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PubMed2002

Dental concepts in the Unified Medical Language System.

OBJECTIVE: Currently, no comprehensive, controlled vocabulary for dentistry is available. The objective of this study was to determine how well the Unified Medical Language System, the largest repository of concepts and terms in biomedicine, represents dental concepts. METHOD AND MATERIALS: The dental subset of concepts was extracted from Unified Medical Language System using the software program APEX (APplication for the EXtraction of domain-specific concepts). The relationships contained in the Unified Medical Language System Metathesaurus were used to locate the concepts related to 12 seed terms. The Encyclopédie Médico-Chirurgicale (513 dental terms) and the Diagnostic Codes developed by Leake et al (124 terms) were compared to the dental subset. Terms were classified as exact match, related term, or no match. The resultant matching characteristics were compared to those determined by the National Library of Medicine/Agency for Health Care Policy and Research Large Scale Vocabulary Test. RESULTS: The dental subset of Unified Medical Language System contained 948 concepts. The Encyclopédie Médico-Chirurgicale and the Diagnostic Codes exhibited similar matching characteristics for exact match (61.6% and 58.9%, respectively) and related term (38.0% and 32.2%, respectively). For no match, the matching frequencies were significantly different (P < .001). CONCLUSION: The Unified Medical Language System may be a comprehensive source of terms suitable for various representation requirements in dentistry.

Chi-Square Distribution↗
PubMed1992

[Cost-benefit analysis of a new treatment concept in patients with indwelling catheters].

An earlier and a new treatment concept for patients equipped with long-term indwelling bladder catheters were compared with regard to cost, expenditure of time, and equipment in a retrospective study involving 58 patients treated by the earlier concept and 60 treated by the new one. The new concept dispensed with the need for bladder irrigation and routine replacement of the indwelling catheters. Under the earlier concept, 18 indwelling catheter replacements and 53 bladder irrigations were required per patient and year during the years 1979/80. This compares with 6 indwelling catheter replacements and 0.05 bladder irrigations per patient and year for the years 1989/90 under the new concept. The use of analgesics and spasmolytics fell from 55 to 21 units per patient per year. Significantly fewer urinalyses were performed during 1989/90. The use of antibiotics remained unchanged. When compared with the earlier one, the new concept for the management of patients with indwelling catheters provides savings of 1265 minutes (21 hours) of nursing time and sFr. 405 for equipment per patient per year. Applied to our geriatric hospital (120 beds, 80 nursing staff), this translates into annual savings of one full nursing post and sFr. 34,000 for equipment.

Aged↗
PubMedDate not supplied

Seasonal variation in adolescent conceptions, induced abortions, and late initiation of prenatal care.

The monthly distribution of conceptions among adolescents and the proportion of adolescent pregnancies that are voluntarily terminated by induced abortion by month of conception are the objects of this study. Additionally, seasonal variations in the timing of initiation of prenatal care services by adolescents are investigated. Vital records files of single live births, fetal deaths, and induced terminations of pregnancy to residents in the State of South Carolina, 1979-86, were aggregated to estimate conceptions. There was a significant difference between adolescents and adults in the monthly distribution of conceptions. The peak month of adolescent conceptions coincided with the end of the school year. Pregnancies of adolescents occurring at this time further demonstrated later access of prenatal care services than conceptions occurring at other times of the year, most notably during the school term. These findings suggest that there is considerable opportunity for improving the availability of reproductive health care services for adolescents. The results specifically suggest the potential benefit of increasing adolescent pregnancy prevention efforts prior to high-risk events and increasing the availability of and access to health care and counseling services to adolescents during the school recess months of the summer.

Abortion, Induced↗
PubMed2001

Different underlying mechanisms for deficits in concept formation in dementia.

