title: Physical Activity as an Outcome Measure for Patients With Hip or Knee Osteoarthritis: Comment on the Article by Rolfson et al.
authors.affiliation: Leiden University Medical Center, Leiden, The Netherlands.
authors.forename: Maaike G J
authors.initials: MGJ
authors.lastname: Gademan
authors.affiliation: Leiden University Medical Center and Rijnlands Rehabilitation Center Leiden, The Netherlands and Sophia Rehabilitation, The Hague, The Netherlands.
authors.forename: Thea P M
authors.initials: TPM
authors.lastname: Vliet Vlieland
mesh_terms: D032921:Consensus; D015444:Exercise; D006801:Humans; D015207:Osteoarthritis, Hip; D020370:Osteoarthritis, Knee; D017063:Outcome Assessment, Health Care