Retrospective studies use only data that are already available in the medical record or in a database and do not in any way obtain new data relating to a patient or study participant. All data should be available at the time of (expected) EC submission.

Compile the file


The following are mandatory for a valid application

It is mandatory to use the protocol template for retrospective studies in which UZ Leuven is sponsor. You can find this template on the website of the CTC. 

In case the template is not used, the study will not be valid for EC. 


If relevant for your study, the following components also need to be submitted: 

Prepare the file

Only one file per component can be uploaded.

Do you have several files per component? Group them in a compressed folder (zip file).

Submit the file

If UZ/KU Leuven is the sponsor of the study and only UZ/KU Leuven data will be used in the study without the involvement of a third party, (monocentric study) you should submit the study using the link below. The study will go directly to EC Research and no validation from CTC will be required.

If a retrospective study originates outside of UZ/KU Leuven and involves a third party (multicenter study), it must undergo validation by the Clinical Trial Center (CTC) before it can be submitted to EC Research. You can register your study with the CTC using the registration form. Upon validation by the CTC, you can proceed to submit your study to EC Research via the link provided below.

Pay the study

Provide the following data to EC Research on submission of a commercial study:

  • Invoicing address (preferably an address in Belgium)
  • Name of contact
  • PO number (Purchase Order), if applicable
  • VAT number

You will receive an invoice from the Financial department of UZ Leuven (with payment reference).

Payment is only possible upon receipt of an invoice of the Financial department.

Use of data for research

Scientific research is part of UZ Leuven's missions, alongside patient care and education. Any research project involving the processing of personal data must be submitted to EC Research.

Typically, scientific research is conducted either on the basis of pre-existing data (referred to as re-use of data) collected in the context of healthcare or a previous scientific study (this is termed retrospective research, wherein no new data regarding a patient or study participant may be obtained in any way), or by collecting new data specifically for the purpose of a particular study and using them, whether or not in combination with older data from participants, for the purpose of the study (referred to as prospective research).

At UZ Leuven, great importance is attributed to safeguarding patient privacy during scientific research. Medical data is categorized as sensitive data. Even if they can save lives, we have to handle them carefully. The patient's identity is well protected and is not shared. For more information, please refer to the privacy regulations.

Scientific research serving the public Interest

As a university hospital, we have a legal duty to engage in scientific research and conduct clinical studies. In that case, UZ Leuven is the data controller. As a university hospital affiliated with KU Leuven, UZ Leuven should support science and education in the public interest. The processing of personal data is necessary to conduct research.

Academic retrospective studies

Any research project involving the processing of personal data must be submitted to EC Research to enable a "privacy check", among other things; this includes retrospective studies. A GDPR questionnaire was developed to facilitate such a privacy check and is an integral part of the registration process at EC Research. The GDPR questionnaire must be completed for each study or research project in which UZ/KU Leuven acts as a data controller or participating site (

In addition to facilitating the privacy check, this GDPR questionnaire serves another purpose: fulfilling the information obligation towards research participants (transparency): i.e. to provide a description of the purpose of the research. The sections under "Research" in the GDPR questionnaire are automatically included in Mynexuzhealth. Research participants are informed about the studies in which their data are processed after being flagged with the corresponding S number in KWS. In Mynexuzhealth, the description of the study can consequently be found, and this under "Projects".

Scientific research outside the public interest

UZ Leuven engages in scientific research independently as well as in collaboration with academic or industrial partners, both of which are essential for maintaining the same high standard of care for everyone in the long run.

The patient's identity must be well protected and must not be shared. Only necessary data for advancing knowledge are utilized, with patient names never disclosed. Additionally, any information that could potentially lead to identification is not shared with external entities. In other words, the data we use is pseudonymised.

In cases where scientific studies are conducted outside the public interest, patients are provided with the option to oppose such data reuse through an 'opt-out' mechanism applicable to all future uses.

The opt-out option can be communicated through various ways:  

Also, when UZ Leuven data is processed in a retrospective study outside public interest, the GDPR questionnaire should be completed and submitted to EC Research. Patients will be informed about the study, via the mynexuzhealth app under "Projects". 

Last edit: 18 April 2024