Table Of ContentComputers and Medicine
Helmuth F. Orthner, Series Editor
Springer-Science+Business Media, LLC
Computers and Medicine
Use and Impact of Computers in Clinical Medicine
James G. Anderson and Stephen J. Jay (Editors)
Information Systems for Patient Care
Bruce I. Blum (Editor)
A Clinical Information System for Oncology
John P. Enterline, Raymond E. Lenhard, Jr., and Bruce I. Blum
(Editors)
The PACE System: An Expert Consulting System for Nurses
Steven Evans
Evaluation Methods in Medical Informatics
Charles P. Friedman and Jeremy C. Wyatt (Editors)
HELP: A Dynamic Hospital Information System
Gilad J. Kuperman, Reed M. Gardner, and T. Allan Pryor
Expert Critiquing Systems
Perry L. Miller
Selected Topics in Medical Artificial Intelligence
Perry L. Miller (Editor)
Implementing Health Care Information Systems
Helmuth F. Orthner and Bruce I. Blum (Editors)
Computer-Assisted Medical Decision Making, Volume 1
James A. Reggia and Stanley Tuhrim (Editors)
Computer-Assisted Medical Decision Making, Volume 2
James A. Reggia and Stanley Tuhrim (Editors)
Nursing and Computers: An Anthology
Virginia K. Saba, Karen A. Rieder, and Dorothy B. Pocklington
(Editors)
Knowledge Engineering in Health Informatics
Homer R. Warner, Dean K. Sorenson, and Omar Bouhaddou
Homer R. Warner
Dean K. Sorenson
Omar Bouhaddou
Knowledge Engineering
in Health Informatics
Springer
Homer R. Warner, M.D., Ph.D. Dean K. Sorenson, Ph.D.
Former Chairman and Professor Assistant Research Professor
Emeritus Department of Medical Informatics
Department of Medical Informatics University of Utah School of Medicine
University of Utah School of Salt Lake City, UT 84132, USA
Medicine
Salt Lake City, UT 84132, USA
Omar Bouhaddou, Ph.D.
Chief Knowledge Engineer
Mosby Consumer Health
Salt Lake City, UT 84109, USA
Series Editor
Helmuth F. Orthner, Ph.D.
Professor of Medical Informatics
University of Utah Health Sciences
Center
Salt Lake City, UT 84132, USA
Library of Congress Cataloging-in-Publication Data
Warner, Homer R., 1922-
Knowledge engineering in health informatics 1 by Homer R. Warner,
Dean K. Sorenson, Omar Bouhaddou.
p. cm.-(Computers and medicine)
Includes bibliographical references and index.
Additional material to this book can be downloaded from http://extras.springer.com.
ISBN 978-1-4612-7299-1 ISBN 978-1-4612-1822-7 (eBook)
DOI 10.1007/978-1-4612-1822-7
1. Medicine-Decision making-Data processing. 2. Expert systems (Computer
science) 3. Knowledge acquisition (Expert systems) 4. Medical informatics.
5. Diagnosis-Data processing. 1. Sorenson, Dean K., 1947- . II. Bouhaddou,
Omar. III. Title. IV. Series: Computers and medicine (New York, N.Y.)
R859.7.D52W37 1997
610'.285'633-dc20 96-44233
Printed on acid-free paper.
© 1997 Springer Science+ Business MediaN ew York
Originally published by Springer-Verlag New York in 1997
Softcover reprint of the hardcover 1st edition 1997
Ali rights reserved. This work may not be translated or copied in whole or in part without the
written permission of the publisher (Springer-Science+Business Media, LLC), except for
brief excerpts in connection with reviews or scholarly analysis. Use in connection with
any form of information storage and retrieval, electronic adaptation, computer software,
or by similar or dissimilar methodology now known or hereatter developed is forbidden.
The use of general descriptive names, trade names, trademarks, etc., in this publication, even
if the former are not especially identified, is not to be taken as a sign that such names, as
understood by the Trade Marks and Merchandise Marks Act, may accordingly be used freely
by anyone.
While the advice and information in this book are believed to be true and accurate at the date
of going to press, neither the authors nor the editors nor the publisher can accept any legal
responsibility for any errors or omissions that may be made. The publisher makes no warranty,
express or implied, with respect to the material contained herein.
Production managed by Victoria Evarretta; manufacturing supervised by Jeffrey Taub.
Typeset by Best-set Typesetter Ltd., Hong Kong.
