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Within a hospital, the need for a computer-based transfusion system has became mandatory. It facilitates the tracing of healthcare activities, which is the basis of the security of the care and a functional element of continuous quality improvement procedures. In order to implement this traceability, reactive and real-time information systems are needed close to healthcare participants, which is not the case of current information systems which rely on a recorded collection of data, far from the needs of the caregiver, and mainly answering to an objective evaluation of results. In the context of continuous quality improvement programmes started in our hospital, hemovigilance was the first to use a process analysis approach, from the prescription of blood units to their administration and follow-up. Several questions arise from this: 1) how to use the process analysis work to specify the users' needs of a generalized and real-time transfusion information system? 2) how to spread this model to other healthcare activities? 3) how to integrate or interface the whole of these quality programmes with a clinical information system? A user-centered methodology was used, based on 'usage cases'. For each step of the transfusion process, this method allowed us to specify participants, data necessary for an activity (observed, deduced or decision-support data), data issuing from the activity, roles (the interaction between user and activity) and functions (the result of the interaction between user and activity).

Introduction: The paper presents the new paradigm for medical practice which has been emerging for a decade: evidence-based medicine., Current Knowledge and Key Points: The paradigm proposes new skills for the physicians, de-emphasizing intuition and empiricism in medical practice, and proposes the intensive use of medical literature for the medical practice., Future Prospects and Projects: The article presents the main characteristics of the approach which is raising new important questions about the evolution of medical practice and the validity of the paradigm.

Hospital information systems have to support quality improvement objectives. The design issues of health care information system can be classified into three categories: 1) time-oriented and event-labelled storage of patient data; 2) contextual support of decision-making; 3) capabilities for modular upgrading. The elicitation of the requirements has to meet users' needs in relation to both the quality (efficacy, safety) and the monitoring of all health care activities (traceability). Information analysts need methods to conceptualize clinical information systems that provide actors with individual benefits and guide behavioural changes. A methodology is proposed to elicit and structure users' requirements using a process-oriented analysis, and it is applied to the field of blood transfusion. An object-oriented data model of a process has been defined in order to identify its main components: activity, sub-process, resources, constrains, guidelines, parameters and indicators. Although some aspects of activity, such as "where", "what else", and "why" are poorly represented by the data model alone, this method of requirement elicitation fits the dynamic of data input for the process to be traced. A hierarchical representation of hospital activities has to be found for this approach to be generalised within the organisation, for the processes to be interrelated, and for their characteristics to be shared.

This paper is the description of a French Virtual Medical University based on the federation of existing or currently being developed resources in several Medical Schools in France. The objectives of the project is not only to share experiences across the country but also to integrate several resources using the New Information and Communication Technologies to support new pedagogical approaches for medical students and also for continuing medical education. The project includes: A virtual Medical Campus using secure access from several sites, The Integration of new interactive resources based on pedagogical methods, Implementation of new indexing and search engines based on medical vocabularies and ontologies, The definition of general and specific portals, the evaluation of the system for ergonomics and contents.

The World Wide Web (web) provides the same type of information to widely different users and these users must then find the information suitable for their use in the package offered. The authors present the DI2ADEM project designed to take the user into account and intended to provide this user with appropriate medical information. To do that, DI2ADEM is suggesting an adaptive hypermedia based on the management of a meta-knowledge of the user and a knowledge of the information that can be circulated. An adaptive hypermedia prototype devoted to paediatric oncology was implemented on the intranet network of a university hospital.

Objectives: To design and implement mediators dedicated to access various kinds of information sources in the framework of the project ARIANE., Method: Mediators are dynamically built thanks to three components: pieces of knowledge issued from the UMLS knowledge sources and from a catalog of information sources, processes that translate a query into the syntax of a target source, and communication services provided by operating systems., Results: A scenario details the complete mediation process with an indexed web site., Conclusion: This approach mixes knowledge and software engineering. It benefits from services provided by operating systems and allows scalability and reusability of software components.

