This cognitive-behavioral exposure / response prevention program is delivered intensively over two consecutive weeks, consisting of daily 2.5-hour sessions across 10 days. Each group includes 6-8 adolescents, with every participant paired with an individual therapist for each session, though therapists rotate daily. At the outset, adolescents receive workbooks and psychoeducation on the nature of obsessive thoughts and compulsive behaviors, along with strategies to manage symptoms and reduce impairment. The primary focus of the program is individualized exposure exercises conducted with a therapist during each session. Designed for adolescents aged 12-18, the program also includes parent sessions, in which parents learn to manage anxiety-driven behaviors at home and reduce family accommodation.

This cognitive-behavioral exposure / response prevention program is delivered intensively over two consecutive weeks, consisting of daily 2.5-hour sessions across 10 days. Each group includes 6-8 adolescents, with every participant paired with an individual therapist for each session, though therapists rotate daily. At the outset, adolescents receive workbooks and psychoeducation on the nature of obsessive thoughts and compulsive behaviors, along with strategies to manage symptoms and reduce impairment. The primary focus of the program is individualized exposure exercises conducted with a therapist during each session. Designed for adolescents aged 12-18, the program also includes parent sessions, in which parents learn to manage anxiety-driven behaviors at home and reduce family accommodation.

A questionnaire designed to assess executive functioning in children and adolescents aged 5 to 18 years (Gioia et al., 2000). The questionnaire consists of 86 items with three response options: never = 1, sometimes = 2, and often = 3. A higher score on the BRIEF indicates greater executive functioning difficulties. The first 72 items are divided into eight clinical subscales that measure different aspects of executive function. These clinical subscales fall under two broader indices: the Behavioral Regulation Index (BRI) and the Metacognition Index (MI), which together form a Global Executive Composite (GEQ) score. The psychometric properties of the Icelandic version have proven to be acceptable.

This is a semi-structured interview (Scahill et al., 1997) intended to assess the symptoms and severity of obsessive compulsive disorder in children and adolescents aged 6-17 years. The scores range from 0-40, a higher score indicating more OCD related impairment with a clinical cut-off score of 15. The interview is conducted either with both the child and parent present or, in some cases, separately. The interview method depends, among other things, on the child´s age and developmental level. This interview is widely used, both for clinical purposes and in research, and has been translated into many languages. Today, it is considered the gold standard for assessing the severity of OCD symptoms and treatment response and is the most commonly and widely accepted tool for such evaluations (Mataix-Cols et al, 2016; Skarphedinsson et al, 2017). The interview has demonstrated strong psychometric properties (Cook et al., 2015; Højgaard et al., 2017).

This is a 55-item questionnaire that assesses functional impairment due to OCD in the child's most important environments (home, school, and social situations) (Piacentini et al, 2007). Each question is rated on a Likert scale from 0-3 and a higher score indicates more OCD related impairment. The adolescents will complete the child/adolescent form and parents will complete the parent form.

This is a 19-item scale developed to assess the extent to which the family attempts to accommodate the child´s symptoms to reduce distress. The scale is completed by parents and includes items such as how much the family tries to reassure the child, alter plans and activities, or help the child to avoid objects, places, or situations that cause distress. Scores range from 0-48 and higher scores indicate more family accommodation. The scale has acceptable psychometric properties, including internal consistency of 0.90 and high correlation with the standardized Family Accommodation Interview (Pinto et al., 2013).