Cross¿cultural adaptation and validation of the universal Portuguese¿version of the Pediatric Functional Assessment of Chronic Illness Therapy ¿ Fatigue (pedsFACIT¿F) Karla P. Fernandes; Bruno S. Teixeira; Benjamin J. Arnold; Tânia M. da S. Mendonça; Sthela M. Oliveira; Carlos Henrique M. da Silva;