Evaluation of web-based, self-administered, graphical food frequency questionnaire.
Computer-administered food frequency questionnaires (FFQs) can address limitations inherent in paper questionnaires by allowing very complex skip patterns, portion size estimation based on food pictures, and real-time error checking. We evaluated a web-based FFQ, the Graphical Food Frequency System (GraFFS). Participants completed the GraFFS, six telephone-administered 24-hour dietary recalls over the next 12 weeks, followed by a second GraFFS. Participants were 40 men and 34 women, aged 18 to 69 years, living in the Columbus, OH, area. Intakes of energy, macronutrients, and 17 micronutrients/food components were estimated from the GraFFS and the mean of all recalls. Bias (second GraFFS minus recalls) was -9%, -5%, +4%, and -4% for energy and percentages of energy from fat, carbohydrate, and protein, respectively. De-attenuated, energy-adjusted correlations (intermethod reliability) between the recalls and the second GraFFS for fat, carbohydrate, protein, and alcohol were 0.82, 0.79, 0.67, and 0.90, respectively; for micronutrients/food components the median was 0.61 and ranged from 0.40 for zinc to 0.92 for beta carotene. The correlations between the two administrations of the GraFFS (test-retest reliability) for fat, carbohydrate, protein, and alcohol were 0.60, 0.63, 0.73, and 0.87, respectively; among micronutrients/food components the median was 0.67 and ranged from 0.49 for vitamin B-12 to 0.82 for fiber. The measurement characteristics of the GraFFS were at least as good as those reported for most paper FFQs, and its high intermethod reliability suggests that further development of computer-administered FFQs is warranted.
Alan R
AR
Kristal
Ann S
AS
Kolar
James L
JL
Fisher
Jesse J
JJ
Plascak
Phyllis J
PJ
Stumbo
Rick
R
Weiss
Electra D
ED
Paskett
D000293:Adolescent; D000328:Adult; D000368:Aged; D015930:Diet Records; D004040:Dietary Carbohydrates / Q000008:administration & dosage; D004041:Dietary Fats / Q000008:administration & dosage; D004043:Dietary Fiber / Q000008:administration & dosage; D004044:Dietary Proteins / Q000008:administration & dosage; D002149:Energy Intake; D005260:Female; D006801:Humans; D020407:Internet; D008297:Male; D011939:Mental Recall; D018977:Micronutrients / Q000008:administration & dosage; D008875:Middle Aged; D015596:Nutrition Assessment; D015203:Reproducibility of Results; D012646:Self Administration; D011795:Surveys and Questionnaires; D055815:Young Adult; D019207:beta Carotene / Q000008:administration & dosage
D004040:Dietary Carbohydrates; D004041:Dietary Fats; D004043:Dietary Fiber; D004044:Dietary Proteins; D018977:Micronutrients; D019207:beta Carotene
Computer-administered questionnaires; Dietary assessment; Evaluation; Food frequency questionnaire; Reliability