Objective: The PedsQL� Rheumatology Module is currently the only available measure of disease-specific Quality of Life (QOL) for children and adolescents with juvenile fibromyalgia (JFM) but limited information has been published about the psychometric properties of the instrument specifically in JFM. The objective of this study was to assess the reliability, 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 clinical trial in JFM. Methods: The entire PedsQL� Rheumatology Module was administered as a supplementary outcome measure at pre-treatment, post-treatment and 6-month follow-up assessments of 114 children and adolescents with JFM enrolled in a trial testing the efficacy of cognitive-behavioral therapy (CBT). Results: Results indicated that internal consistency reliabilities for the scales were adequate to strong (Cronbach ?s 0.68 - 0.86). Parent- proxy and child reports on most scales (except for daily activities and communication) showed moderate correlations (Spearman rs 0.33- 0.45). Support for construct validity was found based on comparing child and parent reports with other related measures of pain and functioning (Visual Analog Scale pain ratings and the Functional Disability Inventory). Finally, sensitivity to change was demonstrated by significant changes in 4/5 of the scales (excluding the daily activities scale) after treatment. Conclusion: The PedsQL� Rheumatology Module generally appears to have good utility for use in JFM patients but some caveats to interpretation of the specific scales in this population are discussed. � 2013 American College of Rheumatology.