Which data do we collect?

All medical data are separately stored from the registration data under a unique code number in our database. They are therefore not directly traceable to you as a person. Read more about this subject under Datacollection: How is my data protected.

Current overview of data collection (in Dutch)

Demographic and geographic information: relevant demographic and geographic data such as date of birth, country of birth and nationality.

Diagnosis and referral: information about where the first positive HIV test was carried out and who made the referral to an HIV treatment centre.

HIV tests: data about previous negative and positive HIV tests.

Time of HIV acquisition and symptoms: information about the suspected moment of HIV acquisition and symptoms that may have been associated with the HIV infection.

Stage of HIV infection: information about whether the HIV infection was acute or chronic at the time of diagnosis.

Transmission: relevant data relating to acquisition of HIV, including the most likely route of transmission.

Medical history: information about relevant medical conditions in the past, including hepatitis A or B infection, malignancies, fractures, etc.

PrEP use: data about PrEP use, such as which medicines were used and how were they taken (i.e., according to which schedule).

Visits and measurements: all visits to a healthcare provider, including data about heigth, weight, BMI and blood pressure.

Substance use: the use of substances that may influence the treatment outcome, such as alcohol, medicines, or drugs, and smoking.

Vaccinations: information about any vaccinations against hepatitis A, hepatitis B, HPV, COVID-19, pneumococci and varicella zoster.

HIV-related conditions: we document the presence of conditions that may be related to the HIV infection, such as opportunistic infections and certain malignancies.

Other medical conditions: we also document the presence of other relevant conditions, such as cardiovascular disease, malignancies, liver disease and COVID-19.

Antiretroviral therapy:  Medication prescribed to treat the HIV infection (and/or an HBV co-infection), includingthe doses, the start date and date of discontinuation, as well as reasons for discontinuing.

This includes other medicines that are not part of the HIV treatment, including both the start and discontinuation dates.

Laboratory test results

  • HIV diagnostic work-up: tests to detect the presence of HIV virus particles (viral load) and antibodies to the virus.
  • Virology and serology: tests to detect the presence of pathogenic virusses, antigens (proteins of specific micro-organisms), and antibodies in blood samples. 
  • Immunology: tests to investigate the immune response.
  • Haematology: tests relating to the blood and blood-forming tissue.
  • Clinical chemistry: tests to detect the presence of certain molecules such as proteins or hormones. 
  • Sexually-transmitted infections: tests to detect the presence of sexually transmitted infections. 
  • Antiretroviral therapy concentrations: tests to detect the presence of HIV medication in the blood.
  • Other pathogens: tests to detect the presence of other pathogens, such as other viruses or parasites.  
  • Additional provisions for COVID-19

Liver work-up

  • Fibroscan (liver elastography): date and outcome of fibroscan (elastography) test.
  • Liver biopsy: date and results of liver biopsy. 
  • Liver radiology: date of exam and results of, e.g., ultrasound, CT or MRI scan of liver.

Anal or cervical exam: date of exam and results of, for example, an anal or cervical biopsy or smear test. 

Bone density exam: date of exam and results of, for example, X-ray images or dexascan.


Relevant data relating to periods of hospitalisation, such as dates of admission and discharge, and reason for admission.  

Viral hepatitis: relevant data about an infection with hepatitis A,  B, C or D, such as start and end dates, symptoms and route of transmission.

Information about the pregnancy, delivery, and certain relevant birth-related information about the infant (limited to information contained in mother's medical records), such as duration of pregnancy and measures taken to prevent an HIV infection in the infant.