We investigated the different mechanisms that may underlie deficits in verbal concept formation among patients with Alzheimer's disease (AD) and ischaemic vascular dementia (IVD) associated with periventricular and deep white matter alterations. Concept formation was assessed with the WAIS-R Similarities subtest (SIM). Two types of errors were re-coded from the 0-point responses as scored by the WAIS-R manual. In set errors (e.g., dog-lion "they're alive") were coded when patients reported a very vague superordinate concept for the word pair. Out of set responses (e.g., dog-lion "the lion roars and the dog barks") were coded when a response was clearly out of mental set, i.e., when participants were unable to provide a superordinate concept for the word pair. Between-group comparisons demonstrated no difference in SIM test performance according to the scoring system described in the WAIS-R manual. Nonetheless, AD patients produced a greater proportion of in set errors, while IVD patients produced a greater proportion of out of set errors. Out of set errors were highly associated with measures of executive function, while in set errors were associated with measures related to delayed recognition memory and semantic intrusion errors. We conclude that the underlying deficits that contribute to poor concept formation differ between AD and IVD patients. In IVD impaired concept formation is related to deficits in the executive systems necessary to monitor responses and sustain mental set. In AD, by contrast, the deficit appears to be secondary to impaired verbal response selection.

Journal Article↗
PubMed2003

A novel view on information content of concepts in extremely large ontologies.

Semantic distance and semantic similarity are two important information retrieval measures used in word sense disambiguation as well as for the assessment of how relevant concepts are with respect to the documents in which they are found. A variety of calculation methods have been proposed in the literature, whereby methods taking into account the information content of an individual concept outperform those that don't. In this paper, we present a novel recursive approach to calculate a concept's information content based on the information content of the concepts to which it relates. The method is applicable to extremely large ontologies containing several million concepts and relationships amongst them. It is shown that a concept's information content as calculated by this method provides additional information with respect to an ontology that cannot be approximated by hierarchical edge-counting or human insight. In addition, it is suggested that the method can be used for quality control within large ontologies.

Algorithms↗
PubMed2003

IndexFinder: a method of extracting key concepts from clinical texts for indexing.

Extracting key concepts from clinical texts for indexing is an important task in implementing a medical digital library. Several methods are proposed for mapping free text into standard terms defined by the Unified Medical Language System (UMLS). For example, natural language processing techniques are used to map identified noun phrases into concepts. They are, however, not appropriate for real time applications. Therefore, in this paper, we present a new algorithm for generating all valid UMLS concepts by permuting the set of words in the input text and then filtering out the irrelevant concepts via syntactic and semantic filtering. We have implemented the algorithm as a web-based service that provides a search interface for researchers and computer programs. Our preliminary experiment shows that the algorithm is effective at discovering relevant UMLS concepts while achieving a throughput of 43K bytes of text per second. The tool can extract key concepts from clinical texts for indexing.

Abstracting and Indexing↗
PubMed2005

Using the Rasch model to validate stages of understanding the energy concept.

In recent years, there have been efforts to bridge science education with developmental psychology to develop theories on students developing understanding of science concepts from elementary to high school and beyond. The present study intends to test one such theory on students developing understanding of the energy concept. The theory states that students develop understanding of the energy concept by going through the following qualitatively distinct stages: (a) energy as activity/work; (b) energy as sources/forms, (c) energy transfer, (d) energy degradation, and (e) energy conservation. Three classes, one each from 4th grade, 8th grade, and high school physics class (grades 10, 11, and 12), completed a performance assessment. Students' performances were scored based on three traits of energy understanding: attention capacity, qualitative relations, and quantitative relations; each of the traits was defined into five hierarchical levels consistent with the five stages of understanding the energy concept. The Many-Facet Rasch Measurement (MFRM) model was used to analyze the effects of rater scoring severity, students' stages of energy understanding (theta), and difficulties of energy understanding traits. Results show that there was a discontinuity among the stages of understanding the energy concept, supporting the theory on students developing the understanding of the energy concept.

Adolescent↗
PubMed2006

Reification of abstract concepts to improve comprehension using interactive virtual environments and a knowledge-based design: a renal physiology model.

