The prevalence of fibromyalgia in the general population: a comparison of the American College of Rheumatology 1990, 2010, and modified 2010 classification criteria - Jones, G T; Atzeni, F; Beasley, M; Flüß, E; Sarzi-Puttini, P; Macfarlane, G J (Arthritis Rheumatol, 2015)