Completing this thesis has been one of most arduous ordeals I have taken on, but also one of the most educational, satisfying, and now at the end of it all, liberating, empowering and relieving experiences I might ever have had. The relief of completing is most likely not only felt by me; I imagine several people around me may feel somewhat relieved themselves to see that I finally reached the finish line. Parallel to working on this thesis, these years since I first started have been the most eventful of my life, both good and bad. I lost a father, but gained the two great loves of my life; my daughters, Eira and Frida. These two little girls have no doubt largely contributed to keeping me sane throughout this process, and have reminded me along the way of what really matters. The same must be said for Vegard; I am profoundly thankful for your patience, support, and for being my rock in all our years together. Thank you. And to my family and friends, thank you all for your kind, supportive words and understanding. I would like to thank one person in particular who has been of invaluable support to me in all things that matter; my friend, colleague and co-author, Anne-Britt Skarbø. I cannot express how much I appreciate how you have encouraged and cheered me on throughout this long process, in moments when I needed it the most. A very special thank you also to cocheerleader and former colleague, Torhild Berntsen, a strong and inspiring advocate for children with acquired brain injury, who initiated the idea of a study investigating long-term functioning in survivors of childhood brain tumor, and who has believed in this study ever since. I am very proud to present the final product of this study! This is all my own product; from forming the idea for the project, to achieving funding, collecting data, and finally, reporting findings. However, none of this could have been achieved without my team players. First of all, to my main supervisor, Stein Andersson. Stein, you have been the ideal supervisor in my view; knowledgeable, steadfast, straightforward, encouraging, easy going, providing clarity and a dash of pragmatism, and calming my nerves in a moment or two of frustration. Thank you for sticking with me throughout this endeavor! Also, a special thank you to my cosupervisors, Ellen Ruud and Arnstein Finset. To Ellen, for immediately believing in and contributing to the project from the beginning, and for guiding me through the jungle that it is to implement a clinical study, and to Arnstein, for sharing your valuable academic experience and insights.

Completing this thesis has been one of most arduous ordeals I have taken on, but also one of the most educational, satisfying, and now at the end of it all, liberating, empowering and relieving experiences I might ever have had. The relief of completing is most likely not only felt by me; I imagine several people around me may feel somewhat relieved themselves to see that I finally reached the finish line. Parallel to working on this thesis, these years since I first started have been the most eventful of my life, both good and bad. I lost a father, but gained the two great loves of my life; my daughters, Eira and Frida. These two little girls have no doubt largely contributed to keeping me sane throughout this process, and have reminded me along the way of what really matters. The same must be said for Vegard; I am profoundly thankful for your patience, support, and for being my rock in all our years together. Thank you. And to my family and friends, thank you all for your kind, supportive words and understanding. I would like to thank one person in particular who has been of invaluable support to me in all things that matter; my friend, colleague and co-author, Anne-Britt Skarbø. I cannot express how much I appreciate how you have encouraged and cheered me on throughout this long process, in moments when I needed it the most. A very special thank you also to cocheerleader and former colleague, Torhild Berntsen, a strong and inspiring advocate for children with acquired brain injury, who initiated the idea of a study investigating long-term functioning in survivors of childhood brain tumor, and who has believed in this study ever since. I am very proud to present the final product of this study! This is all my own product; from forming the idea for the project, to achieving funding, collecting data, and finally, reporting findings. However, none of this could have been achieved without my team players. First of all, to my main supervisor, Stein Andersson. Stein, you have been the ideal supervisor in my view; knowledgeable, steadfast, straightforward, encouraging, easy going, providing clarity and a dash of pragmatism, and calming my nerves in a moment or two of frustration. Thank you for sticking with me throughout this endeavor! Also, a special thank you to my cosupervisors, Ellen Ruud and Arnstein Finset. To Ellen, for immediately believing in and contributing to the project from the beginning, and for guiding me through the jungle that it is to implement a clinical study, and to Arnstein, for sharing your valuable academic experience and insights.

Adolescent survivors of pediatric brain tumor (PBT) are a sparsely studied subset of childhood cancer survivors. Sustaining a PBT may complicate the development of executive functions (EFs), which play a vital role in long-term psychosocial adjustment. In this study, 48 adolescent survivors and their parents completed questionnaires assessing EF, psychological symptoms, fatigue, and adaptive functioning, and 26 survivors underwent neuropsychological assessment. Survivors reported significantly more problems with adaptive functioning than a healthy control group, and this was most strongly associated to executive dysfunction, compared to psychological symptoms and fatigue. The findings have important implications for longterm follow-ups.