by time of
day (morning, midday/afternoon, evening), while continuing to ask about the
usual daily consumption of fruit juice, salad, and potatoes overall without
reference to time of day. The performance of the new screener was compared to
the performance of the 5 A Day screener. Both screeners produced large
underestimates of total fruit and vegetable intake, as assessed by the 24-hour
recalls, analyzed within a measurement error model. The new by-meal screener
performed somewhat better, however. (See Thompson
FE et al. Evaluation of 2 brief
instruments and a food-frequency questionnaire to estimate daily number of
servings of fruit and vegetables. Am J Clin Nutr
2000;71:1503-10.)
In 1998, cognitive interviews of about 30 men and women were conducted to
refine the wording of specific food categories, portion size questions, and time
frame issues (all day vs. by meal). These findings were incorporated into two
versions of new screeners. Both of these screeners feature:
- more precise wording of foods asked;
- an additional question
about dried beans;
- three additional questions about vegetable
mixtures; and
- portion size questions for every food item.
Both new versions contain the same food item description and portion size
ranges; they differ in that one asks about usual intakes of all items (termed
the All-Day version), and the other asks about usual intakes of fruits and other
vegetables by time of day (termed the By-Meal version). Both are machine
scannable. In one timed test, the By-Meal screener took an average of 14
minutes to complete.
The performance of each new screener was evaluated in the Eating at America's Table Study (EATS). A sample of
462 adult men and women, living throughout the US, completed one of the two
screeners and four 24-hour recalls, 1 per season, taken over a year's time.
Fruit and vegetable intake estimated from each screener were compared to the
24-hour recalls using a measurement error model (see Thompson
FE et al. Fruit and vegetable assessment:
performance of 2 new short instruments and a food frequency questionnaire. J
Am Diet Assoc 2002;102(12):1764-72).
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