Computerized portion-size estimation compared to multiple 24-hour dietary recalls for measurement of fat, fruit, and vegetable intake in overweight adults

Validated self-report methods of dietary assessment exist and might be improved in terms of both accuracy and cost-efficiency with computer technology. The objectives of this preliminary study were to develop an initial version of an interactive CD-ROM program to estimate fruit, vegetable, and fat intake, and to compare it to multiple 24-hour dietary recalls (averaged over 3 days). In 2009, overweight male and female adults (n=205) from Lane County, OR, completed computerized and paper versions of fruit, vegetable, and fat screening instruments, and multiple 24-hour dietary recalls. Summary scores from the 10-item National Cancer Institute Fruit and Vegetable Scan and the 18-item Block Fat Screener were compared to multiple 24-hour dietary recall−derived fruit/vegetable and fat intake estimates (criterion measures). Measurement models were used to derive deattenuated correlations with multiple 24-hour dietary recalls of paper and CD-ROM administrations of Fruit and Vegetable Scan fruit intake, vegetable intake, and fruit and vegetable intake, and Block Fat Screener fat intake. The computerized assessment and paper surveys were related to multiple 24-hour dietary recall−derived fruit/vegetable and fat intake. Deattenuated correlation coefficients ranged from 0.50 to 0.73 (all P≤0.0001). The CD-ROM−derived estimate of fruit intake was more closely associated with 24-hour dietary recall (r=0.73) than the paper-derived estimate (r=0.54; P<0.05), but the other comparisons did not differ significantly. Findings from this preliminary study with overweight adults indicate the need for additional enhancements to the CD-ROM assessment and more extensive validation studies.