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UMLS-based conceptual queries to biomedical information databases: an overview of the project ARIANE. Unified Medical Language System.

OBJECTIVE: The aim of the project ARIANE is to model and implement seamless, natural, and easy-to-use interfaces with various kinds of heterogeneous biomedical information databases. DESIGN: A conceptual model of some of the Unified Medical Language System (UMLS) knowledge sources has been developed to help end users to query information databases. A query is represented by a conceptual graph that translates the deep structure of an end-user's interest in a topic. A computational model exploits this conceptual model to build a query interactively represented as query graph. A query graph is then matched to the data graph built with data issued from each record of a database by means of a pattern-matching (projection) rule that applies to conceptual graphs. RESULTS: Prototypes have been implemented to test the feasibility of the model with different kinds of information databases. Three cases are studied: 1) information in records is structured according to the UMLS knowledge sources; 2) information is able to be structured without error in the frame of the UMLS knowledge; 3) information cannot be structured. In each case the pattern-matching is processed by the projection rule according to the structure of information that has been implemented in the databases. CONCLUSION: The conceptual graphs theory provides with a homogeneous and powerful formalism able to represent both concepts, instances of concepts in medical contexts, and associations by means of relationships, and to represent data at different levels of details. The conceptual-graphs formalism allows powerful capabilities to operate a semantic integration of information databases using the UMLS knowledge sources.

Databases as Topic

[School children's knowledge of, need for and use of contraception before and after the AIDS campaigns. Knowledge and sources of information].

The purpose of the present paper was to investigate the influence of the AIDS-campaigns on adolescents' knowledge of contraception and pregnancy and their sources of information. All pupils in their ninth school year in the municipality of Viborg answered an identical questionnaire in 1986 and 1993, dealing with the mentioned subjects. In 1986, 539 questionnaires were included, in 1993, 391. In 1986, sexually inexperienced boys had lesser knowledge than the rest. This could not be shown in 1993. Although their knowledge was not optimal, the pupils in 1993 answered better than the 1986-pupils. They had the same informational sources, but in 1993, the school was mentioned as an important source by nearly all. The mother, on the contrary, had decreasing importance as a source of information. Two thirds were generally satisfied by the sexual information given by the school. Experienced boys were significantly more often unsatisfied. It is concluded that the condom-orientated AIDS-campaigns have not in general decreased the knowledge of contraception and pregnancy among adolescents. Their knowledge is, however, not optimal. The school is extremely important as an informational source, especially if the importance of the parents decreases. This implies that fewer of those adolescents, who have left school, have adult support in dealing with sexual problems.

Acquired Immunodeficiency Syndrome

Centers for disease control and prevention lead guidelines: do pediatricians know them?

American Academy of Pediatrics (AAP) fellows responded to a questionnaire measuring knowledge of 1991 Centers for Disease Control and Prevention (CDC) guidelines. Generalists' scores on a knowledge scale were positively correlated with reporting CDC and AAP documents as knowledge sources, and negatively correlated with private practice, medical school as a knowledge source, and age. However, private practitioners who read AAP documents scored well.

Adult

Sex education and contraceptive methods: knowledge and sources of information among the Estonian population.

A survey on sex education and contraceptive methods was carried out within a monthly EMOR Omnibus Survey. By using a questionnaire, knowledge and attitudes, as well as the main sources of information on contraceptive methods and sex education, among the Estonian adult population (n = 618) was investigated. Of the respondents, 68% were female and 32% were males: the mean age was 34 years. Almost all respondents expressed the opinion that sex education should start at school and that education on contraceptive methods would reduce the number of abortions. The majority of the respondents believed that it would be more convenient to visit a family doctor than a gynecologist for family planning. Main sources of information on contraception were: literature, doctors and journals, as rated by females; and literature, partners and television, as rated by males. The roles of the school nurse, father and siblings were rated as comparatively small. The level of respondents' knowledge of contraceptive methods was not too high. It is concluded that the prerequisites for changing sexual behavior and knowledge over a short time are wider use of mass media and better sex education at schools. Also, it is necessary to prepare family doctors to offer family planning services to their patients.

Adult

[Health education--knowledge and sources of information about acquired immunodeficiency or AIDS].

Questionnaires were answered by 151 students, 10 to 19 years old, from an elementary, Jr. and Senior-high State School in Florianópolis, State of Santa Catarina-Brazil. The objectives were: to identify information sources; transmission mechanisms; prevention forms and the interest shown by students in acquiring new knowledge on HIV/AIDS. Based on the responses, authors found out that 90.06% of the students had heard about AIDS on TV, 29.13% had been informed about the theme through a teacher. It was also observed that 45.03% would seek for orientation from their parents, and 9.93% from their teachers.

Acquired Immunodeficiency Syndrome

Evaluating the coverage of controlled health data terminologies: report on the results of the NLM/AHCPR large scale vocabulary test.

