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PubMed1995

Practice guidelines and healthcare telematics: towards an alliance.

This chapter reviews the motives behind the promotion, development and application of practice guidelines, defined as "systematically developed statements to assist practitioner and patient decisions about appropriate health care for specific clinical circumstances'. It surveys the state of progress and future prospects for telematics applications in this area, and reports the action points recommended by the 1994 AIM Conference. There exists significant evidence that use of guidelines can improve healthcare process and outcome, and that computerised aids assist this effect, they may also enhance the potential uses of guidelines and protocols for audit, resource management and shared care. A standard generic model for computerised representation of guidelines as knowledge bases in a common format has been proposed and may be a key factor in future progress. The development of computerised patient records of adequate scope and quality is generally recognised as an essential condition for computer-aided guideline use. Support for development, dissemination and application of healthcare guidelines and use has emerged, notably through the AIM EPISTOL study, as a feasible and useful application area of medical knowledge-based systems. It is essential that telematics developments in this field are grounded in an understanding of the healthcare practices to which guidelines are being applied, and of the changes in practice which guideline use may entail.

Artificial Intelligence↗

PubMed1997

Evaluation of automatically learned intelligent alarm systems.

In this contribution it is investigated whether a combination of mathematical simulation and inductive machine learning can replace the usual knowledge elicitation techniques. To test this a domain was selected for which knowledge based systems had a high performance: intelligent alarm systems. A mathematical model of a breathing circuit and ventilated patient was implemented in PSpice. Airway pressure, gas flows and CO2 concentration were simulated with this model, during normal functioning of the breathing circuit and during several mishaps, for a wide range of simulated patients. With an inductive machine learning program, classification trees were created from the simulated patient data. The classification trees described each breathing circuit mishap in terms of changes in signal feature values with respect to the normal situation and were implemented as alarm system knowledge bases. The alarm systems were tested with data measured at 17 mechanically ventilated animals. During ventilation of the animals several mishaps were introduced. For each animal, 93-100% of all mishaps could be detected correctly by the alarm systems. The false alarm rate ranged on average from one false alarm per h to one false alarm every 2.5 h. It was concluded that the suggested approach to knowledge elicitation was successful.

Animals↗

PubMedDate not supplied

Spec2D: a structure elucidation system based on 1H NMR and H-H COSY spectra in organic chemistry.

A system for structure elucidation based on proton NMR spectra has been developed. The system, named Spec2D (system for spectra from 2D-NMR), incorporates 1H NMR and H-H correlation spectroscopy (COSY) spectral information obtained from 2D-NMR experiments. 2D-NMR is important for the structure elucidation because it provides information about the relationships among differently situated protons in the structures of unknown compounds. The system uses the concepts of molecular graphs. The improved representation of substructures as well as several novel algorithms for structure generation have been devised to solve the combinatorial problem and to reduce the processing time. Spec2D consists of a knowledge base, an analysis module, and a candidate structure generator module. Spec2D proposes candidate structures from only 1H NMR and H-H COSY spectral information of an unknown compound without any 13C NMR spectral or structural information, such as molecular formulas. Spec2D has the capability to propose the "new" structure of an unknown compound, if the corresponding substructures are included in the knowledge base.

Journal Article↗

PubMed2002

GeneTests-GeneClinics: genetic testing information for a growing audience.

The development and usage of two companion NIH-funded genetic testing information databases, GeneTests (www.genetests.org) and GeneClinics (www.geneclinics.org), now merged into one web site, reflect the steadily increasing use of genetic testing and the expanding audience for genetic testing information. Established in 1993 as Helix, a genetics laboratory directory of approximately 110 listings, GeneTests has grown into a database of over 900 tests for inherited diseases, a directory of over 500 international laboratories, a directory of over 1,000 U.S. and international genetics clinics, and a resource for educational/teaching materials and reports of summary genetic test data. GeneClinics, founded in 1997 as an expert-authored, peer-reviewed, disease-specific knowledge base relating genetic testing to patient care, has grown steadily, now containing over 130 expert-authored, peer-reviewed full-text entries relating genetic testing information to diagnosis, management, and genetic counseling of specific inherited diseases. In spring 2001 the two databases were merged and in October 2001 the two web sites were merged for the purpose of seamless navigation into the GeneTests-GeneClinics site (www.genetests.org or www.geneclinics.org); the GeneClinics knowledge base was renamed "GeneReviews" to avoid confusion with the U.S. and international clinic directories. As genetic testing has moved steadily out of research venues and into routine medical practice, the user audience for these databases has become international and expansive and includes healthcare providers, patients, educators, policy makers, and the media. The use of these combined resources has grown to approximately 3,200 visits/day.

