Intellectual disability (ID) affects a person throughout life and includes difficulties to manage what is expected in everyday life based on age. One difficulty is to create strategies for and solve problems related to everyday occupations. Treatment options with good evidence to enhance occupational performance for persons with ID are limited. The Cognitive Orientation to Daily Occupational Performance (CO-OP) is an approach with good evidence within other diagnostic groups, i.e. adolescents with cerebral palsy. CO-OP has a unique person-centered approach where the person chooses his/her own goals and creates his/her own strategies to reach them. Initial research shows potential for CO-OP with adolescents with ID, although due to scientific flaws there is still a lack of evidence regarding feasibility and effectiveness for adolescents with ID. Based on the results with other diagnostic groups and clinical knowledge and experience, CO-OP can be assumed to be feasible and effective for adolescents with ID and to have a long term effect transferred to everyday life in a way other treatment options do not.

The aim of the project is to describe and evaluate CO-OP for adolescents with mild ID. Participants will be adolescents aged 13-17 and their parents. The project is designed as a feasibility study with two qualitative, one quantitative and one mixed method data collection. The quantitative data will be ordinal and nominal data from observational and self-assessment assessments. The mixed methods include comparison between filmed sessions and the CO-OP manual, use of field notes to analyse fidelity and needs for adaptations, and comparison between the CO-OP manual and policy documents. The qualitative outcome will be experiences by the adolescents and perceptions of CO-OP by parents.

Study I-II

Inclusion criteria

• 13-17 years
• Diagnosed mild intellectual disability
• Motivation to reach self-selected goals
• Ability to identify those goals
• Possibility to meet once a week for ten weeks
• Access to a parent or significant other for support during intervention

Exclusion criteria:

• Movement related diagnosis (i.e. cerebral palsy or neuro muscular diseases)
• Diagnosed attention deficit hyperactivity disorder/attention deficit disorder (ADHD/ADD) or autism spectrum disorder
• Progressive diagnoses
• Need for language interpreting
• Need for alternative and augmentative communication (i.e. pictures or signs).

Study III

Inclusion criteria:

• 13-17 years
• Diagnosed mild intellectual disability
• Completed CO-OP intervention or at lest half way trough the intervention
• Opportunity to meet physically for an interview with in a month post and 6 months post intervention.
• CO-OP intervention done with high fidelity to CO-OP format with a CO-OP therapist that has written field notes, preferrably recruited from study I-II.

Exclusion criteria:

• Movement related diagnosis (i.e. cerebral palsy or neuro muscular diseases)
• Diagnosed attention deficit hyperactivity disorder/attention deficit disorder (ADHD/ADD) or autism spectrum disorder
• Progressive diagnoses
• Need for language interpreting
• Need for alternative and augmentative communication (i.e. pictures or signs).

Study IV

Inclusion criteria:

• Parents with legal guardianship that lives full- or part time with an adolescent reaching the inclusion criteria for study I who has completed CO-OP within or out of the project
• Opportunity to meet physically for an interview with in a month post and 6 months post the adolescent's completed, or at least half way through, CO-OP intervention.

Exclusion criteria:

• Need for language interpreting
• Need for alternative and augmentative communication (i.e. pictures or signs)
• Irregular and brief living with the adolescent comparable to less than half-time and therefore does not observe the adolescent's occupational performance enough to answer the interview questions.

One of the outcomes will be assessed using video from baseline, post and 6 months post intervention, and the assessor of those videos will be blinded to the order and have no knowledge about the participant.