Journal of Clinical Epidemiology

Journal of Clinical Epidemiology Including Pharmacoepidemiology Reports Editors J. ANDRÉ KNOTTNERUS Maastricht, The Netherlands Professor of General Practice, Netherlands School of Primary Care Research. President, Health Council of the Netherlands

PETER TUGWELL Ottawa, Ontario Director, Centre for Global Health, University of Ottawa, Institute of Population Health

Editors Emeritus Journal of Chronic Diseases DAVID P. EARLE Chicago, IL

LOUIS LASAGNA Boston, MA

Journal of Clinical Epidemiology WALTER O. SPITZER Kingston, Ontario

JAN P. VANDENBROUCKE Leiden, The Netherlands

ALVAN R. FEINSTEIN (Deceased) New Haven, CT

Policy Advisory Board PAUL. B. BEESON Redmond, WA BERNARD BÉGAUD Bordeaux Cedex, France PETER BURNEY London, England LEIGHTON E. CLUFF

SERGIO ERILL Barcelona, Spain MICHEL A. IBRAHIM Chapel Hill, NC LOUIS LASAGNA Boston, MA

ROBERT G. PETERSDORF Seattle, WA

WALTER O. SPITZER Corpus Christi, TX BENEDETTO TERRACINI Torino, Italy

Gainesville, FL

Editorial Consultants Board RENALDO N. BATTISTA Montreal, Quebec

GORDON H. GUYATT Hamilton, Ontario

CALVIN M. KUNIN Columbus, OH

BRUCE E. RODDA Austin, TX

NATHANIEL I. BERLIN Miami, FL

FRANK E. HARRELL, JR. Charlottesville, VA

LEONARD T. KURLAND Rochester, MN

FRITS ROSENDAAL Leiden, The Netherlands

NORMAN F. BOYD Toronto, Ontario

GERRY B. HILL Rockland, Ontario

JOHN F. KURTZKE Washington, DC

RICARD B. SHEKELLE Houston, TX

RALPH I. HORWITZ New Haven, CT

VALERIE A. LAWRENCE San Antonio, TX

GIANNI TOGNONI Milano, Italy

THOMAS A. HUTCHINSON Montreal, Quebec

STEPHEN R. LEEDER Westmead, Australia

HERMAN TYROLER Chapel Hill, NC

MILOS JENICEK Montreal, Quebec

JACQUES LELORIER Montreal, Quebec

PAOLO VINEIS Torino, Italy

ROBERT L. KANE Minneapolis, MN

JOHN M. LEVENTHAL New Haven, CT

EDWARD H. WAGNER Seattle, WA

WILLIAM B. KANNEL Boston, MA

ALF L. NALCHEMSON Gotenburg, Sweden

GEORGE W. WILLIAMS Blue Bell, PA

STANISLAV V. KASL New Haven, CT

ADRIAN M. OSTFELD New Haven, CT

J. IVAN WILLIAMS Toronto, Ontario

PAUL KNIPSCHILD Masstricht, The Netherlands

PETER PEDUZZI West Haven, CT

T. FRANKLIN WILLIAMS Bethesda, MD

THOMAS KOTTKE Minneapolis, MN

MIQUEL S. PORTA Barcelona, Spain

SHARON WOOD-DAUPHINEE Montreal, Quebec

JOSEPH L. FLEISS New York, NY

MICHAEL S. KRAMER Montreal Quebec

DAVID F. RANSOHOFF Chapel Hill, NC

HENRIK R. WULFF Herlev, Denmark

HARRY A. GUESS Blue Bell, PA and Chapel Hill, NC

LEWIS H. KULLER Pittsburgh, PA

ALFRED A. RIMM Cleveland, OH

LAWRENCE M. BRASS West Haven, CT MARY E. CHARLSON New York, NY JOHN CONCATO West Haven, CT ALLEN S. DETSKY Toronto, Ontario THEODORE C. EICKHOFF Denver, CO JOHN M. ESDAILE Vancouver, B.C. MANNING FEINLEIB Hyattsville, MD

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