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Results for “Knowledge base”

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PubMed1997

Structuring clinical practice guidelines in a relational database model for decision support on the Internet.

The rapid proliferation of clinical practice guidelines (CPGs) has made computerization increasingly useful to clinicians. Computerization, however, requires transformation of the content and logic of each guideline into a computer-accessible form. In this project, we sought to use a relational database to construct a generalized guideline knowledge base for use with Internet-based decision support applications. We hypothesized that knowledge representation schemes could be developed to capture guideline content and logic within the constraints of a relational database model. In this paper we describe a database schema based on a relational model for computerizing CPGs using a hybrid of structured and procedural knowledge representation schemes. We developed and refined this model in the context of five diverse CPGs and found it accommodated all necessary representational requirements.

Algorithms↗

PubMed2001

Orthodontic treatment--yes or no? A difficult decision in some cases. A contribution to the discussion.

Reasons for orthodontic treatment are discussed on the basis of 1. evidence-based knowledge from the literature, 2. viewpoints based on clinical experience, 3. case presentations. Viewpoints regarding prophylactic aspects of orthodontic treatment in relation to oral health are critically evaluated. The clinically based experience that dentofacial esthetics is the main reason for most patients requesting orthodontic treatment is also well documented in the literature. Against this background, psychosocial aspects as an indication for orthodontic treatment deserve greater recognition.

Adolescent↗

PubMed2003

Transgenic tumor models for carcinogen identification: the heterozygous Trp53-deficient and RasH2 mouse lines.

Genetically altered mouse models (GAMM) for human cancers have been critical to the investigation and characterization of oncogene and tumor suppressor gene expression and function and the associated cancer phenotype. Similarly, several of the mouse models with defined genetic alterations have shown promise for identification of potential human carcinogens and investigation of mechanisms of carcinogen-gene interactions and tumorigenesis. In particular, both the B6.129N5-Trp53 mouse, heterozygous for a p53 null allele, and the CB6F1-RasH2 mouse, hemizygous for the human H-ras transgene, have been extensively investigated. Using 26-week exposure protocols at or approaching the maximum tolerated dose, the summary results to date indicate the potential for GAMM to identify and, possibly, classify chemicals of potential risk to humans using short-term carcinogenicity experiments. This IWGT session focused on: (1) the development of recommendations for genetic/molecular characterization required in animals, tissues, and tumors before and after treatment for identification of presumptive human carcinogens based on the current state of knowledge, (2) identification of data gaps in our current state of knowledge, and (3) development of recommendations for research strategies for further development of our knowledge base of these particular models. By optimization of protocols and identification of significant outcomes and responses to chemical exposure in appropriate short-term mechanism-based genetically altered rodent models, strategies for prevention and intervention may be developed and employed to the benefit of public health.

Animals↗

PubMed2000

Effectiveness of problem-based learning curricula: research and theory.

PURPOSE: This article provides a critical overview of problem-based learning (PBL), its effectiveness for knowledge acquisition and clinical performance, and the underlying educational theory. The focus of the paper is on (1) the credibility of claims (both empirical and theoretical) about the ties between PBL and educational outcomes and (2) the magnitude of the effects. METHOD: The author reviewed the medical education literature, starting with three reviews published in 1993 and moving on to research published from 1992 through 1998 in the primary sources for research in medical education. For each study the author wrote a summary, which included study design, outcome measures, effect sizes, and any other information relevant to the research conclusion. RESULTS AND CONCLUSION: The review of the literature revealed no convincing evidence that PBL improves knowledge base and clinical performance, at least not of the magnitude that would be expected given the resources required for a PBL curriculum. The results were considered in light of the educational theory that underlies PBL and its basic research. The author concludes that the ties between educational theory and research (both basic and applied) are loose at best.

Curriculum↗

PubMed1998

Formal pathology rotation during obstetrics and gynecology residency: is it beneficial?