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ISBN 978-1-4612-7299-1 SPIN 10552855
Series Preface
This monograph series is intended to provide medical information scien
tists, health care administrators, physicians, nurses, other health care pro
viders, and computer science professionals with successful examples and
experiences of computer applications in health care settings. Through these
computer applications, we attempt to show what is effective and efficient,
and hope to provide guidance on the acquisition or design of medical
information systems so that costly mistakes can be avoided.
Health care provider organizations such as hospitals and clinics are
experiencing large demands for clinical information because of a transition
from a "fee-for-service" to a "capitation-based" health care economy. This
transition changes the way health care services are being paid for. Previ
ously, nearly all health care services were paid for by insurance companies
after the services were performed. Today, many procedures need to be
pre approved and many charges for clinical services must be justified to the
insurance plans. Ultimately, in a totally capitated system, the more patient
care services are provided per patient, the less profitable the health care
provider organization will be. Clearly, the financial risks have shifted from
the insurance carriers to the health care provider organizations. For
hospitals and clinics to assess these financial risks, management needs to
know what services are to be provided and how to reduce them without
impacting the quality of care. The balancing act of reducing costs but
maintaining health care quality and patient satisfaction requires accurate
information about the clinical services. The only way this information can
be collected cost effectively is through the automation of the health care
process itself. Unfortunately, current health information systems are not
comprehensive enough and their level of integration is low and primitive at
best. There are too many "islands" even within single health care provider
organizations.
With the rapid advance of digital communications technologies and the
acceptance of standard interfaces, these "islands" can be bridged to satisfy
v
vi Series Preface
most information needs of health care professionals and management. In
addition, the migration of health information systems to client/server com
puter architectures allows us to reengineer the user interface to become
more functional, pleasant, and also responsive. Eventually, we hope, the
clinical workstation will become the tool that health care providers use
interactively without intermediary data entry support.
Computer-based information systems provide more timely and legible
information than traditional paper-based systems. In addition, medical in
formation systems can monitor the process of health care and improve
quality of patient care by providing decision support for diagnosis or
therapy, clinical reminders for follow-up care, warnings about adverse drug
interactions, alerts to questionable treatment or deviations from clinical
protocols, and more. The complexity of the health care workplace requires
a rich set of requirements for health information systems. Further, the
systems must respond quickly to user interactions and queries to facilitate
and not impede the work of health care professionals. Because of this and
the requirement for a high level of security, these systems can be classified
as very complex and, from a developer's perspective, also as "risky"
systems.
Information technology is advancing at an accelerated pace. Instead of
waiting for 3 years for a new generation of computer hardware, we are now
confronted with new computing hardware every 18 months. The forthcom
ing changes in the telecommunications industry will be revolutionary.
Within the next 5 years, or so, new digital communications technologies,
such as the Integrated Services Digital Network (ISDN), Asynchronous
Data Subscriber Loop (ADSL) technologies, and very high speed local area
networks using efficient cell switching protocols (e.g., ATM), will change
not only the architecture of our information systems but also the way we
work and manage health care institutions.
The software industry constantly tries to provide tools and productive
development environments for the design, implementation, and mainte
nance of information systems. Still, the development of information sys
tems in medicine is an art, and the tools we use are often self-made and
crude. One area that needs desperate attention is the interaction of health
care providers with the computer. While the user interface needs improve
ment and the emerging graphical user interfaces form the basis for such
improvements, the most important criterion is to provide relevant and
accurate information without drowning the physician in too much (irrel
evant) data.
To develop an effective clinical system requires an understanding of
what is to be done and how to do it, and an understanding of how to
integrate information systems into an operational health care environment.
Such knowledge is rarely found in anyone individual; all systems described
in this monograph series are the work of teams. The size of these teams is
usually small, and the composition is heterogeneous, i.e., health profession-
Series Preface vii
als, computer and communications scientists and engineers, statisticians,
epidemiologists, etc. The team members are usually dedicated to working
together over long periods of time, sometimes spanning decades.
Clinical information systems are dynamic systems, their functionality
constantly changing because of external pressures and administrative
changes in health care institutions. Good clinical information systems will
and should change the operational mode of patient care, which, in turn,
should affect the functional requirements of the information systems. This
interplay requires that medical information systems be based on architec
tures that allow them to be adapted rapidly and with minimal expense. It
also requires a willingness by management of the health care institution to
adjust its operational procedures, and, most of all, to provide end-user
education in the use of information technology. While medical information
systems should be functionally integrated, these systems should also be
modular so that incremental upgrades, additions, and deletions of modules
can be done to match the pattern of capital resources and investments
available to an institution.
