All Lifelines participants of 8 years and older participating in general assessment 2A visited a location of their choice. A trained physician's assistant performed the described measurements, according to the Standard Operating Procedure below.

• NB: In case of temporary counter indications or technical/logistic problems, tests could be rescheduled for 2A Visit 2.
  

• Total duration: 20 minutes + (unassisted) computer tests
• Retrieve the participant from the waiting room
• Check / update basic personal information
• Check if all instruments are ready for use
• Perform the following measurements in order according to their respective SOP’s:
  1. Anthropometry
  2. Blood pressure
  3. ECG
  4. Pulmonary function test (performed only in the first 32,000 adult participants)
  5. Jump test
  6. DAG3-related actions (additional assessment performed in ~9,000 adult participants)
• Instruct participants to do two additional measurements on a computer, unsupervised:
  1. The MINI neuropsychiatric interview, digital self-report version
  2. The CogState test
• Possible changes in the order:
  • Blood pressure and ECG may be swapped

• Total duration: 20 min (plus 10 minutes for on-site 2A Youth Questionnaire)
• Retrieve the child and its parent(s) from the (child-friendly) waiting room
• Check basic personal information
• Check if all instruments are ready for use
• Perform the following measurements in order according to their respective SOP’s:
  1. Anthropometry
  2. Blood pressure
  3. Jump Test
  4. DAG3-related actions (additional assessment performed in ~700 children)
• Instruct older children (13+) to do two additional assessments on a computer, unsupervised:
  1. The 2A Youth Questionnaire, digital self-report
  2. The CogState test

2A Visit 1 was accompanied by 2A Questionnaire 1 which was filled in, on average, 34 days (SD: ± 43 days) prior to visit 1.
2A Visit 1 was followed by 2A Visit 2 within, on average, 40 days.

2A Visit 1 is procedurally equivalent to 1A Visit 1 and 3A Visit 1. The average time between 1A Visit 1 and 2A Visit 1 was 3 years and 11 months.