Hospital information systems have to support quality improvement objectives. The requirements of the system have to meet users' needs in relation to both the quality (efficacy, conformity, safety) and the monitoring of all health care activities (traceability). Information analysts need complementary methods to conceptualize clinical information systems that provide actors with immediate individual benefits and guide collective behavioral changes. A methodology is proposed to elicit users' needs using a process-oriented analysis, and it is applied to the field of blood transfusion. We defined a process data model, the main components of which are: activities, resources, constrains, guidelines and indicators. Although some aspects of activity, such as "where", "what else", and "why" are poorly represented by the data model alone, this method of requirement elicitation fits the dynamic of data input for the process to be traced. A hierarchical representation of hospital activities has to be found for this approach to be generalised within the organisation, for the processes to be interrelated, and for their characteristics to be assessed.

The increasing volume of information available on the Internet today is a problem for health care professionals who want to access rapidly data of high quality. Usual search engines and directories are not sufficient to satisfy their needs. Moreover, the information published by Web sites is not always guaranteed. Some institutions around the word deal with the definition of a set of criteria for the evaluation of medical Web sites. We base our current work on the technologies we developed previously in order to integrate sources of information of various kinds using the "Unified Medical Language System" knowledge bases. This paper focuses on quality criteria and access characteristics Web sites should satisfy to be registered in a "Health Internet Directory". The design of such a system is proposed and discussed.

Large information systems handle massive volume of data stored in heterogeneous sources of information. Each server has its own model of concepts representation with regard to its aims. One of the main problems encountered by end-users when accessing different servers is to match their own viewpoint on biomedical concepts with their various representations that are made in the database servers. The aim of the project ARIANE is to provide end-users with easy-to-use and natural means to access and query heterogeneous information databases. The objectives of this research work consist in building a conceptual interface by means of the Internet technology inside an enterprise Intranet, and to propose a method to realize it. Moreover, this method provides designers of web sites with a powerful tool to manage them on the basis of an ontology of the biomedical domain. This method is based on the knowledge sources provided by the Unified Medical Language System project of the U.S. National Library of Medicine and exploits intensively the conceptual graphs theory.

Information is usually available in heterogeneous data format and various legacy sources. Interoperability appears to be a major approach for applications to access information. The project ARIANE is devoted to provide end-users with an easy to use and natural access to information databases. In this frame we defined actors able to operate the mediation between end-users and information servers: a "broker" which selects appropriate resources and "mediators" which access data suppliers. We have implemented a web-oriented stand-alone prototype accessing three types of information sources: a bibliographical server, a SQL database server and a hypertext server. Both broker and mediators exploit the Unified Medical Language System knowledge sources, especially the Information Sources Map which allows a way to identify information servers.

Talking about the problems of integration in medical information systems, the necessity to provide end users with a consistent and coherent view of patient's data, has been largely reported. In order to attempt this goal, systems need to perform semantic integration. We propose a pragmatic way to describe the semantics of the elements of a database, based on a bottom-up three steps process: 1. a back documentation of the elements of the system from their description contained in the data catalog of the database 2. a first semantic extension to transform a data catalog into a data dictionary 3. a second semantic extension to create a dictionary of the medical concepts from a data dictionary. This dictionary of concepts can be considered as the final result of "semantic integration". It contains a set of entities directly understandable by the end users. These entities are deduced or built from the elements collected and characterized in the data dictionary. This work reports the conceptual analysis and the implementation of such a data dictionary.

The MAOUSSC (Model for Assistance in the Orientation of a User within Coding Systems) Web server supports a collaborative work on the description of medical procedures. The specifications for the MAOUSSC application are conceptual modeling, definition of semantically fully described procedures, re-use of an existing vocabulary, the UMLS, and sharability. This paper reports on some difficulties in applying those principles in a networked building and updating of the terminology. The users are physicians who have to represent procedure terms in the MAOUSSC formalism. They must apply the constraints of the underlying model, and re-use the representation of the UMLS knowledge base. In our experience, we found that the implementation of syntactic and semantic constraints was not sufficient. Guidelines for pragmatical aspects in representation are required to make a collaborative approach in terminology building more operational.

