National registration number | Pseudonymisation | Pseudonymised code |
Principal and secondary diagnosis of a complex chronic condition | Principal diagnosis aggregated to 1 of the 9 categories; secondary diagnosis aggregated to 1 of the 9 categories | Cancer; digestive disease; cardiovascular disease; haematological/immunological disease; neurological disease; respiratory disease; urinary disease; congenital/genetic disease; metabolic disease |
Dates of admission to and discharge from hospital | Day/month/year | Day/month/year of admission day/month/year of discharge |
Date of birth (day/month/year) | Aggregated to six categories | 0–11 months, 1–4 years, 5–9 years, 10–15 years, 16–19 years, >20 years |
Gender | Male/female/unknown/changed | Male/female |
Postal code of residence | Aggregated to one of the 13 regions in Belgium | 13 regions in Belgium; unknown |
Nationality | Aggregated to one of the six regions defined by WHO | 6 regions |
Insurance status | Insured or not | Insured or not |