The PedsQL rheumatology module is currently the only available measure of disease-specific quality of life for children and adolescents with juvenile fibromyalgia (FM), but limited information has been published about the psychometric properties of the instrument, specifically in juvenile FM. The objective of this study was to assess there liability, validity, and sensitivity to change of the 5 scales (pain and hurt, daily activities, treatment, worry, and communication) of the patient and parent proxy versions of the PedsQL rheumatology module in the context of a randomized controlled trial in juvenile FM.