Several databases on drugs have been developed worldwide for drug information functions whose sources are now electronically available. Our objective was to implement one of them in our University hospitals information system. Thériaque is a database which contains information on all the drugs available in France. Before its implementation we modeled its content (chemical classes, active components, excipients, indications, contra-indications, side effects, and so on) following an object-oriented method. From this model we designed dynamic HTML pages according to the Microsoft's Internet Database Connector (IDC) technics. This allowed a fast implementation and does not imply to port a client application on the thousands of workstations over the network of the University hospitals. This interface provides end-users with an easy-to-use and natural way to access information related to drugs in an Intranet environment.

This paper describes our approach in analyzing the impact of the TOP-FORUM hypermedia in a pediatric oncology care unit. The impact of this technology is realized through the study of accommodation and assimilation adoption. Accommodation refers to the technological adoption and Assimilation refers to the professional adoption. Results show that accommodation depends on information and formation of the users. Assimilation is more difficult to evaluate because it depends on human, social and organizational problems.

A typology of medical informatics applications is proposed around three dimensions: the dimension of care, the dimension of information and knowledge, and the aspects of the computerized society. These dimension can help both to evaluate application or research papers in the field or to derive long term goals for the discipline. In the first dimension medical informatics appears more as a technology driven by external forces such as the general progress of medicine or the integration of economical constraints in the choice of optimal procedures. It is argued that barriers to overcome as well as challenges for future research mainly remain in the two last dimensions.

The Internet and the World Wide Web provide today end-users with capabilities to access universally to information in various and heterogeneous databases. The biomedical domain benefits from this new technology, specially for information retrieval by searching and browsing various sites. Nevertheless, end-users may be disoriented by specific ways to access information on different servers. In the framework of an Intranet design and development, we present a method for integrating information databases based on knowledge sources of the UMLS. The method provides designers of a Web site with facilities to implement an easy and homogeneous access to information. The pages are built dynamically and displayed according to a style sheet and their content stored in a database during the design phase. The database also describes the links between pages. Moreover, this organization provides administrators with powerful capabilities to manage Web sites.

Medical activity in learning stages or in usual tasks is a wide field for information technologies. But it would be a mistake to focus on technologies and minimize the organisational, social and cultural aspects of integrating such technologies. Medical hypermedia design based only on a technological approach is a case in point. This paper describes our experience in hypermedia development. It reports on the technical, methodological and organizational aspects destined to help the medical community get involved in the development of such applications.

The treatment of pediatric cancer patients is characterised by complex and aggressive chemotherapy, difficult decision making, the numerous protocols available and the necessity of highly skilled caregivers. Quality of care is a major issue in all pediatric oncology units. We created an interactive multi-media database available to each caregiver to permit him/her to have easy access to information and thus increase his/her knowledge and participate in increasing their group's know-how. The computer database is available to all on a free-access basis in each ward. This is a novel approach to quality care, as it accords great importance to personal formation, allowing each caregiver to broaden his/her knowledge via easily obtained data which he/she can help enrich by permanent feedback. This database may become the backbone of department know-how.

The health professional multimedia workstation is the natural entry point to health and knowledge networks. It should allow an easy and transparent management of all the data necessary for patient management. Multimedia nature of processed information reflects evolution of medical techniques that involve more and more complex objects such as video sequences or digitized signals. Workstations can be considered from 3 points of view: the professional end-users, the developers and the decision makers. The long term goal for the end-user is to establish an easy access in a working environment, that gives him/her the feeling of a single comprehensive application running on a single computer when the information system relies on a set of heterogeneous and geographically distributed components. Development of a workstation requires the integration into the same environment of tools to localize, access, manipulate and communicate the required information within a health information network. Analysis of the 445 Medline-indexed publications for the January 1991 to December 1994 period, that included the word workstation either in their title or in their abstract, helps in refining objectives and challenges both for the health professionals and the decision makers.

