| 0 | Patient was not infected (mainly for children) |
| 1 | Patient lost to follow-up / not known to be dead |
| 2 | Patient has not had visit within required amount of time |
| 2.1 | Patient did not respond to several invitations |
| 3 | Patient moved away |
| 3.1 | Patient moved to another country |
| 4 | Patient moved and is followed by another centre |
| 4.1 | Paediatric patient transferred to adult care |
| 5 | Patients decision |
| 5.1 | Patients caretaker wanted to discontinue (for children) |
| 6 | Consent withdrawn |
| 7 | Incarceration/jail |
| 8 | Institutionalisation (drug treatment, psychological …etc.) |
| 9 | Other |