OBJECTIVE: To determine the extent to which a combination of existing machine-readable health terminologies cover the concepts and terms needed for a comprehensive controlled vocabulary for health information systems by carrying out a distributed national experiment using the Internet and the UMLS Knowledge Sources, lexical programs, and server. METHODS: Using a specially designed Web-based interface to the UMLS Knowledge Source Server, participants searched the more than 30 vocabularies in the 1996 UMLS Metathesaurus and three planned additions to determine if concepts for which they desired controlled terminology were present or absent. For each term submitted, the interface presented a candidate exact match or a set of potential approximate matches from which the participant selected the most closely related concept. The interface captured a profile of the terms submitted by the participant and for each term searched, information about the concept (if any) selected by the participant. The term information was loaded into a database at NLM for review and analysis and was also available to be downloaded by the participant. A team of subject experts reviewed records to identify matches missed by participants and to correct any obvious errors in relationships. The editors of SNOMED International and the Read Codes were given a random sample of reviewed terms for which exact meaning matches were not found to identify exact matches that were missed or any valid combinations of concepts that were synonymous to input terms. The 1997 UMLS Metathesaurus was used in the semantic type and vocabulary source analysis because it included most of the three planned additions. RESULTS: Sixty-three participants submitted a total of 41,127 terms, which represented 32,679 normalized strings. More than 80% of the terms submitted were wanted for parts of the patient record related to the patient's condition. Following review, 58% of all submitted terms had exact meaning matches in the controlled vocabularies in the test, 41% had related concepts, and 1% were not found. Of the 28% of the terms which were narrower in meaning than a concept in the controlled vocabularies, 86% shared lexical items with the broader concept, but had additional modification. The percentage of exact meanings matches varied by specialty from 45% to 71%. Twenty-nine different vocabularies contained meanings for some of the 23,837 terms (a maximum of 12,707 discrete concepts) with exact meaning matches. Based on preliminary data and analysis, individual vocabularies contained < 1% to 63% of the terms and < 1% to 54% of the concepts. Only SNOMED International and the Read Codes had more than 60% of the terms and more than 50% of the concepts. CONCLUSIONS: The combination of existing controlled vocabularies included in the test represents the meanings of the majority of the terminology needed to record patient conditions, providing substantially more exact matches than any individual vocabulary in the set. From a technical and organizational perspective, the test was successful and should serve as a useful model, both for distributed input to the enhancement of controlled vocabularies and for other kinds of collaborative informatics research.

Evaluation Studies as Topic

Evaluating the impact of a promotional campaign for screening mammography: women's knowledge and sources of awareness.

The Breast X-Ray Programme of the Central Sydney Health Service was advertised by generalised strategies aimed at the total community, including poster and pamphlet distribution, and strategies aimed at general practitioners, supplemented by written invitations and recommendation from the general practitioner, invitations for friends, and invitations from the service using the electoral listing. In order to evaluate the reach or impact of the promotional campaign in the Drummoyne local government area, telephone interviews were conducted with women aged 45 to 70 randomly selected from the community. Women's knowledge about breast cancer, screening and the Breast X-Ray Programme, plus sociodemographic characteristics, were obtained before screening (n = 628), 10 months (n = 93) and 2 years after screening started (n = 206). While knowledge about risk did not change, significant increases were found in the proportion of women who had heard of mammography, screening mammography specifically and the screening van. In addition there were significant increases in the proportion of women exposed to information about screening mammograms. The campaign generally had an equal effect on different sociodemographic but managed to achieve greater effects in women of non-English-speaking backgrounds and lower occupational status. A random sample of program attenders aged 45 to 70 (n = 763) were asked how they found out about the van. 'Seeing the van' was the most consistently reported source of awareness. Others included 'GPs' 'newspapers', 'other print media' and 'personal networks'. Women with additional qualifications since leaving school were more likely to state 'newspaper' and 'other print media' as a source.

Aged

An overview of statistical methods for the classification and retrieval of patient events.

Statistical methods that can support text retrieval are becoming an increasing focus of medical informatics activities. We overview our adaptation of existing knowledge sources to create pseudo-documents for concept based latent semantic indexing. Experience demonstrated this tack of limited practical value, since retrieval performance was invariably unsatisfactory. We discovered this was due in part to the introduction of a vocabulary gap between the queries and the cases we sought to retrieve. In part to address this problem, and to avail our large body of humanly coded text as a knowledge source, we developed a least squares fit alternative for the computer assisted indexing and retrieval of biomedical texts. This technique demonstrates equivalent or superior retrieval performance when compared to all other textual retrieval techniques. It does not depend upon elaborate knowledge bases, lexicons, or thesauri. It is a promising technique for classifying and retrieving the large volumes of clinical text.

Abstracting and Indexing

The Unified Medical Language System: an informatics research collaboration.