Medical activity is characterized by its complexity. Professional guidelines and good wills do not suffice to improve efficiently performances of decisions taken by health care workers, medical doctors and administrators. The evaluation medical activity is a necessity for assisted decision making. The finality of evaluation has to be specified, its methods must be adapted, so that it is accepted by the medical community. In this framework, data processing can be a tremendous way to improve continuously the efficiency of the health care system.

As information databases we consider all the collections of data records indexed by key-words, stored and delivered by computer systems. In previous research works we demonstrated the interest to design a conceptual model, in the conceptual graphs formalism, and to implement a computational model for information retrieval in large information databases. These models are based on the UMLS knowledge sources. This paper reminds briefly these models and describes tests done in querying a patients database and a bibliographical database.

The Unified Medical Language System (UMLS) of the U.S. National Library of Medicine is a complex collection of terms, concepts, and relationships derived from standard classifications. Potential applications would benefit from a high level representation of its components. This paper proposes a conceptual representation of both the Metathesaurus and the Semantic Network of the UMLS based on conceptual graphs. It shows that the addition of a dictionary of concepts to the UMLS knowledge base allows the capability to exploit it pertinently. This dictionary defines more precisely the core concepts and adds constraints on their use. Constraints are dedicated to guide an "intelligent" browsing of the UMLS knowledge sources.

Hypertext and hypermedia are used to access loosely structured information. The lack of conceptual model for hypertext application makes it difficult to represent the mental model of the author. Users are often lost in the information and the objective of the author is not achieved. In this paper, we describe an approach to handle information and knowledge in the FORUM hypermedia authoring system. It allows the author to create and maintain the hypertext more easily and facilitates the navigation of the reader. An application for learning uterine magnetic resonance imaging is also presented.

The re-usability of lexicons and knowledge in medicine is a crucial challenge. The Unified Medical Language System (UMLS) project has attempted to provide a repository of concepts, semantically categorized for biomedical domain. This paper describes some results about the relevance of UMLS structures for specific purposes. We have focused on the description of surgical procedures. Discussion concerns synonymy of terms, granularity of concepts, and ontology. A preliminary work on the exploitation of interconcept links by a computerized application reveals a heterogeneous implementation of those relationships. However, the UMLS provides a powerful knowledge base for developers.

As information databases we consider all the kinds of information repositories that are handled by computer systems. When querying very large information databases, the end-users are often faced with the problem to parse their questions efficiently into the query languages of the computer systems. Conceptual graphs were initially designed for natural language analysis and understanding. Due to their closeness to semantic networks, their expressiveness is powerful enough to be applied to knowledge representation and use by computer systems. This work demonstrates that conceptual graphs are a suitable means to model both the information in patient databases and the queries to these databases, and that operations on graphs can compute the pattern matching process needed to provide the answers. A prototype that exploits this model is presented. Experiments have been made with the material furnished by the Unified Medical Language System project (version 2, 1992) of the National Library of Medicine, USA.

Information and knowledge processing technologies have contributed to the development of Computer assisted instruction (CAI) applications. Multimedia technologies will increase the possibilities of these programmes in the future. However the evaluation of the software as well as the other technologies is necessary. The authors have tried to quantify the contributions of CAI analysing the literature referenced in MEDLINE from 1989 to 1992. On the 470 papers indexed with the key-word "Computer Assisted Instruction", 56 studies take evaluation into account. Only 26, that is 5.5%, presented a clear and explicit methodology of evaluation. On the 26 studies, 16 were considered with positive result and among these, 6 presented a statistical significance. The conditions and the criteria of the evaluation studies do not permit a meta analysis. Is is necessary to develop standardized evaluation criteria to estimate the quantitative and qualitative impact of the CAI technics on the educational process and their own pedagogical contribution.

