Clinical validation of an Internet-based questionnaire for ascertaining hip and knee osteoarthritis C. Ratzlaff, M. Koehoorn, J. Cibere, J. Kopec Osteoarthritis and Cartilage Volume 20, Issue 12, Pages 1568-1573 (December 2012) DOI: 10.1016/j.joca.2012.08.017 Copyright © 2012 Osteoarthritis Research Society International Terms and Conditions
Fig. 1 Subject recruitment. Osteoarthritis and Cartilage 2012 20, 1568-1573DOI: (10.1016/j.joca.2012.08.017) Copyright © 2012 Osteoarthritis Research Society International Terms and Conditions