Several abstract concepts in medical education are difficult to teach and comprehend. In order to address this challenge, we have been applying the approach of reification of abstract concepts using interactive virtual environments and a knowledge-based design. Reification is the process of making abstract concepts and events, beyond the realm of direct human experience, concrete and accessible to teachers and learners. Entering virtual worlds and simulations not otherwise easily accessible provides an opportunity to create, study, and evaluate the emergence of knowledge and comprehension from the direct interaction of learners with otherwise complex abstract ideas and principles by bringing them to life. Using a knowledge-based design process and appropriate subject matter experts, knowledge structure methods are applied in order to prioritize, characterize important relationships, and create a concept map that can be integrated into the reified models that are subsequently developed. Applying these principles, our interdisciplinary team has been developing a reified model of the nephron into which important physiologic functions can be integrated and rendered into a three dimensional virtual environment called Flatland, a virtual environments development software tool, within which a learners can interact using off-the-shelf hardware. The nephron model can be driven dynamically by a rules-based artificial intelligence engine, applying the rules and concepts developed in conjunction with the subject matter experts. In the future, the nephron model can be used to interactively demonstrate a number of physiologic principles or a variety of pathological processes that may be difficult to teach and understand. In addition, this approach to reification can be applied to a host of other physiologic and pathological concepts in other systems. These methods will require further evaluation to determine their impact and role in learning.

Comprehension↗
PubMed1991

Remarks on the use of some basic epidemiological concepts in dentistry.

Scientific concepts do not emerge and develop in a vacuum but in the context in which they are used. Many concepts in epidemiology have their roots in destinal general infectious diseases that occur only once in one's life. The use of many epidemiological concepts varies greatly, even within medicine. Diseases such as dental caries, gingivitis and periodontitis cannot easily be described using concepts such as prevalence, incidence or risk, without creating confusion. The concepts sensitivity, specificity and positive and negative predictive value can also easily lead to misunderstandings. Clarifications regarding the use of these concepts in dentistry are suggested.

Dentistry↗
PubMed1990

Effect of ultrasound monitoring of follicular growth on the conception rate. A clinical study.

Periovulatory ultrasonography (POUS) was performed on 59 anovulatory women over 523 treatment cycles. Follicular development was stimulated with either clomiphene citrate (CC) or human menopausal gonadotropin (hMG). Thirty-one pregnancies were induced; 23 went to term. Three factors were considered in evaluating the incidence of conception: the patient's age, drug use and the presence or absence of POUS. There was no evidence that the pregnancy rate after POUS differed from that without it (estimated conception rate ratio = 1.2:1, P = .76). Similarly, conceptus viability was not demonstrably different whether POUS was used or not (P = 1.00). However, the data show a strong advantage of hMG over CC in achieving conception (estimated conception rate ratio = 5.85, P less than .0001) and no disadvantage in conceptus viability (P = 1.00). The data also suggest that in women less than 30 years of age with polycystic ovaries, ovulation induction is easier to achieve and the conception rate higher than in older women. There was no evidence that POUS decreased the conception rate or increased fetal wastage.

Adult↗
PubMed1990

The dependence syndrome concept as applied to alcohol and other substances of abuse.

The dependence syndrome concept has been defined by both behavioral and biological changes that occur with excessive substance use. Originally developed for alcohol, this concept was adopted for diagnosing dependence on other substances of abuse, although little research had been done to test its validity for other drugs. This chapter addresses the validity of the dependence concept across drug classes in the following ways. First, we compare the dependence items for three different drugs, alcohol, opiates, and cocaine, in measures of internal consistency. Second, biological items are correlated with behavioral items to assess the usefulness of defining dependence by both biological and behavioral criteria. Finally, we draw upon ideas developed in motivational theory and apply these to the dependence syndrome concept. These analyses, while supporting the validity of the concept, lead to suggestions for refining the concept of dependence.

Alcoholism↗
PubMed1990

Conception delay after oral contraceptive use: the effect of estrogen dose.