The UMLS is a complex collection of interconnected biomedical concepts derived from standard nomenclatures. Designing a specific subset of the UMLS knowledge base relevant to a medical domain is a prerequisite for the development of specialized applications based on UMLS. We have developed a method based on the selection of the appropriate terms in original nomenclatures and the capture of a set of UMLS terms that are linked to them in the network to a certain degree. We have experimented it as the foundation for a concept base applied to urology. Results depend on the exhaustiveness of the relationships between the Metal concepts. A preliminary analysis of the sub-base reveals that some adaptations of vocabulary and ontology are required for clinical applications.

A high level representation of data would clarify the complex collection of medical concepts, terms and relationships derived from standard classifications that the Unified Medical Language System contains. A conceptual model is described which represents the data structure. A second objective of this conceptual model is to provide users with the capability to build queries to information databases as easily as possible on the basis of this data structure. The methods used to build this model are semantic networks and conceptual graphs. The object-oriented computational model which implements this conceptual model is detailed. It reuses part of the generic C++ classes of the National Institutes of Health library. New classes are added to this library to implement the needed functionalities.

Information retrieval in large information databases is a non-deterministic process which needs a sequence of search steps generally. One of the main problems to which the end-users are faced is to parse efficiently their questions into the query language that the computer systems allow. Conceptual graphs were initially designed for natural language analysis and understanding. Due to their closeness to semantic networks, their expressiveness is powerful enough to be applied to knowledge representation and use by computer systems. This work demonstrates that conceptual graphs are a suitable means to model the end-users querieson the basis of the thesaurus and the semantic network of the UMLS project.

We describe the FORUM project which is a computer-assisted learning tool written with hypertext and hypermedia software emphasizing student interaction. This project is designed to allow the user to teach himself uterine Magnetic Resonance Imaging, which is a rapidly expanding technique with a wealth of specific findings. The program is currently available for Apple personal computers and is intended for beginners or confirmed radiologists and gynaecologists.

The use of a taxonomy, such as the concept type lattice (CTL) of Conceptual Graphs, is a central structuring piece in a knowledge-based system. The knowledge it contains is constantly used by the system, and its structure provides a guide for the acquisition of other pieces of knowledge. We show how UMLS can be used as a knowledge resource to build a CTL and how the CTL can help the process of acquisition for other kinds of knowledge. We illustrate this method in the context of the MENELAS natural language understanding project.

The Relative Complexity Index beta (RCI beta) has been devised as an indicator of the relative complexity and cost of anaesthesia. It takes into account the type of anaesthesia, the duration, the type of surgery and the patients' ASA status. This study analyses the relative weight of each component of RCI by a multiple regression analysis. The results show the pre-eminence of the surgical procedure in the formula. The weight of surgical procedure is responsible of 80 p. cent of the model's variance. In these conditions, the RCI beta cannot be accepted as an accurate complexity index of anaesthesia.

In order to reduce the cost of a systematic heterozygote thalassemias screening, and using a discriminant analysis, the authors propose a pre-selection performed on the erythrocytometric data. In the present conditions of applicability, the methodology we used appears to be very efficient in the pre-screening process. An electrophoresis with the determination of hemoglobin A2 is then carried out on the pre-selected individuals as a confirmation of the diagnosis.

Using a directional Doppler (4 MHz) coupled to a frequency analyser, authors investigate the supra-aortic trunks on 90 patients documented by arteriography. The analyser is made of a 16 filter bank system giving a spectrum composed of 16 frequency bands within range of 160 Hz to 4,800 Hz. Data analysis is made on a computer using the comparison means test and the discriminant analysis. Authors compare frequencies on normal common carotid arteries between a group (N = 102) with internal and external carotid arteries free of lesions on one hand, and a group (N = 75) with stenosis or occlusion of internal and/or external carotid arteries on the other hand. They don't note any significant difference for each on of the 16 frequency bands. Comparison of frequencies between normal subclavian arteries (N = 115) and subclavian arteries with proximal stenosis or occlusion (N = 24) shows a significant difference concerning the following bands : F12, F14, F15, F16 (p = 0.05), F13 (p = 0.01). Comparison of frequencies between normal internal carotid arteries (N = 108) and stenosed internal carotid arteries (N = 57) shows significant difference concerning : F11 (p = 0.05), F7, F8, F9, F12, F13, F14, F15, F16 (p = 0.01). On the other side, the discriminant function distinguishes a normal internal carotid artery from a stenosed internal carotid artery in 90% of cases, whatever the stenosis degree is. A discriminant function, added to this analyser, could obtain a frequency analysis easier and less expensive than by fast Fourier transform.

