Feasibility Study of a Web-Based Automated Self-Administered 24-hour Dietary Recall (ASA 24) and a Physical Activity 24-hour Recall

In spite of long-standing hypothesis relating diet and physical activity to several cancers,
diet and physical activity-cancer associations have been modest at best and often
inconsistent in epidemiologic studies. Investigators around the world have become
increasingly concerned that error in the measurement of both diet and physical activity is
compromising our ability to detect these important but modest associations. Most commonly
used diet and physical activity assessment methods have been based on a relatively small set
of questions (e.g. 124 food items consumed or 5-10 physical activities in the past 12
months). Recent developments in computer technology provide an opportunity to use
internet-based instruments to assess an individual s diet and physical activity more
accurately and cost effectively.

NCI has been developing two web-based instruments, an automated self-administered 24-hour
dietary recall (ASA24) and a physical activity 24-hour recall (ACT24), which can be
administered several times over a year. Although these two instruments have the potential to
qualitatively improve exposure assessment (at relatively low cost), they need to be evaluated
for feasibility before being incorporated in cohorts on a large scale. Therefore, we propose
to test ASA24 and ACT24 among AARP members aged 50 years and over to evaluate technical
problems, determine response rates, and estimate the range of dietary intake and physical
activity. In addition, we propose to include in this feasibility study two web-based versions
of conventional questionnaires (lifestyle and medical history questionnaire and diet history
questionnaire) as well as two software systems needed to conduct a web-based study (the
automated Study Management System and Web Survey Management System). We will initially target
15,000 AARP members, expecting that approximately 2,000 individuals will agree to participate
in the study and about 1,250 participants will complete ASA24 and ACT24 twice.

These web-based instruments and accompanying system tools represent a novel approach to
carrying out diet and lifestyle research. The computerized, web-based study method can be
applied to any observational study, large or small, case-control or cohort, as well as
randomized controlled trials. This feasibility study will provide an opportunity to assess
the feasibility of constructing large web-based cohort studies and characterize potential
participants.

- We will recruit 5,000 subjects from the existing NIH-AARP study participants who are
currently 62 to 83 years old. To include individuals who are at least 50 years old, we
will expand our recruitment effort to 10,000 new AARP members who are at least 50
years old and not currently NIH-AARP study cohort members. We will target individuals
residing in one of the following states: Florida; Pennsylvania; New Jersey; Louisiana;
North Carolina; California; Detroit; Michigan; and Atlanta, Georgia, Nevada, Arizona,
Texas, Illinois, Washington, Wisconsin, Colorado, Connecticut, Kentucky, Utah and
Massachusetts (subject to change due to availability of high-quality state cancer
registries). The names and addresses of new AARP members will be provided by AARP.