BACKGROUND: Our objective was to assess the educational benefits of a formal pathology rotation during an obstetrics and gynecology residency program and to determine the utility of this information in clinical practice. METHODS: In this descriptive study, the benefits of a 2-month rotation in pathology for obstetrics and gynecology residents were analyzed. A computerized listing of surgical cases processed by each resident was sent to the obstetrics and gynecology program director. RESULTS: Our resident accessioned 5.4% of the total pathology cases processed each month. Reports from previous residents (over a 17-year period) and from program directors at the annual educational retreat indicate that such information was not relevant to our graduates in their clinical practice. CONCLUSIONS: A formal pathology rotation for obstetric residents can improve knowledge base, but the usefulness of this knowledge in clinical practice is dubious.

Curriculum↗

PubMed1998

Ovarian ultrasound image analysis: follicle segmentation.

Ovarian ultrasound is an effective tool in infertility treatment. Repeated measurements of the size and shape of follicles over several days are the primary means of evaluation by physicians. Currently, follicle wall segmentation is achieved by manual tracing which is time consuming and susceptible to inter-operator variation. An automated method for follicle wall segmentation is reported that uses a four-step process based on watershed segmentation and knowledge-based graph search algorithm which utilizes priori information about follicle structure for inner and outer wall detection. The automated technique was tested on 36 ultrasonographic images of women's ovaries. Validation against manually traced borders has shown good correlation of manually defined and computer-determined area measurements (R2 = 0.85 - 0.96). The border positioning errors were small: 0.63+/-0.36 mm for inner border and 0.67+/-0.41 mm for outer border detection. The use of watershed segmentation and graph search methods facilitates fast, accurate inner and outer border detection with minimal user-interaction.

Algorithms↗

PubMed1992

An exploratory study of the sources of influence on the clinical decisions of community nurses.

This paper reports a small exploratory study which identifies what community nurses consider to be the scope of their practice and the sources of influence on their clinical decisions. The study was stimulated by the emergence of the nurse prescribing initiative, which is likely to bring clinical decision making to the centre of professional debate. The study was carried out over a 5-month period and data were collected from 47 community nurses in four district health authorities. A qualitative method was employed and field work involved observation of 40 home visits and five nurse-run clinics, individual interviews and group discussions with the nurses, and scrutiny of nursing records. The data were content analysed and classified, and the categories were validated by practitioners. Findings suggest that although community nurses consider that a large proportion of their work requires a scientific basis, their practice is largely founded on experiential knowledge, and on the whole they are not positively disposed to research knowledge. The findings are discussed in the context of nurse prescribing. Questions are raised about the nature of a 'professional' knowledge base and the reclassification of scientific knowledge as nursing or experiential knowledge once it has diffused into practice.

Attitude of Health Personnel↗

PubMed2006

A computer-aided method to expedite the evaluation of prognosis for childhood acute lymphoblastic leukemia.

This study presented a fully-automated computer-aided method (scheme) to detect metaphase chromosomes depicted on microscopic digital images, count the total number of chromosomes in each metaphase cell, compute the DNA index, and correlate the results to the prognosis of childhood acute lymphoblastic leukemia (ALL). The computer scheme first uses image filtering, threshold, and labeling algorithms to segment and count the number of the suspicious "chromosome," and then computes a feature vector for each "detected chromosome." Based on these features, a knowledge-based classifier is used to eliminate those "non-chromosome" objects (i.e., inter-phase cells, stain debris, and other kinds of background noises). Due to the possible overlap of the chromosomes, a classification criterion was used to identify the overlapped chromosomes and adjust the initially counted number of the total chromosomes in each image. In this preliminary study with 60 testing images (depicting metaphase chromosome cells) acquired from three pediatric patients, the computer scheme generated results matched with the diagnostic results provided by the clinical cytogeneticists. The results demonstrated the feasibility or potential of using a computerized method to replace the tedious and the reader-dependent diagnostic methods commonly used in genetic laboratories to date.

Algorithms↗

PubMed2000

Ethical dilemmas in general hospitals: social workers' contribution to ethical decision-making.

