Els van de Vijver

113 18. DG N, SH O, D G. Nathan and Oski's hematology of infancy and childhood. Company WS, editor. Philadelphia2003. 19.WHO. Serum ferritin concentrations for the assessment of iron status and iron deficiency in populations. Geneva: World health Organization; 2011 [htt p:/ /www.who.int/ vmnis/indicators/serum_ferritin . pdf , accessed octobre 2018).]. 20. Turner D, Otley AR, Mack D, Hyams J, de Bruijne J, Uusoue K, et al. Development, validation, and evaluation of a pediatric ulcerative colitis activity index: a prospective multicenter study. Gastroenterology. 2007;133(2):423-32. 21. Turner D, Griffiths AM, Walters TD, Seah T, Markowitz J, Pfefferkorn M, et al. Appraisal of the pediatric Crohn's disease activity index on four prospectively collected datasets: recommended cutoff values and clinimetric properties. Am J Gastroenterol. 2010;105(9):2085-92. 22. Varni JW, Burwinkle TM, Szer IS. The PedsQL Multidimensional Fatigue Scale in pediatric rheumatology: reliability and validity. J Rheumatol. 2004;31(12):2494-500. 23. Nap-van der Vlist MM, Dalmeijer GW, Grootenhuis MA, van der Ent CK, van den Heuvel-Eibrink MM, Wulffraat NM, et al. Fatigue in childhood chronic disease. Arch Dis Child. 2019. 24. Gordijn M, Cremers EM, Kaspers GJ, Gemke RJ. Fatigue in children: reliability and validity of the Dutch PedsQL Multidimensional Fatigue Scale. Qual Life Res. 2011;20(7):1103-8. 25. Kobayashi K, Okano Y, Hohashi N. Reliability and validity of the PedsQL Multidimensional Fatigue Scale in Japan. Qual Life Res. 2011;20(7):1091-102. 26. Varni JW, Beaujean AA, Limbers CA. Factorial invariance of pediatric patient self- reported fatigue across age and gender: a multigroup confirmatory factor analysis approach utilizing the PedsQL Multidimensional Fatigue Scale. Qual Life Res. 2013;22(9):2581-94. 27. Loonen HJ, Grootenhuis MA, Last BF, de Haan RJ, Bouquet J, Derkx BH. Measuring quality of life in children with inflammatory bowel disease: the impact-II (NL). Qual Life Res. 2002;11(1):47-56. 28. Griffiths AM, Nicholas D, Smith C, Munk M, Stephens D, Durno C, et al. Development of a quality-of-life index for pediatric inflammatory bowel disease: dealing with differences related to age and IBD type. J Pediatr Gastroenterol Nutr. 1999;28(4):S46-52. 29. Heida A, Park KT, van Rheenen PF. Clinical Utility of Fecal Calprotectin Monitoring in Asymptomatic Patients with Inflammatory Bowel Disease: A Systematic Review and Practical Guide. Inflamm Bowel Dis. 2017;23(6):894-902. 30. Geiger R, Strasak A, Treml B, Gasser K, Kleinsasser A, Fischer V, et al. Six-minute walk test in children and adolescents. J Pediatr. 2007;150(4):395-9, 9.e1-2. 31. Lammers AE, Hislop AA, Flynn Y, Haworth SG. The 6-minute walk test: normal values for children of 4-11 years of age. Arch Dis Child. 2008;93(6):464-8. 32. Ulrich S, Hildenbrand FF, Treder U, Fischler M, Keusch S, Speich R, et al. Reference values for the 6-minute walk test in healthy children and adolescents in Switzerland. BMC Pulm Med. 2013;13:49. 33. den Boer SL, Flipse DH, van der Meulen MH, Backx AP, du Marchie Sarvaas GJ, Ten Harkel AD, et al. Six-Minute Walk Test as a Predictor for Outcome in Children with Dilated Cardiomyopathy and Chronic Stable Heart Failure. Pediatr Cardiol. 2017;38(3):465-71. Self-reported fatigue and biological and functional parameters 113

RkJQdWJsaXNoZXIy ODAyMDc0