The authors found a significant statistical correlation (linear and Spearman) between erythrocyte sedimentation rate (ESR), plasma fibrinogen level, alpha-2-globulins level, platelets count, anemia and age, in 1 000 patients admitted to the Hôtel-Dieu of Marseille. The high degree of partial correlations obtained, confirmed that a direct and independent relationship exists between ESR-fibrinogen, ESR - alpha-2-globulin, fibrinogen - alpha-2-globulin. Determinations of plasma fibrinogen and alpha-2-globulin levels are they still useful in the survey of inflammatory diseases when ESR can be easily determined?

The authors have determined systolic time intervals with carotid arterial Doppler system in a group of 113 healthy subjects. These systolic time intervals, were independent of age but strongly influenced by heart rate, and highly significant correlated with phonocardiographic and carotid arterial pulse tracings, according to the method described by Weissler. However Doppler index, no significantly correlated with heart rate, seems to us a better assessment of left ventricular performance than Weissler index. New reports on the hemodynamic determinants in healthy subjects and in patient with chronic heart failure are necessary.

Medical diagnosis assistance is described in terms of step by step logical reasoning methods. Boolean functions, possibly connected with phi-fuzzy functions, and a theorem proving algorithm may be used at each step. The choice merely depends on the accuracy of diagnosis at a given step. Numerical results based on a study of patients with thyroid diseases are presented.

This paper presents Sphinx, an expert system for computer-aided diagnosis in diabetes therapeutic. This interactive program makes logic deductions, comprehensible for users and it is not necessary for them to know artificial intelligence methodology. An improvement of the first results is possible and necessary, but the reliability of the advice already expressed by the system makes it useful as a future physician's implement.

After reviewing some of the elements that permit a clearer understanding of what characterizes the "expert systems" approach, representation of medical concepts, symbolic manipulation rather than numeric calculation, causal reasoning, etc., this paper will try to deal with some of the most noteworthy developments in medical decision aid, teaching, research, before discussing some problems raised by the evaluation of expert systems in medicine.

Quantitative analyses of the total phenols (glucosides and aglycones and phenylalanine ammonia lyase (PAL) activity were determined separately in bud scales and the leaf primordia of dormant buds (apical, subapical and basal) of Fagus sylvatica L, until bud burst. In all the leaf primordia, the phenol and glucoside contents did not change substantially from November to March. From dormancy break to bud burst, phenols and glucosides accumulated in the subapical and basal buds. PAL activity, after a drop at the inception of dormancy, followed a trend similar to that of the total phenol content during dormancy. After dormancy break, the PAL activity of the apical bud was higher than that of the subapical and basal buds. During this period several differences were observed between PAL activity and phenolic content along the branch. No aglyeortes were detected during dormancy (except small quantities in the subapical buds). However, small amounts were detected in all three bud types after dormancy break. On the other hand, in the bud scales during the winter total phenols per bud, glucosides and PAL activity values (except in the apical buds) show a slight decrease. After dormancy break, PAL activity disappeared and aglycone levels increased slightly. At the same time it was not possible to determine any clear net variation in the levels of phenols and glucosides. It seems, therefore, that the inception and maintenance of dormancy in F. sylvatica buds buds cannot be correlated to the total phenolic pool and PAL activity in leaf primordia, while some kind of correlation seems to occur in the case of bud scales.