Joint symmetry in early and late rheumatoid and psoriatic arthritis: comparison with a mathematical model.
Thursday, April 20th, 2000Related ArticlesJoint symmetry in early and late rheumatoid and psoriatic arthritis: comparison with a mathematical model.
Arthritis Rheum. 2000 Apr;43(4):865-71
Authors: Helliwell PS, Hetthen J, Sokoll K, Green M, Marchesoni A, Lubrano E, Veale D, Emery P
OBJECTIVE: To establish a mathematical model to predict the probability of symmetry of joint involvement as a function of the number of joints involved and to compare expected with actual probabilities in psoriatic arthritis (PsA) and rheumatoid arthritis (RA) and in early and late disease. METHODS: Random involvement of joints was assumed, and the binomial theorem was used to give the frequency distribution of involved joints as a function of each joint count. Ten joint pairs were included: shoulder, elbow, wrist, metacarpophalangeal joints, proximal interphalangeal (PIP) joints of the hands, hip, knee, ankle, metatarsophalangeal joints, and PIP joints of the feet. Observed probabilities were obtained from subjects with early (duration
PMID: 10765932 [PubMed - indexed for MEDLINE]
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