Join our research!

What is the Cladis research participants registry?

The CLaDis subject database is a database of children aged 0 to 18 years, with and without language disorders, who would like to participate in one of our research projects. Parents can register one or more children if they wish.

Why make such a database?

We spend a lot of time searching for participants for research. There are also a lot of people out there who would like to participate, but may not be reacheable via our usual contacts. We want to make this process easier for participants and researchers, by having a research participants registry.

What information is registered?

We ask you for information about the age of your child(ren), language use and other demographic information about your family. We also ask what diagnosis of speech or language disorders they have, if any. We also ask for your contact details so that we can contact you about specific research projects.

How is our data processed?

To register for participation in CLaDis research, we need specific information from you. This data is stored in our CLaDis database, which is located on a secure server within the University of Groningen. Only staff members of the University of Groningen involved in the CLaDis research have access to this database. We will only contact you because of your participation in research at the CLaDis lab.

We store the information you provide for an indefinite period. Nevertheless, you can decide to unsubscribe at any time by sending us an email to After receiving your request, we will make your personal information, such as name, (email) address and telephone number, invisible in our database.

The processing of the aforementioned personal data is legally based on your consent. You give permission by registering as a test subject via the registration form.

Can my child participate if they are bilingual or multilingual?

Yes! A lot of our research is about performance within the Dutch language, so most of the tests are in Dutch. However, sometimes children can also speak a different language. For parents who do not speak Dutch, we also use translated forms. Our team is very international too!

When and where does the research take place?

We make appointments with parent at a place and time that works for them. The tests can be done at home, at the university or, for children who also do a brain scan, at the hospital in Groningen (UMCG).