Thirty-two hospital social workers, fourteen of them directors of social work services and eighteen direct practitioners, were interviewed about their perception of the factors influencing social workers' contribution to the resolution of ethical dilemmas in general hospitals in Israel. Findings revealed that while ethical decision-making in hospitals is an interdisciplinary process, social workers' contribution to the process is affected by rivalry between social workers and other members of the health team, personality differences, type of ward and the nature of the ethical dilemma. Participants of the study had quite a clear perception of their role and of the unique knowledge-base social work can offer, including knowledge of the individual and family life course, understanding and skills in coping with diseases, and systems thinking. In order to increase their influence in ethical decision-making, the hospital social workers felt they must put more effort into developing their relationships with the other professionals involved in ethical decision-making both by making themselves more indispensable and by making their contribution explicit through greater documentation of their activities. The findings also implied that in order to gain more power and be accepted as equal partners in multidisciplinary teams, hospital social workers should improve their communication skills when interacting with representatives of other heath care professions.

Decision Making↗

PubMed1995

Level of operator control and changes in heart rate variability during simulated flight maintenance.

The demands of dynamic monitoring and fault diagnosis for flight engineer trainees were examined in relation to changes in heart rate (HR) and two spectral analysis measures (midfrequency: 0.07-0.14 Hz; high frequency: 0.15-0.40 Hz) of heart rate variability (HRV). Eleven trainee flight engineers were studied, as part of their training and assessment, over three 3-h sessions in a cockpit simulator. During each session, faults and incidents programmed into the system had to be detected, diagnosed, and corrected. Electrocardiograms were taken, and each session was recorded on videotape. Work phases were classified from video analysis of flight maintenance activities, using Rasmussen's cognitive control taxonomy, into monitoring, routine (rule-based), and problem-solving (knowledge-based) phases. HR and HRV were found to be sensitive to different phases of the work environment. HRV was suppressed during the mentally demanding problem-solving mode of the level flight phase, but only for the midfrequency component. Elevated heart rate, in contrast, was associated with the more generally stressful takeoff and landing phases. The findings support both the use of HRV as a physiological index of mental effort and its value in operational contexts, and the value of ecologically derived methods of evaluating differences in work demands in complex systems.

Adult↗

PubMed1997

XBONE: a hybrid expert system for supporting diagnosis of bone diseases.

In this paper, XBONE, a hybrid medical expert system that supports diagnosis of bone diseases is presented. Diagnosis is based on various patient data and is performed in two stages. In the early stage, diagnosis is based on demographic and clinical data of the patient, whereas in the late stage it is mainly based on nuclear medicine image data. Knowledge is represented via an integrated formalism that combines production rules and the Adaline artificial neural unit. Each condition of a rule is assigned a number, called its significance factor, representing its significance in drawing the conclusion of the rule. This results in better representation, reduction of the knowledge base size and gives the system learning capabilities.

Bone Diseases↗

PubMed2000

Limiting harm in the ICU.

This year, the US Institute of Medicine has estimated that medical errors kill up to 98,000 Americans each year,1 a problem surpassing automobile fatalities. For patients on the medical ward, drug therapy is the primary intervention they are receiving yet medication errors occur in as many as 4% of inpatients.2 Although greater monitoring intensity and much lower nurse-patient ratios in the ICU may reduce the incidence of medication errors, the shear number if interventions dramatically increases the risk of error.3 Furthermore, the study by the Institute of Medicine only addressed a small part of the problem. The taxonomy of errors includes both "accidents" (skill-based errors) and intentional "mistakes" (knowledge-based and rule-based errors).2 Thus, the Institute of Medicine would not consider the proscribing of human growth hormone for cachexia an error unless the proscribed dose was not administered or it was given to the wrong patient. In the ICU, the risks associated with both kinds of errors are considerable. In this review we will focus on the second kind of errors and examine harms associated with the care of patients with sepsis.

Anesthesia↗

PubMed2000

Knowledge representation and tool support for critiquing clinical trial protocols.

The increasing complexities of clinical trials have led to increasing costs for investigators and organizations that author and administer those trials. The process of authoring a clinical trial protocol, the document that specifies the details of the study, is usually a manual task, and thus authors may introduce subtle errors in medical and procedural content. We have created a protocol inspection and critiquing tool (PICASSO) that evaluates the procedural aspects of a clinical trial protocol. To implement this tool, we developed a knowledge base for clinical trials that contains knowledge of the medical domain (diseases, drugs, lab tests, etc.) and of specific requirements for clinical trial protocols (eligibility criteria, patient treatments, and monitoring activities). We also developed a set of constraints, expressed in a formal language, that describe appropriate practices for authoring clinical trials. If a clinical trial designed with PICASSO violates any of these constraints, PICASSO generates a message to the user and a list of inconsistencies for each violated constraint. To test our methodology, we encoded portions of a hypothetical protocol and implemented designs consistent and inconsistent with known clinical trial practice. Our hope is that this methodology will be useful for standardizing new protocols and improving their quality.

