The efficacy of the Small Step program is presently being investigated through a randomized controlled trial (NCT02166801) at Karolinska Institutet (KI) in Stockholm, Sweden. In the original project proposal for the current study, the plan was to contribute with inclusion of children from St. Olavs Hospital to the randomized controlled study initiated at KI. This project proposal has previously been approved by the Regional Ethical Committee (REK) for Medical Research in Mid-Norway (2016/1366). However, the researchers at KI have now completed the inclusion of participants for the randomized controlled study, and their preliminary results indicate that there is a large individual variation among the included participants regarding effect of the Small Step program. In agreement with the researchers at KI, it was therefore decided to change the design of the current study using Single Subject Research Design, a study design that is more appropriate to investigate individual response to treatment. The change in study design has been approved by REK (2016/1366-10).