clinical calculator for rheumatoid arthritis likelihood

summary, references, & relevant links
Summary: Rheumatoid arthritis clinical decision tool calculates likelihood of the disease.
References: Am Fam Physician. 2008 May 15;77(10):1451-1453 van der Helmvan Mil AH, le Cessie S, van Dongen H, Breedveld FC, Toes RE, Huizinga TW. A prediction rule for disease outcome in patients with recent-onset undifferentiated arthritis: how to guide individual treatment decisions. Arthritis Rheum. 2007;56(2):433–440.
See also the 2010 American College of Rheumatology/European League Against Rheumatism Criteria calculator at http://www.soapnote.org/musculoskeletal/2010-ra-criteria/.