Adult and elderly Lifelines participants participating in second assessment 2A received two questionnaires, 2A Questionnaire 1 and 2A Questionnaire 2.
2A Q1 was followed by 2A Visit 1, on average within xx days (+/- yy days).
2A Q1 was also followed by 2A Questionnaire 2, on average within xx weeks (+/- yy weeks).
2A Q1 was followed up by assessment 2B, on average within xx months (+/1 yy months).
2A Q1 is procedurally equivalent to 1A Questionnaire 1 and 3A Questionnaire 1.
The average time between 1A Questionnaire 1 and 2A Q1 was xx months (+/- yy months).

N=xxx participants filled in a paper variant of 2A Q1, N=yyy participants filled in a digital variant of 2A Q1.

2A Q1 contained the following sections and subsections:

• Personal data
• Family composition
• Profession (self-reported)

• Allergies
• Chronic Fatigue Syndrom (CDC)
• Eye Conditions
• Fatigue (general)
• Musculoskeletal symptoms
• Pain (WPI)
• Respiratory problems (ELON)
• Symptoms (SCL-90)

• Independence

• Drug use
• Home environment (general)
• Informal care
• Physical activity (SQUASH)
• Smoking & tobacco use

• Hospitalization
• Medication
• Surgery
• Treatment (general)

• Quality of Life (RAND)
• Stress (LDI)
• Stress (LTE)

NB: The three FFQ petals (A/B/C) were distributed over three questionnaires (1B, 1C and 2A Q1), so that each participant received the petals in one of six possible orders (ABC, ACB, BAC, BCA, CAB, or CBA).

• Macronutrients (FFQ-h)
• Petal A (FFQ-a)
• Petal B (FFQ-b)
• Petal C (FFQ-c)

• Anthropometry (self-reported)