Ngai, Shirley P.C., Roy T.H. Cheung, Priscillia L. Lam, Joseph K.W. Chiu, and Eric Y.H. Fung. “Validation and Reliability of the Physical Activity Scale for the Elderly in Chinese Population”. Journal of Rehabilitation Medicine 44, no. 5 (March 15, 2012): 462–465. Accessed April 30, 2024. https://medicaljournalssweden.se/jrm/article/view/16049.