The goal of RADAR is to investigate the normal, but also problematic development of adolescents. During high school, adolescents experience a period of major changes, such as changes in classmates and friends. But it is also a period of bodily changes, changes in behavior and in becoming more independent. During adolescence, there is an increased risk of depression and anxiety. Sometimes, antisocial behavior increases as well. Adolescence is therefore a period in which some adolescents develop problems, but others don’t.

In RADAR, we investigate which factors are associated with a healthy and a problematic development of adolescents.
By providing reliable information about possible causes and risk factors for developing problem behavior, support programs and interventions can be modified to become more effective.



To study the development of adolescents as precisely as possible, it is important to get a complete picture by looking at different developmental areas. Therefore, RADAR includes information about feelings, personality, self-image, empathy, stress resiliency, depression, anxiety, school/study/work experience, parenting, family relationships, peer relationships, partner relationships, but also aggressive behavior, delinquency, and substance use (alcohol, smoking, and drugs).

It is important to not only look at the adolescent, but also at his/her environment. Therefore, from 2005 to 2010, adolescents, their parent(s), brother or sister, and (best) friend were assessed annually, using questionnaires, interviews, interaction tasks, internet measurements, and lab tasks. This allows to look at social relationships from diverse perspectives, such as relationships between parent and adolescent, relationships between parents, relationships between brothers and sisters, and reciprocal friendships.

From 2010 onwards, the frequency of assessments was changed from annual  to biannual assessments. The focus shifted to the young adult and his/her romantic partner. The study now concentrates on the development from adolescence to (young) adulthood and the relationship between the young adult and his/her romantic partner.

Examples of our research

Recent publications