English information phase 5

Phase 5 is now started: questionnaire research

Now you are 15-16 years old, we ask you once again to fill in a questionnaire. This time via the ABCD-app! With this app we get information about, for example, sleep-, food pattern, physical activity and mental health. In addition, we also gather information about phone use. We won’t register what you are doing on your phone, but only how long the screen is on per day, how loud the volume is and how bright the screen is. Furthermore, we ask your mother and father to fill in a questionnaire. The parental questionnaires can be filled in online and contain questions about the health and behaviour of themselves and you, the ABCD child.

Download here the folder for further information:


Have you already received the login codes for the questionnaires via e-mail or post? If yes, below you can find the buttoms to the online questionnaire for parents:

If you have not received any information about phase 5 from us before the beginning of November 2019, we do not have the correct contact information from you. Have you moved or were there any changes in your contact information? Please let us know using the following form:


The previous measurement round took place in 2015-2016, at the age of 11-12 years. This is the 4th study phase of the ABCD-study. Did you not complete these questionnaires? No problem! You can participate in the 5th study phase of the ABCD-study. All information we receive from you is valuable and useful for our research.   


Physical measurements

During the 5th study phase, no physical measurements will be carried out. We have plans do this in future phases of the ABCD-study.