Assessing fatigue and related factors in adolescents with familial Mediterranean fever (FMF): psychometric properties of the PedsQL Multidimensional Fatigue Scale.

Background: Fatigue is a common problem in pediatric rheumatic diseases and is associated with poor quality of life. However, no validated methods are available to measure fatigue in adolescents with familial Mediterranean fever (FMF). The aim of the study was to establish validity and reliability for the child self-report PedsQL Multidimensional Fatigue Scale (PedsQL-MFS) and to investigate the effects of physical characteristics, diseaserelated characteristics, sleep quality/duration, and the amount of physical activity on fatigue in adolescents with FMF.