TY - JOUR T1 - Drs. Dai and Felson reply JF - The Journal of Rheumatology JO - J Rheumatol DO - 10.3899/jrheum.201222 SP - jrheum.201222 AU - Zhaoli Dai AU - David T. Felson Y1 - 2020/10/15 UR - http://www.jrheum.org/content/early/2020/10/13/jrheum.201222.abstract N2 - We appreciate the interest and comments by Yang and Hung1 in our recent publication, “Sleep Quality Is Related to Worsening Knee Pain in Those with Widespread Pain: The Multicenter Osteoarthritis Study”2. Yang and Hung raised 3 issues about potential biases in the methodology in our study around (1) the assessment methods used for sleep quality, (2) confounding factors such as other pain medication used, and (3) the appropriateness of causality in the study conclusion1. ER -