A significant delay was observed in conception among 248 former oral contraceptive (OC) users compared with women discontinuing other methods of contraception (n = 1,365). The mean time to conception was 5.88 cycles (95% confidence interval [CI] 5.38, 6.38) for former OC users and 3.64 cycles (95% CI 3.49, 3.79) after other contraceptives. Women discontinuing OCs with higher doses of estrogen (greater than or equal to 50 micrograms) had greater conception delays than those on lower estrogen doses who, in turn, had longer delays than other method users. Oral contraceptive use was associated with significant reductions in conception for each of the first six cycles after discontinuation. This study provides further evidence for a direct effect of oral contraception on delayed conception, suggests that the delay lasts longer than previously thought, and finds that the probability of conception after OC discontinuation depends on the estrogen dose of the OC.

Adolescent↗
PubMed1990

[The concept of man in nursing education: evaluation of the students' answers to the exam questions in nursing].

The purpose of the study was to describe the concept of man in nursing education. The data consisted of the nursing students' answers to the summative exam questions in seven courses in nursing. The total number of answers in the study was 202. The data was analyzed by the method of content analysis. Four dimensions of the concept of man were formed on the basis of the theoretical background: the holistic concept of man, the reduced concept of man, man as an active subject, man as a passive object. From the answers 40% described man as a holistic, active subject and 30% as a reduced, passive object. Man as a holistic, passive object was identified in 16% of the answers and as a reduced, active subject in the rest. The holistic concept of man was expressed as a bio-psychosocial wholeness. The reduced concept meant that man was described mostly as a biological organism. The activity of man was described as concrete activity, man was not described as a decision maker.

Achievement↗
PubMed1986

Adams' closed-loop concept of learning and motor performance: its application in behavioural kinesiology and patients' education in rehabilitation.

The earlier attempts to explain the process of learning were briefly reviewed. The limitations of these attempts led to the origin of the closed-loop concept of learning and motor performance. The analogy between the concept and a closed-loop machine model was explained in order to substantiate the relevance of this concept in human performance. The reason for the choice of Adams' concept (amongst those of others) has been identified--its uniqueness in the definition of the perceptual trace and, more importantly, the role of the knowledge of result (KR) of a performance in the learning process. A synthetic review of some literature that discussed Adams' concept has also been done. Finally, this paper has revealed that Adams' closed-loop concept is very applicable to behavioural kinesiology and patients' education in rehabilitation. It is, therefore, hypothesized that a more specific model can be developed to explain the detail of the environmental and kinematic contingencies that are inherent in this application.

Feedback↗
PubMed1985

Children's concepts of illness: implications for health teaching.

Children's concepts develop through different stages from global and undifferentiated to concrete and abstract. In the concrete stage perceptual and physical attributes of a concept are dominant. In the abstract stage the essential mental and nonperceptual attributes of a concept are grasped. In general, children's concepts of illness shift with age from definitions based largely on feeling states to broader, more precise definitions that include specific diagnoses and psychosocial indicators of illness. The basis for determining if one is ill also shifts with age from reliance on external cues to reliance on internal body cues. Children's knowledge of specific illnesses increases markedly during the school-age years. It appears that their concepts of specific illnesses are a synthesis of real knowledge and imaginative distortions. Children's concepts of illness causation also develop through different stages from global and undifferentiated to concrete and abstract. School-age children tend to attribute illness causation to their own actions but with age illness is increasingly attributed to external causes. There is in the school-age years increasing differentiation between external and internal in explanations of illness causation with inclusion of means of internalization of the causal agent and intermediary steps between cause and effect. This trend continues in adolescence with description of the illness mechanism in terms of physiologic processes, internal organ, and malfunctions.

Adolescent↗
PubMed1983

Reflections on some relations between psychoanalytic concepts and psychoanalytic practice.

