Arthritis & Rheumatism Official Journal of the American College of Rheumatology Editor William P. Arend, MD University of Colorado Health Sciences Center, Box B-117 4200 East Ninth Avenue Denver, CO 80262 Clinical Associate Editor Sterling G. West, MD, Denver Associate Editors J. Woodruff Emlen, MD, Denver Richard Hamman, MD, DrPH, Denver V. Michael Holers, MD, Denver J. Roger Hollister, MD, Denver Halsted R. Holman, MD, Palo Alto Ray Kilcoyne, MD, Denver Brian L. Kotzin, MD, Denver Jerome Wiedel, MD, Denver Advisory Editors Steven B. Abramson, MD, New York Carlos A. Agudelo, MD, Atlanta Paul J. Anderson, MD, PhD, Boston Balu H. Athreya, MD, Philadelphia Robert M. Bennett, MD, Portland Ferdinand C. Breedveld, MD, Leiden Peter Brooks, MD, FRACP, Sydney Jill P. Buyon, MD, New York Steven E. Carsons, MD, Mineola Thomas R. Cupps, MD, Washington Lawren H. Daltroy, DrPH, Boston Maxime Dougados, MD, Pans Marc Feldmann, MB, BS, PhD, London Gary S . Firestein, MD, Sun Diego Jorg J. Goronzy, MD, PhD, Rochester Arthur P. Hall, MD, Boston David A. Horwitz, MD, Los Angeles Osvaldo Hubscher, MD, Buenos Aires Consultant Biostatistician Anna E. B a r h , PhD, Denver Committee for the Publication of A&R David A. Fox, MD, Chair, Ann Arbor Ellen M. Gravallese, MD, Boston Nancy J. Olsen, MD, Nashville Joel M. Kremer, MD, Albany Paul H. Plotz, MD, Bethesda Carolyn L. Yancey, MD, Landover Editorial Staff Jane S. Diamond, MPH, Managing Editor, Atlanta Patricia K. Higgins, Assistant Managing Editor, Atlanta Lesley W. Allen, Manuscript Editor, Atlanta Angela M. Wiens, Editorial Assistant, Atlanta Virginia A. Frazer, Assistant Editor, Denver Elisa C. Schulz, Production Editor, Philadelphia Gunnar Husby, MD, Oslo Joachim R. Kalden, MD, Erlangen Jeffrey N. Katz, MD, Boston Klaus E. Kuettner, PhD, Chicago Edward V. Lally, MD, Providence Pierre Miossec, MD, PhD, Lyon Roland W. Moskowitz, MD, Cleveland Haralampos M. Moutsopoulos, MD, Zoannina Jacob B. Natvig, MD, Oslo Gerald T. Nepom, MD, PhD, Seattle Kusuki Nishioka, MD, Kawasaki Nancy J. Olsen, MD, Nashville Gabriel S. Panayi, MD, MRCP, London Christine Parker, MD, Boston Jean-Pierre Pelletier, MD, Montreal Michelle Petri, MD, Baltimore Rosalind Ramsey-Goldman, MD, DrPH, Chicago Thomas J. Schnitzer, MD, PhD, Chicago Yuichi-Y Shiokawa, MD, Tokyo Leonard H. Sigal, MD, New Brunswick Alan J. Silman, MD, Manchester Josef S. Smolen, MD, Vienna Leon Sokoloff, MD, Stony Brook Alan M. Solinger, MD, Sun Diego Virginia D. Steen, MD, Pittsburgh Robert Terkeltaub, MD, Sun Diego Daniel E. Tracey, PhD, Cambridge L.B.A. van de Putte, MD, Nijmegen Wim B. van den Berg, PhD, Nijmegen Michael H. Weisrnan, MD, Sun Diego Cornelia M. Weyand, MD, PhD, Rochester Patience H. White, MD, Washington H. James Williams, MD, Salt Luke City Frederick Wolfe, MD, Wchita Moms Ziff, PhD, MD, Dallas AMERICAN COLLEGE OF RHEUMATOLOGY Arthur L. Weaver, MD, Lincoln, President William J. Koopman, MD, Birmingham, First Vice-president and President-Elect Ronald L. Kaufman, MD, MBA, Los Angeles, Secretary-Treasurer Mark Andrejeski, Atlanta, Executive Vice-President Published for the College by Lippincott-Raven Publishers Arthritis & Rheumatkm (ISSN 0004-3591) is published monthly for the American College of Rheumatolo by Lippincott-Raven Publishers, at 12107 Insurance Way, Hagerstown, MD 21740. Business offices are located at 227 East Washington Square, PhiladelpKa, PA 19106. Printed in the USA. Copyright 0 1996 by the American College of Rheumatology, Atlanta, Georgia. Printed on acid-free paper effectivewith volume 32, number 11. Periodicals postage paid at Hagerstown, Maryland, and additional mailing offices. Subscription information, orders, or nonmember changes of address: (except Japan) 12107 Insurance Way, Hagerstown, MD 21740, or call 1-800-638-3030. In Japan, contact Igaku-Shoin, Ltd, 1-28-36 Hon 0,Bunkyo-ku, 113 Tokyo, Japan. 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