?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.aufirst=AG&rft.aulast=O'Keeffe&rft.au=O'Keeffe%2C+AG&rft.pages=675+-+699&rft.volume=60&rft.issue=5&rft.atitle=A+case-study+in+the+clinical+epidemiology+of+psoriatic+arthritis%3A+Multistate+models+and+causal+arguments&rft.title=Journal+of+the+Royal+Statistical+Society%3A+Series+C+(Applied+Statistics)&rft.issn=0035-9254&rft.date=November+2011&rft.genre=article