This paper adopts the standpoint that psychoanalytic theory has been in a state of continuous organic development from the beginning, with states of theoretical strain being generated with each new advance in theory. The meaning of concepts becomes stretched, and psychoanalysts develop implicit theories, concepts and definitions that differ from the 'official' or 'public' formulations. While flexible concepts play an important part in psychoanalytic theory, it should be accepted that each may have a number of dimensions of meaning, and that these dimensions may differ from one psychoanalyst to another. Research should be directed towards making explicit the implicit concepts of practising psychoanalysts, and it is suggested that this process will result in the accelerated development of psychoanalytic theory. The essentials of that theory must be those aspects which relate to the work the psychoanalyst has to do, and therefore its main emphasis needs to be clinical. In the second part of the paper, the expansion of the concept of transference with the introduction of defence analysis is discussed, with particular reference to the class of object-related defences, which involve some combination of identification and projection. It is argued that major changes in technical emphasis brought about the extension of the transference concept, which now has dimensions of meaning which differ from the official definition of the term. Finally, three areas among many in which there is a significant distance between theory and practice are discussed. The public and official theories relating to drives, conflict, and internal object-relationships and transference are discussed, and suggestions made in regard to possible developments which might lessen the gap between the public theories and the implicit private clinical formulations of the practising psychoanalyst.

Conflict, Psychological↗
PubMed1980

[Concept of polymerization and oligomerization in morphology].

The animal body consists of a large number of parts (organs, organoids, parts of organs etc.). This is reflected in names of different taxa including the words "poly" and "oligo" and has been laid into the bases of V.A. Dogiel's conception on polymerization and oligomerization. The least developed part of the conception dedicated to the hosts of organs is critically considered. The organs are divided into two principally different forms: diffuse hosts of similar organs and close hosts of similar elements in the same organ. A great importance of V.A. Dogiel's conception for foundation of a new section in morphology is demonstrated--the notion on hosts of organs. Failures in terminology and that in keeping the principle of homology together with ignoring the close hosts resulted in certain disadvantages of V.A. Dogiel's conception mentioned in the literature. Analysis of both forms mentioned above and that of their evolutional development helped to eradicate the disadvantages pointed above from V.A. Dogiel's conception. Biochemical terminology corresponding to biological tradition is the most suitable for V.A. Dogiel's conception. Besides hosts of organs, another components of the animal body are separate organs or parts of organs. Therefore, it is possible to divide all the animals according to their body structure into polymeres and heteromeres; this approach is also applicable in organs' anatomy.

Anatomy↗
PubMed1996

Event-time analysis of the effect of season of parturition, parity, and concurrent disease on parturition-to-conception interval in dairy cows.

OBJECTIVE: To quantify the effect of season of parturition, parity, and various diseases on time to conception. DESIGN: Event-time analysis (survival analysis). SAMPLE POPULATION: 44,450 cows delivering calves between September 1985 and September 1986, from 6,227 Ayrshire dairy herds in 80 Finnish communities. PROCEDURES: Primiparous and multiparous cows were analyzed in separate Cox proportional hazards models for postpartum days 56 to 120. Occurrence of 43 diseases or disorders was recorded; codes were condensed into 25 variables offered to each model. Season of parturition was categorized into spring, summer, and fall-winter; for multiparous cows, 3 categorical variables represented parity. Models controlled for 60-day milk and milk fat production, herd milk production, and community. For all observations, parturition-to-conception interval was plotted against calendar day of parturition. RESULTS: For multiparous cows, parturition in the spring or summer and being of parity 2 or 3-4 (vs older) increased the chance of conceiving; 10 diseases or disorders decreased this probability. Similarly, in the model for primiparae, parturition in spring or summer increased the probability of conception, and 6 disorders decreased it. Disorders that were detrimental in both models were anestrus, ovulatory dysfunction, other infertility, late metritis, and clinical ketosis. CONCLUSIONS: The effect of season on the parturition-to-conception interval was marked at this latitude. Parturition during late April, causing confluence of postpartum day 55 with the summer solstice, was associated with the shortest parturition-to-conception intervals. Ketosis was found to be an important factor in lengthening the parturition-to-conception interval, highlighting the effect of negative energy balance on postpartum restoration of reproductive function.

Animals↗