Obsessive compulsive disorder is a severely disabling anxiety disorder that affects approximately 2% worldwide. The symptoms often result in serious difficulties in building and maintaining (social) relationships and in problems at work. Despite the existence of effective treatments, about half of the patients keep experiencing symptoms throughout their life. At present, we are clueless as to why these patients do not overcome OCD.

Internationally, NOCDA is one of the first studies to follow a large cohort of OCD patients (N=419) for multiple years in order to determine which biological, psychological, and social factors characterise a chronic course.

In order to enable the NOCDA study, several organisations have joined forces: VU medical centre (VUmc), GGZ inGeest, GGZ Centraal innova, Pro Persona, Mondriaan Academic Anxiety Centre Maastricht, Dimence, Leids University Medical Centre (LUMC), and Vincent van Gogh Institute.  These constitute the Dutch OCD association.