Databases, Genetic↗

PubMed1989

The diagnostic pattern in histopathology.

Defining in precise detail the diagnostic clues used by histopathologists to arrive at a diagnosis is a difficult process; however, better analytic understanding of this process is a prerequisite for the design of diagnostic expert systems. Such systems offer the potential for consistency and setting standards in the diagnostic evaluation of difficult situations. Diagnostic clues as offered by the image represent two-dimensional information. Their description is entered into the knowledge base of an aspect system, however, in the form of a description, which is one-dimensional. Preserving all of the two-dimensional dependence structure in this conversion is a fundamental problem. Use of the description to generate simulated imagery tests whether or not the two-dimensional dependence structure of a given tissue architecture has been adequately represented in the analytic description. This analytic description would then be entered into the knowledge base of an expert system.

Communication↗

PubMedDate not supplied

Comparing generalist and specialty care: discrepancies, deficiencies, and excesses.

Policymakers, managed care organizations, medical educators, and the general public are showing an increasing interest in the amount and quality of care provided by generalists and subspecialists. This article reviews studies comparing the knowledge base of and quality of care provided by these 2 groups of physicians. English-language articles were identified through MEDLINE (1966-present) using the following keywords: generalist, generalism, (sub)specialist, (sub)specialty, (sub)specialization, consultation, referral, and quality of care, and through the bibliographies of these citations. All studies were evaluated. With respect to quality of care, only American studies were chosen. Data quality was assessed by me. Evidence is strongest that the knowledge base and quality of care provided by specialists exceeds those of generalists for certain conditions such as myocardial infarction, depression, and acquired immunodeficiency syndrome. Differences in many other areas are multifactorial, and often a function of study design or patient selection. The differences, however, are not as striking or important to the health of the public at large as those deficiencies in disease management, preventive care, and health maintenance that are common to all physicians. Furthermore, overuse of diagnostic and therapeutic modalities by certain specialists leads to increased costs with either no benefit or added risks to patients. The quality and coordination of care provided by generalists and specialists may be improved through changes in education and training, via quality improvement methods of providing patient care, and by increasing visit length and optimizing use of referrals and strategies for generalist-specialist comanagement. Further study of these areas is warranted and should concentrate on outcomes.

Family Practice↗

PubMed1993

The Arden syntax for medical logic modules.

The Arden Syntax for sharing medical knowledge bases is described. Its current focus is on knowledge that is represented as a set of independent modules that can provide therapeutic suggestions, alerts, diagnosis scores, etc. The syntax is based largely upon HELP and the Regenstrief Medical Record System. Each module, called a Medical Logic Module or MLM, is made of slots grouped into maintenance, library, and knowledge categories. The syntax has provisions for querying a clinical database and representing time. Several clinical information systems were analyzed and appear to be compatible with the syntax. The syntax has been tested for syntactic ambiguities using the tools lex and yacc. Seventeen institutions are currently in the process of adopting the Arden Syntax for their decision-support systems. A subcommittee of ASTM has been formed to develop standards for sharing medical knowledge bases. The Arden Syntax has been published by ASTM as a initial standard for sharing medical knowledge.

Artificial Intelligence↗

PubMed2004

Trial bank publishing: phase I results.

BACKGROUND: Randomized clinical trials (RCTs) are an important source of evidence for clinical practice, but finding and applying RCT reports to care is time consuming. Publishing RCTs directly into machine-understandable "trial banks" may allow computers to deliver RCT evidence more selectively and effectively to clinicians. METHODS: Authors of eligible RCTs published in JAMA or the Annals of Internal Medicine between January 2002 and July 2003 were invited to co-publish their trial in RCT Bank, an electronic knowledge base containing details of trial design, execution, and summary results. Trial bank staff used Bank-a-Trial, a web-based trial-bank entry tool, to enter information from the manuscript into RCT Bank, obtaining additional information as necessary from the authors. RESULTS: The author participation rate rose from 38% to 76% after the first co-published trial was available as an example. Seven diverse RCTs are now co-published, with 14 in progress. CONCLUSIONS: We have demonstrated proof of concept for co-publishing RCTs with leading journals into a structured knowledge base. Phase II of trial bank publishing will introduce direct author submission to RCT Bank.

Databases as Topic↗

PubMed2002

MIPS Arabidopsis thaliana Database (MAtDB): an integrated biological knowledge resource based on the first complete plant genome.

