Improving Food Survey Methods
By Rosalie Marion
Bliss September 11, 2008
A study that provides an important indicator of the accuracy of
the latest innovations in food consumption survey methods has been published by
Agricultural Research Service (ARS)
scientists in Beltsville, Md.
During dietary surveys, people are asked to report which foods--and
how much of those foods--they have eaten. When people answer, some may actually
have consumed more or less food than they were able to recall. This is a key
concern to ARS scientists who develop and oversee the ongoing national food
intake survey, What We Eat In
Researchers at the ARS
Surveys Research Group (FSRG) headed by nutritionist
Moshfegh developed a computer-assisted dietary recall method called the
Automated Multiple-Pass Method, or AMPM for short. The method involves a
five-step interview process used to inquire about all eating occasions and all
foods consumed during the previous 24-hour eating period.
The study, involving more than 500 male and female volunteers, was
conducted to test the accuracy of the AMPM. Researchers used what's called the
doubly labeled water technique to measure total energy expenditure--the current
"gold standard" for measuring actual calories burned. This measurement was used
to compare actual calories burned to calorie intakes estimated from three
dietary interviews using the AMPM.
This study confirmed the effectiveness of the AMPM. Research findings
show the method enabled the volunteers to recall what they'd eaten to within 11
percent of the actual calories they used as a sample group.
Among volunteers who were classified as normal weight, the ability to
recall total calories eaten was highly accurate, to within less than 3 percent
of the actual calories used on a group basis.
The scientists noted that more research is needed to enhance the
accuracy of methods for surveying food consumption among overweight and obese
FSRG is part of the ARS
Human Nutrition Research Center.
The study was published in the August issue of the
Journal of Clinical Nutrition.
ARS is a scientific research agency of the
U.S. Department of Agriculture.