Internet-delivered CBT for Irritable Bowel Syndrome in Adolescents

Inclusion Criteria: * Age 13-17 at inclusion date. * fulfilling Rome III-criteria for IBS with a written statement from patient's physician confirming a diagnosis of IBS and negative required tests (Blood samples: C-reactive protein or erythrocyte sedimentation rate, Blood count and IgA-Transglutaminase. Stool: f-Calprotectin). Exclusion Criteria: * concurrent serious medical conditions. * a psychiatric diagnosis, judged to be a more important treatment target than the abdominal pain. * on-going psychological treatment. * absence from school exceeding an average of 2 days a week is a cause for exclusion since high absence demands more intensive interventions than can be offered in ICBT. * on-going abuse or severe parental psychiatric illness in the family. * since treatment format assumes normal reading and writing skills, pronounced language skill deficits and learning difficulties lead to exclusion from the study. * lack of regular internet-access.