OXFORD UNIVERSITY PRES Oxford University Press, Inc, publishes works that further Oxford Universitys objective excellence th scholarshi p, and education Oxford New York Auckland Cape Town Dar es Salaam Hong Kong Karachi Kuala Lumpur Madrid Melbourne Mexico City Nairobi Shanghai Taipei Toronto With offices in Argentina Austria Brazil zech Republic France Greece Guatemala Hungary Italy Poland Portugal Singapore Copyright o 1983, 1988, 1995, 2001, 2008 International Epidemiological Association, Inc. Published by Oxford University Press, Inc 198 Madison Avenue. New York. New York 10016 All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, ithout the prior permission of Oxford University Press. This edition was prepared with support from Esteve Foundation(Barcelona, Catalonia, Spain) Library of Congress Cataloging-in-Publication Data dictionary of epi edited for the International Epidemiological Association by Miquel Porta; associate editors, John M. Last.[ et al. ]-5the p cm. Includes bibliographical references and index ISBN978-0-19-5314496ISBN978-0-19-531450-2(pbk) 1. Epidemiology-Dictionaries I Porta, Miquel- I. International Epidemiological Association. A651D5532000 614403-dc2100-037504 246897531 Printed in the United States of AmericaOxford University Press, Inc., publishes works that further 1 Oxford University’s objective excellence in research, scholarship, and education Oxford New York Auckland Cape Town Dar es Salaam Hong Kong Karachi Kuala Lumpur Madrid Melbourne Mexico City Nairobi Shanghai Taipei Toronto With offi ces in Argentina Austria Brazil Chile Czech Republic France Greece Guatemala Hungary Italy Japan Poland Portugal Singapore South Korea Switzerland Thailand Turkey Ukraine Vietnam Copyright © 1983, 1988, 1995, 2001, 2008 International Epidemiological Association, Inc. Published by Oxford University Press, Inc. 198 Madison Avenue, New York, New York 10016 www.oup-usa.org All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the prior permission of Oxford University Press. This edition was prepared with support from Esteve Foundation (Barcelona, Catalonia, Spain) (http://www.esteve.org) Library of Congress Cataloging-in-Publication Data A dictionary of epidemiology / edited for the International Epidemiological Association by Miquel Porta; associate editors, John M. Last . . . [et al.].—5th ed. p. cm. Includes bibliographical references and index. ISBN 978–0-19–531449–6 ISBN 978–0-19–531450–2 (pbk.) 1. Epidemiology—Dictionaries. I. Porta, Miquel– II. International Epidemiological Association. RA651.D553 2000 614.4′03—dc21 00–037504 2 4 6 8 9 7 5 3 1 Printed in the United States of America on acid-free paper