FAQ (Frequently Asked Questions)

Multiples of any age may register. It does not matter whether you are identical or fraternal, or if you do not know whether you are identical or fraternal. In addition, family members can register and participate in family-based studies.

Twins and higher-order multiples who have registered with GERTRUD receive an email containing a registration link for their relatives. Relatives can register with GERTRUD via this link.

Yes. However, please note that many studies will require the participation of both you and your twin.

Yes. For most of the studies, only twins who are already registered as pairs will be invited. Therefore, to ensure you do not miss out on any studies, you should both register with GERTRUD. The first person to register will receive a personal link that they can share with their twin and other family members. This allows us to link registrations from the same family.

Signing up with GERTRUD is completely free. For most studies, you will receive financial compensation for participation.

Yes, not all studies take place on-site. Many studies can also be done remotely. However, please note that at least one twin must reside in Germany.

Yes. GERTRUD is a registry for twins as well as higher-order multiples.

Yes. You are welcome to register for GERTRUD regardless of whether you have a physical or mental impairment.

If you are invited to participate in an in-person study, please inform the research staff about the nature of your impairment so that we can accommodate your needs.

GERTRUD traces its origins back to the original project title: "GERman Twin Registry Under Development." Although the registry is no longer in the development phase, the name has become firmly established, both internally and externally, since the very beginning, and has truly grown on us. That is why we are keeping the name!

This depends on the types of studies currently being offered by researchers and whether you meet the inclusion criteria. However, we anticipate you will be contacted approximately 2–3 times a year regarding new studies.

This varies from study to study. Therefore, please read the study information for the respective study carefully and contact the study coordinators if you have any questions.

We will send you an email containing key information regarding new studies. If you are interested, you may contact the institute offering the study directly. Furthermore, if you would like to see which studies are currently being offered, you can view them here. If you are interested in a specific study and meet the listed criteria, you are also welcome to contact the researchers directly.

Your data will be stored pseudonymously. This means your research data will be linked to a code and not stored with your name. In scientific publications, your data will only be published in a way that does not allow any conclusions to be drawn about your identity. Please read our privacy policy for more information.

In that case, please send us an email to gertrud-datenschutz@mpib-berlin.mpg.de. Your information will then be deleted from the database.

Important:
This will not delete your contact information or research data that you provided for studies in which you participated through GERTRUD. For these, please contact the respective institutes directly.

The twin registry GERTRUD is based on the participant database Castellum. Castellum is a web application developed at the MPIB for the data protection-compliant management of participant data.