Arabidopsis thaliana is the first plant for which the complete genome has been sequenced and published. Annotation of complex eukaryotic genomes requires more than the assignment of genetic elements to the sequence. Besides completing the list of genes, we need to discover their cellular roles, their regulation and their interactions in order to understand the workings of the whole plant. The MIPS Arabidopsis thaliana Database (MAtDB; http://mips.gsf.de/proj/thal/db) started out as a repository for genome sequence data in the European Scientists Sequencing Arabidopsis (ESSA) project and the Arabidopsis Genome Initiative. Our aim is to transform MAtDB into an integrated biological knowledge resource by integrating diverse data, tools, query and visualization capabilities and by creating a comprehensive resource for Arabidopsis as a reference model for other species, including crop plants.

Arabidopsis↗

PubMedDate not supplied

Strategies to enhance problem solving.

The ability to make high-level decisions based on a strong knowledge base and effective problem-solving strategies is an expected behavior of the professional nurse. The author discusses current knowledge of problem-solving components and teaching strategies as well as promising new computer strategies that are applicable to nursing education and practice.

Cognition↗

PubMed1995

Quality development based on informatics in health care: steps in the Danish national strategy illustrated by four cases.

The first step for quality development is identification of the quality problem. This should be followed by a set up of criteria and standards and relevant data should be collected to perform quality assessment. The quality-level is evaluated and in cases with non-satisfying results, the problem(s) should be identified and the process repeated [1]. Identification of the best results for continuous quality improvement and professional self-assessment is part of the process [1]. Decentralization of the whole quality development process is an aim. The Ministry of Health is politically responsible for the process and the National Board of Health is responsible for the implementation of the process at the national level. To support continuous quality development, three bills were passed in the government in 1992: 1) Free choice of hospital for the patients; 2) Appropriate local and regional distribution of specialized functions, to ensure optimal treatment of rare and complicated diseases; 3) Coordinated planning and organization of the health services. The strategy for quality development illustrated by four cases. Four projects were identified to illustrate steps in the national strategy for quality development. PROBLEM IDENTIFICATION. ESTEEM [2,3]: Using knowledge-based systems for interpretation of EMG (electromyography) in different laboratories disclosed great variations in clinical usability. The variations could be explained by different examination techniques, test planning protocols, and diagnostic criteria. It was concluded that the use of a EMG-knowledge based system disclosed great problems for standardization of procedures dependent on EMG measurements. QUALITY ASSESSMENT. Hip fracture quality project [unpublished data]: The assumption for the study was that early and active rehabilitation after hip fracture would promote the ability of the patients to cope with activities of daily living (ADL) and prevent development of complications. About 85% of the patients were expected to be able to go home on the 12th day, but this was the case for only 56% of the patients. It was concluded that the pre-set standard was not achieved and that the post-operative care was carried out in an ineffective way. QUALITY IMPROVEMENT. Laboratory quality project [4]: Quality control assessment procedures have been implemented for years in hospital laboratories. The aim of the study was to evaluate the size of analytical bias between two local hospital laboratories using the same reference intervals. The results showed that only a few of the routine analyses meet the goals for acceptance of general reference intervals in a geographical area. The problems were reflected in the quality assessment results but, nevertheless, no action seems to have been taken to minimize the bias. It is concluded that interpretation of quality control data is a great problem. QUALITY MONITORING AND EVALUATION. National databases for health care quality [5]: Principles for development, implementation, and use of national databases has been worked out by The National Board of Health. Clinical departments will get a tool to monitor and improve the daily working routines. National databases for clinical monitoring exist for vascular surgery, laparoscopic surgery, treatment of breast cancer, and surgery for hip fractures.

Denmark↗

PubMedDate not supplied

Webifying a patient interview support application.

This paper reports on the software engineering challenges, and resultant benefits experienced, in porting an interactive, knowledge-based system from Microsoft Windows to the World Wide Web for evaluation purposes. The Patients Interview Support Application (PISA) is a program intended for operation by a non-expert clerk to interview an ambulatory primary care patient. The PISA code had to be re-written substantially to address the 'connectionless' nature of Web dialog and to work in terms of dynamically generated HTML forms; however, it was possible to avoid any revision of the central knowledge-base or inference engine. The resultant Web environment attracted thought-provoking and detailed feedback from users, indicating that significant attention can be obtained from the global community by mounting an interactive system on the Web. Specific enhancements to the PISA's artificial intelligence are suggested by user reaction. A future global health informatics 'marketplace' with a multidue of Web-based system components available for composition of health information systems is envisioned.

Artificial Intelligence↗

PubMed1987

Memory development and neurophysiology: accomplishments and limitations.

