The Physical Activity and Fitness in Childhood Cancer Survivors (PACCS) Study: Protocol for an International Mixed Methods Study oleh Hanne C Lie, Sigmund Anderssen, Corina Silvia Rueegg, Truls Raastad, May Grydeland, Lene Thorsen, Trine Stensrud, Elisabeth Edvardsen, Marie Hamilton Larsen, Ingrid Kristin Torsvik, Lars Peder Bovim, Miriam Götte, Päivi Maria Lähteenmäki, Susi Kriemler, Hanne Bækgaard Larsen, Martin Kaj Fridh, Kristin Ørstavik, Henrik Brun, Iren Matthews, Else Hornset, Ellen Ruud