We are building medical information systems just as automobiles were
built early in this century, i.e., in an ad hoc manner that disregards even
existent standards. Although technical standards addressing computer
and communications technologies are necessary, they are insufficient. We
still need to develop conventions and agreements, and perhaps a few
regulations that address the principal use of medical information in com
puter and communication systems. Standardization allows the mass produc
tion of low-cost parts that can be used to build more complex structures.
What exactly are these parts in medical information systems? We need to
identify them, classify them, describe them, publish their specifications, and,
most importantly, use them in real health care settings. We must be sure
that these parts are useful and cost effective even before we standardize
them.
Clinical research, health services research, and medical education will
benefit greatly when controlled vocabularies are used more widely in the
practice of medicine. For practical reasons, the medical profession has
developed numerous classifications, nomenclatures, dictionary codes, and
thesauri (e.g., lCD, CPT, DSM-III, SNOMED, COSTAR dictionary codes,
BAlK thesaurus terms, and MESH terms). The collection of these terms
represents a considerable amount of clinical activities, a large portion of the
health care business, and access to our recorded knowledge. These terms
and codes form the glue that links the practice of medicine with the business
of medicine. They also link the practice of medicine with the literature of
medicine, with further links to medical research and education. Because
information systems are more efficient in retrieving information when con
trolled vocabularies are used in large databases, the attempt to unify and
build bridges between these coding systems is a great example of unifying
the field of medicine and health care by providing and using medical
viii Series Preface
informatics tools. The Unified Medical Language System (UMLS) project
of the National Library of Medicine, NIH, in Bethesda, Maryland, is an
example of such an effort.
The purpose of this series is to capture the experience of medical
informatics teams that have successfully implemented and operated medi
cal information systems. We hope the individual books in this series will
contribute to the evolution of medical informatics as a recognized profes
sional discipline. We are at the threshold where there is not just the need
but already the momentum and interest in the health care and computer
science communities to identify and recognize the new discipline called
Medical Informatics.
I would like to thank the editors of Springer-Verlag New York for the
opportunity to edit this series. Also, many thanks to the present and past
departmental chairmen who allowed me to spend time on this activity:
William S. Yamamoto, M.D., and Thomas E. Piemme, M.D., ofthe Depart
ment of Computer Medicine at George Washington University Medical
Center in Washington, D.C., and Homer R. Warner, M.D., Ph.D., and Reed
M. Gardner, Ph.D., of the Department of Medical Informatics at the Uni
versity of Utah Health Sciences Center in Salt Lake City, Utah. Last, but
not least, I thank all authors and editors of this monograph series for
contributing to the practice and theory of Medical Informatics.
HELMUTH F. ORTHNER
Preface
This book was conceived to meet three primary objectives. First, to make
known the principles and methods of knowledge engineering developed
over nine years of experience with the Iliad diagnostic medical expert
system. Second, to provide a textbook to be used for a course in knowledge
engineering in a medical informatics curriculum. Third, to provide "physi
cian hackers" and other neophytes with the necessary information and
software tools to develop their own expert systems.
We have attempted to keep the presentation generic, but have also tried
to use many examples. We have used examples from the Iliad medical
expert system throughout the book because that is the system we are most
familiar with. Other well-known comprehensive medical expert systems
include QMR and DXplain. And, there are many other more specialized
systems that have been reported, both in the U.S. and elsewhere. Many
systems attest to the need that has been recognized and to the potential
usefulness that many have tried to fill. The field is rapidly changing for
a number of reasons, e.g., many disciplines are involved, funding and
management of healthcare in general is in a rapid state of flux, and the
underlying basic science that explains disease etiology and drives the devel
opment of new therapies is rapidly changing. There is no perfect medical
expert system; each has strengths and weaknesses. Likewise, there is no
knowledge engineering method that has been proved to be superior to all
others.
It is our hope that readers of this book will come to appreciate the power
and sophistication of the Iliad expert system. It is also our hope that many
of the principles described here will be applicable to other medical expert
systems and to other knowledge engineering environments. We have at
tempted here to formulate general concepts and principles where possible
and to point up potential problems in the knowledge engineering process
ix
x Preface
necessary to build medical expert systems. The methods proposed here
are not necessarily the only methods or the best methods for any given
situation.
HOMER R. WARNER
DEAN K. SORENSON
OMAR BOUHADDOU
