Acknowledgements
We thank the participants and their parents, who graciously gave their time to participate in this study. This study received financial support from the Alma and K. A. Snellman Foundation, Oulu, Finland; the Emil Aaltonen Foundation, Finland; Northern Ostrobothnia Hospital District; the Sigrid Jusélius Foundation, Finland; the Thule Institute, University of Oulu, Finland; the Child Psychiatric Research Foundation, Finland. The Graduate School of Circumpolar Wellbeing, Health and Adaptation is acknowledged for its support. We would also like to thank the National Alliance for Autism Research for financial support granted to David Pauls. For data collection we wish to thank Child Psychiatrist, PhD Sirkka-Liisa Linna and PhD Marko Kielinen.