Lifelines participants participating in general assessment 1A (“Baseline”) visited a location of their choice for a second time, after 1A Visit 1.
At the location, they underwent the following procedures:

• Fasting venapuncture to collect blood samples for blood analyses and blood samples storage (8+ years old).
• Handing in of urine samples for urine analyses and urine samples storage (8+ years old).

Note that for a minority of participants, measurements from the 1A Visit 1 protocol were performed during 1A Visit 2 for medical/logistical/technical reasons.
1A Visit 2 was accompanied by 1A Questionnaire 2 which was filled in, on average, 7 days (SD: ± 25 days) prior to 1A visit 2.
1A Visit 2 was the final part of the Baseline assessment.

1A Visit 2 is procedurally equivalent to 2A Visit 2 and 3A Visit 2. The average time between 1A Visit 2 and 2A Visit 2 was 4 years.