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.

Increasing response to mailed questionnaires by including a pencil/pen.

Nonmonetary incentives lead to small increases in response rates to mailed questionnaires. However, inclusion of a pen or pencil, which may be a facilitating factor as well as a reward, has not been shown to improve response to health surveys in prior trials. In 2001 and 2002, the authors conducted two US trials in which a study-logo pen or pencil was randomly included in a second questionnaire mailed to nonresponders to a first mailing.

A practical method for collecting 3-day food records in a large cohort.

Background: Recent studies suggest that diet records are more valid measures of nutrient intake than are food-frequency questionnaires. However, food records are considered unsuitable for large studies due to the need to train participants and to review and correct completed records.

Methods: We evaluated a self-administered 3-day food record protocol in Washington State.