|Baseline Questionnaire (BQ)||~154,000||1993-2001|
|Dietary Questionnaire I-only (DQX)||~63,000||1993-2001|
|Diet History Questionnaire (DHQ)||~119,000||1998-2004|
|Supplemental Questionnaire (SQX)||~104,000||2006-2007|
|Medical Use Questionnaire (MUQ)||~60,000||2013|
|Brief Survey (BCQ)||~47,000||2017-2018|
|Collection of Cancers|
|Collection of Mortality|
Timeline from T0 to T13 showing the collection of dietary questionnaires (DQX) in the trial. Only the intervention arm completed the DQX at T0. The control arm was not given the DQX.
The Dietary Questionnaire (DQX) was offered to intervention arm participants around the time they were randomized. 82% of the intervention arm completed a DQX. Control arm participants were not offered the DQX. The form may have been completed before (<1%) or after the participant was randomized, but about half (47%) were collected within one month of randomization and most (90%) were collected within three months.
Raw questionnaire responses were processed into analysis-ready variables in terms of gram intake, pyramid servings, food frequencies per day, etc.
DQX data can be obtained in the DQX dataset.