1. Department of Rheumatology, Division of Immunity and Infection, Medical School, University of Birmingham, UK
2. Divisions of Allergy/Clinical Immunology, Montreal, Quebec, Canada; Divison of Clinical Epidemiology, Montreal General Hospital, 1650 Cedar Avenue, Montreal, Quebec, Canada H3G 1A4; Tel: (+1) 514 934 8292; Fax: (+1) 514 934 8293