Background: Although diet is considered one of the major environmental risk factors related to chronic disease, many studies do not evaluate it not only because of practical and logistical issues, but also because of persistent concerns about error in self-reported diet. Web-based tools, however, make it feasible and affordable to collect high-quality, detailed dietary data in large observational studies. The Automated Self-Administered 24-hour recall (ASA24) is an easy-to-use, engaging, self-administered web-based dietary assessment tool. It is freely available from the National Cancer Institute and is available on all mobile devices. Studies can use ASA24 to collect single or multiday 24-hr recalls or food records. ASA24 automatically analyzes reported food, beverage, and dietary supplements intake, generating detailed data files of nutrients and food groups consumed at the person and food/beverage/supplement item level. The ASA24 System includes a researcher website where investigators register to use ASA24, schedule and track participant activities, and obtain data files. Self-reported diet using ASA24 was evaluated against recovery biomarkers (i.e., true intake) in the Interactive Diet and Activity Tracking in AARP (IDATA) Study. Absolute dietary intakes assessed by multiday ASA24 recalls were close to true intakes and outperformed a food frequency questionnaire (FFQ).

Aim: To assess the feasibility of using ASA24 (version 2011) in free living adults 50-74 years old.

Method: Over a 12-month period, men (n=530) and women (n=545) were contacted by email, every other month, to complete an ASA24-2011 (total, 6 ASA24s/year). If a participant did not complete ASA24 after the first contact, a reminder email was sent on a new randomly selected day. Up to three email notifications were sent to obtain each of six ASA24s. Participants also completed a web-based FFQ at months 1 and 12.

Results: Most men (92%) and women (87%) completed at least three ASA24s. 77% of participants completed at least five ASA24s. Completion rate for the 1st FFQ was 81% in men and 73% in women, dropping to 73% and 70%, respectively, for the 2nd FFQ. Most participants (men: 75%; women: 70%) completed ASA24 after the 1st email notification. Another 18% of men and 21% of women completed ASA24 after the 2nd email notification. Median time to complete ASA24-2011 for the 1st administration was 55 minutes in men and 58 minutes in women but declined to about 44 minutes by the 3rd ASA24. Participants <60 years old had a shorter time to complete an ASA24 than those >60 years old. A decline in completion time with each subsequent ASA24 did not appear to affect the quality of diet reporting as there were no systematic decreases in reported energy and nutrient intakes across ASA24 administrations.

Conclusion: It is feasible to collect high-quality diet data using multiday ASAS24s in longitudinal observational studies. New as well as ongoing epidemiologic studies should consider incorporating a detailed dietary assessment such as ASA24 in future studies.

This abstract is also being presented as Poster A35.

Citation Format: Yikyung Park, Kevin W. Dodd, Douglas Midthune, Victor Kipnis, Heather Bowles, Amy F. Subar. Feasibility of assessing individual’s diet using a web-based dietary assessment tool, ASA24, in a longitudinal observational study [abstract]. In: Proceedings of the AACR Special Conference on Modernizing Population Sciences in the Digital Age; 2019 Feb 19-22; San Diego, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2020;29(9 Suppl):Abstract nr PR04.