Adult and elderly Lifelines participants participating in general assessment 1A (“Baseline”) received two follow-up questionnaires, 1B and 1C.
1C was sent out on average 28 months (SD ± 10 months) after 1A Questionnaire 2.
1C was sent out on average 12 months (SD ± 3 months) after 1B.
1C was followed by 2A Questionnaire 1 after on average 16 months (± 10 months).
Of all participants that filled out 1C (n = ~100,000), 33% of participants filled in a paper variant whereas 66% filled in a digital variant.
1C contained the following sections and subsections:
NB: Only elderly participants (65+) were asked these questions
NB: The three FFQ petals (1/2/3) were distributed over three questionnaires (1B, 1C and 2A Questionnaire 1), so that each participant received the petals in one of six possible orders ([1-2-3], [1-3-2], [2-1-3], [2-3-1], [3-1-2], or [3-2-1]).