Developing good self-regulation skills is one of the most important tasks for a child to accomplish. Earliest signs of difficulties in self-regulation include excessive crying, sleeping, or feeding difficulties, which are labelled as ‘regulatory problems’. Increasing evidence has shown that regulatory problems in infancy/toddlerhood increase the risk of several negative outcomes such as attention problems, emotional and behavioral dysregulation in childhood, and depressive symptoms in adolescence. However, it remains unknown if regulatory problems in infancy/toddlerhood are also associated with adverse health and social outcomes in adolescence.

The current study aims to investigate whether regulatory problems in infancy/toddlerhood increase the risk of following adverse a) health outcomes in adolescence: harmful drinking, smoking, cannabis use, illicit drug use, problem gambling, unwanted pregnancy, obesity, excessive screen time, and self-harm at 18 years, and b) social outcomes in adolescence: getting into trouble with police, not being in education, employment or training (NEET), low peer social support, low closeness in romantic relationships and relationship with parents.