NATIONAL ACADEMY PRESS
2101 Constitution Avenue, NW Washington, DC 20218
NOTICE: The project that is the subject of this report was approved by the Governing Board of the National Research Council, whose members are drawn from the councils of the National Academy of Sciences, the National Academy of Engineering, and the Institute of Medicine. The members of the committee responsible for the report were chosen for their special competences and with regard for appropriate balance.
This study was supported by Grant No. N0-0D-4-2139 between the National Academies and the National Institutes of Health of the U.S. Department of Health and Human Services. Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the views of the organizations or agencies that provided support for the project.
International Standard Book Number 0-309-07195-X
Additional copies of this book are available from the
National Academy Press
, 2101 Constitution Avenue, N.W., Box 285, Washington, DC 20055; (800) 624-6242 or (202) 334-3313 (in the Washington metropolitan area); http://www.nap.edu.
Copyright 2000 by the National Academy of Sciences. All rights reserved.
Printed in the United States of America