Artificial Intelligence↗

PubMed2006

Design of a decision support system for chronic diseases coupling generic therapeutic algorithms with guideline-based specific rules.

Clinical Decision Support Systems (DSS) help improve health care quality. They usually incorporate an Execution Engine (EE), defined for each disease. We have designed, and present here, a generic execution engine, coupled with guideline-based disease specific rules stored in knowledge base (KB) as part of the prescription-critiquing mode of the ASTI project. This system was designed using two national guidelines for type 2 diabetes and hypertension. It takes into account the patient's clinical data, the tolerance and effectiveness of previous and current treatments and the physician's prescription made at the time. The functioning of the system has been speeded up and its maintenance made easier by indexing the KB rules according to the type of treatment they are linked to (e.g. monotherapy, etc.) and by classifying them into four categories. The EE's design formalizes generic therapeutic algorithms, leading to treatment options for cases of bad tolerance or insufficient effectiveness of the current treatment. Its applicability to other diseases was shown by applying it to dyslipidemia.

Algorithms↗

PubMed1995

An integrated system to represent and manage medical knowledge.

This paper describes an integrated system in Prolog that permits the creation of a personal Knowledge Base to express and formalize specialist knowledge in medicine. Formalisms used are production rules and frames. The integrated system is able to manage data and knowledge stored in a database built in M Technology (MUMPS).

AIDS-Related Opportunistic Infections↗

PubMedDate not supplied

Terminology support for development of sharable knowledge modules.

Lack of an agreed infrastructure for terminology is identified as one of the major barriers to interchange of knowledge modules and integration of knowledge bases with other clinical information systems. The goal of the GALEN project is to bridge this gap between different terminology systems through the construction of a terminology server, which is based on a rich conceptual model with mapping facilities to natural language expressions and coding schemas. The long term goal is to support communication between medical information systems. Arden Syntax is a standard format for the creation of knowledge modules, with sharability as one of the main objectives. Since Arden Syntax is based on a data-driven approach, the data items used need to be adapted to locally available terminology. The GALEN approach appears to be complementary to Arden Syntax and to the development of sharable knowledge modules. The major theme of this paper is utilization of the GALEN terminology server for knowledge module authoring. Two systems are presented, a knowledge base manager and a client to the terminology server, allowing the user to navigate in the semantic network and to import concept definitions and terms into the knowledge modules. The benefit of the terminology server, allowing the user to navigate in the semantic network and to import concept definitions and terms into the knowledge modules. The benefit of the terminology services is discussed.

Artificial Intelligence↗

PubMed2004

Evidence-based and intuition-based self-knowledge: an FMRI study.

Behavioral and neuropsychological studies have suggested multiple self-knowledge systems may exist (i.e., evidence-based and intuition-based self-knowledge); however, little is known about the nature of intuition-based self-knowledge. In a functional magnetic resonance imaging study, the neural correlates of intuition-based and evidence-based self-knowledge were investigated. Participants with high and low experience in different domains (soccer and acting) made self-descriptiveness judgments about words from each domain while being scanned. High-experience domain judgments produced activation in a network of neural structures called the X-system, involved in automatic social cognition, whereas low-experience domain judgments produced activations in a network called the C-system, involved in effortful social cognition and propositional thought. The affective and slow-changing nature of intuition-based self-knowledge is discussed.

Adult↗

PubMed1990

[Reflections on information management in clinical research].

Some considerations are made on the importance of clinical, information and its transcendence in medical research, as well as on the ethical value of a qualitatively correct data treatment. After describing by means of a bibliographical search, the present-day tendency towards knowledge based systems, there is offered a general overview of clinical information management, from data collection through study design and statistical assessment, up to the building of a knowledge data base.

Artificial Intelligence↗