The review of Teyler and Fountain offers developmental psychologists an update on the status of neurophysiological theorizing and findings related to memory and learning. Recent findings of LTP and of localization of different types of memory in different brain areas have potential for enriching our understanding of memory development. However, we note several limitations in Teyler and Fountain's presentation in that they do not: distinguish between learning and memory, nor between storage and retrieval; address the role of knowledge-based or top-down influences in memory and learning; employ concepts that can accommodate such developmental phenomena as stages in the hierarchical reorganization of memory. We conclude that even when the age-old search for the "engram" is accomplished, these issues will remain, and that different levels of neural modeling will be required to accommodate them. It is important for developmental psychologists and neuroscientists to maintain communication for the purpose of mutual refinement of models as their knowledge bases continue to grow.

Animals↗

PubMed1998

What should the Z-score of native protein structures be?

The Z-score of a protein is defined as the energy separation between the native fold and the average of an ensemble of misfolds in the units of the standard deviation of the ensemble. The Z-score is often used as a way of testing the knowledge-based potentials for their ability to recognize the native fold from other alternatives. However, it is not known what range of values the Z-scores should have if one had a correct potential. Here, we offer an estimate of Z-scores extracted from calorimetric measurements of proteins. The energies obtained from these experimental data are compared with those from computer simulations of a lattice model protein. It is suggested that the Z-scores calculated from different knowledge-based potentials are generally too small in comparison with the experimental values.

Models, Chemical↗

PubMed1998

A pragmatic implementation of medical temporal reasoning for clinical medicine.

In most development tools for knowledge-based systems object-property-value-triples are the basic ontological representation. We have extended this approach for temporal reasoning by replacing the values with time-objects. A time-object is a combination of a value with a time-point or a time-interval. By preserving the object-property-value-triples basic artificial intelligence techniques can be applied without modifications in the temporal case. The greater complexity of temporal inferences is compensated by a blackboard control architecture enabling small knowledge-sources. The control of the strategic reasoning is in accordance with the select and test model. A prototype of a knowledge-based advisor for the acute radiation syndrome has been implemented and partially evaluated. Due to the affected proliferative tissues it is a strongly time-oriented medical domain.

Acute Disease↗

PubMed1992

Structure-activity relationships for carcinogens with different modes of action.

The application of structure-activity concepts to the elucidation of the action of chemical carcinogens may proceed by two approaches: the hypothesis and the knowledge-based approaches. The former, exemplified by the 'structural alerts' devised by Ashby and associates, derives from the recognition of the electrophilic nature of carcinogens that damage DNA. The latter approach does not assume an a priori mechanism of action but derives information from the establishment of relationships between structural features and carcinogenicity. Indeed, the 'structural alerts' of Ashby et al. are recognized by such an approach; however, if structural features are associated with the activity of 'nongenotoxic' carcinogens, they would also be recognized by the knowledge-based approach. Obviously, the recognition of new (nonelectrophilic) structural features associated with carcinogenicity will lead to testable hypotheses.

Carcinogens↗

PubMed2004

Epidemiology: quo vadis?

In our etiologic research, we epidemiologists need to leave behind the concepts of 'cohort' study and 'case-control' study and adopt that of the etiologic study as the singular substitute for these. We then need to realize that the etiologic study is well suited to be viewed as paradigmal for intervention studies. We finally need to become serious about object design before methods design in both etiologic and intervention research. Once these developments have occurred, we'll be ready for truly meaningful research to advance the knowledge base of both types of causality-oriented 'gnosis' in the practice of clinical medicine, etiognosis and intervention-prognosis; and descriptive-prognostic study we'll see as inherent in any intervention-prognostic study. As for diagnostic research, then, we need to come to see it as nothing but a special case of our familiar descriptive prevalence research. Because of this readily attainable theoretical readiness peculiar to us research epidemiologists, and for other reasons besides, only we can assume the central role in the production of the knowledge base for scientific medicine. We consequently have the obligation to assume this larger and higher, meta-epidemiologic mission--and some even higher ones besides.

Causality↗

PubMedDate not supplied

Automated measurement of single and total lung volume from CT.

PURPOSE: The goal of this work was to develop an automated method for calculating single (SLV) and total (TLV) lung volumes from CT images. METHOD: Patients underwent volumetric CT scanning through the entire chest in a single breath-hold, as well as pulmonary function tests. An automated, knowledge-based system was developed to segment the lungs in the CT images. Image-processing routines were used to extract sets of voxels from the image data that were identified by matching them to anatomical objects defined in a model. SLV and TLV were calculated by summing included voxels. RESULTS: For 43 patients analyzed, TLV from CT and total lung capacity from body plethysmography were strongly correlated (r = 0.90). On average, the CT-derived volume of the left lung accounted for 47.2% of the total. CONCLUSION: A knowledge-based approach to segmentation of the lungs in CT can be used to automatically estimate SLV and TLV.

Artificial Intelligence↗