OBJECTIVES: To describe the development of the Oxford WebQ, a web-based 24 h dietary assessment tool developed for repeated administration in large prospective studies; and to report the preliminary assessment of its performance for estimating nutrient intakes. DESIGN: We developed the Oxford WebQ by repeated testing until it was sufficiently comprehensive and easy to use. For the latest version, we compared nutrient intakes from volunteers who completed both the Oxford WebQ and an interviewer-administered 24 h dietary recall on the same day. SETTING: Oxford, UK. SUBJECTS: A total of 116 men and women. RESULTS: The WebQ took a median of 12·5 (interquartile range: 10·8-16·3) min to self-complete and nutrient intakes were estimated automatically. By contrast, the interviewer-administered 24 h dietary recall took 30 min to complete and 30 min to code. Compared with the 24 h dietary recall, the mean Spearman's correlation for the 21 nutrients obtained from the WebQ was 0·6, with the majority between 0·5 and 0·9. The mean differences in intake were less than ±10 % for all nutrients except for carotene and vitamins B12 and D. On rare occasions a food item was reported in only one assessment method, but this was not more frequent or systematically different between the methods. CONCLUSIONS: Compared with an interviewer-based 24 h dietary recall, the WebQ captures similar food items and estimates similar nutrient intakes for a single day's dietary intake. The WebQ is self-administered and nutrients are estimated automatically, providing a low-cost method for measuring dietary intake in large-scale studies.

Original publication

DOI

10.1017/S1368980011000942

Type

Journal article

Journal

Public Health Nutr

Publication Date

11/2011

Volume

14

Pages

1998 - 2005

Keywords

Adult, Aged, Aged, 80 and over, Diet, Diet Records, Dietary Fats, Dietary Proteins, Energy Intake, Female, Great Britain, Humans, Internet, Interviews as Topic, Male, Micronutrients, Middle Aged, Nutrition Assessment, Prospective Studies, Reproducibility of Results, Surveys and Questionnaires, Young Adult