In 1986, the National Library of Medicine (NLM) assembled a large multidisciplinary, multisite team to work on the Unified Medical Language System (UMLS), a collaborative research project aimed at reducing fundamental barriers to the application of computers to medicine. Beyond its tangible products, the UMLS Knowledge Sources, and its influence on the field of informatics, the UMLS project is an interesting case study in collaborative research and development. It illustrates the strengths and challenges of substantive collaboration among widely distributed research groups. Over the past decade, advances in computing and communications have minimized the technical difficulties associated with UMLS collaboration and also facilitated the development, dissemination, and use of the UMLS Knowledge Sources. The spread of the World Wide Web has increased the visibility of the information access problems caused by multiple vocabularies and many information sources which are the focus of UMLS work. The time is propitious for building on UMLS accomplishments and making more progress on the informatics research issues first highlighted by the UMLS project more than 10 years ago.

Computer Communication Networks

[A study on the factors affecting friendship with HIV-infected students in high school: from the survey of AIDS related knowledge, information sources and attitudes in 1989 and 1992].

To clarify the factors affecting the friendship with human immunodeficiency virus (HIV)-infected persons, a self-reported questionnaire study was conducted in two high schools in Tokyo in 1989 and 1992. A complete set of responses was obtained from 541 (98%) and 517 (99%) students in 1989 and 1992, respectively. The following results were obtained: 1) The proportion of the students who received information on HIV/acquired immunodeficiency syndrome (AIDS) from school teachers in 1992 was higher than that in 1989 for both males and females. Similarly, for both males and females, the proportion of students with correct knowledge on HIV transmission was significantly higher in 1992. The proportion of the students who intended to have a friendship with a hypothetical HIV-infected classmate or close friend in 1992 was significantly higher. 2) The results of multiple logistic regression analysis indicated that such factors as having more correct knowledge on HIV transmission and considering the confidentiality of persons with HIV/AIDS were significantly related to having friendship with a hypothetical HIV-infected classmate for both 1989 and 1992; such factors as being a female and having an increasing risk of HIV infection were significantly related to the responses obtained for 1992.

Acquired Immunodeficiency Syndrome

Data-source effects on the sensitivities and specificities of clinical features in the diagnosis of rheumatoid arthritis: the relevance of multiple sources of knowledge for a decision-support system.

An experimental computer system was developed to support diagnosis of rheumatic disorders by computing diagnostic probabilities using modified likelihood ratios. The authors examined whether the performance of the model was affected by the settings in which the data used to derive the likelihood ratios were collected. The sensitivities and specificities of various clinical features for diagnosing rheumatoid arthritis (RA) were obtained from: 1) a study of 1,570 consecutive outpatients at a rheumatology clinic; 2) a review of the literature; 3) estimates by rheumatologists; and 4) a population study. Considerable variations in sensitivity and specificity but satisfactory agreement in likelihood ratios were found across the four data sets. The likelihood ratios were then used to compute the probabilities of RA in a test series of 570 of the rheumatology clinic outpatients. The model's diagnoses with likelihood ratios from the other sources were adequate. When the likelihood ratios from these sources were combined, discrimination came close to what could be achieved by using the likelihood ratios based on the data from the clinic. The method applied in the study, which makes use of variation of input data instead of variation of test series, and the results are relevant to assessing the external validity and transferability of Bayesian decision-support systems.

Adolescent

A Web terminology server using UMLS for the description of medical procedures.

The Model for Assistance in the Orientation of a User within Coding Systems (MAOUSSC) project has been designed to provide a representation for medical and surgical procedures that allows several applications to be developed from several viewpoints. It is based on a conceptual model, a controlled set of terms, and Web server development. The design includes the UMLS knowledge sources associated with additional knowledge about medico-surgical procedures. The model was implemented using a relational database. The authors developed a complete interface for the Web presentation, with the intermediary layer being written in PERL. The server has been used for the representation of medico-surgical procedures that occur in the discharge summaries of the national survey of hospital activities that is performed by the French Health Statistics Agency in order to produce inpatient profiles. The authors describe the current status of the MAOUSSC server and discuss their interest in using such a server to assist in the coordination of terminology tasks and in the sharing of controlled terminologies.

Computer Communication Networks

[Prions and Trypanosoma as a source of knowledge of the brain].

Recent research on prions and trypanosomes is reviewed as they constitute examples of how infectious agents can cause degenerative diseases or functional disturbances in the nervous system. Prions are novel, transmissible pathogens causing degenerative diseases of the central nervous system both in humans and in animals. Kuru, Creutzfeldt-Jakob's disease and Gerstmann-Sträussler-Scheinker's (GSS) syndrome illustrate the acquired, sporadic and genetic manifestations of the human prion diseases, respectively. Prions are composed largely, if not entirely, of an abnormal isoform of the prion protein, which is a normal cellular protein occurring at high concentrations in the central nervous system. Specific mutations in the prion gene may cause the sporadic and hereditary human disease. S B Prusiner's group at the University of California has used genetic engineering techniques to recreate GSS syndrome by transplanting the mutated prion gene into mice in which the effects of the prion protein genes can then be studied. Trypanosomes are extracellular parasites which cause distinct functional disturbances of the nervous system, although they do not penetrate the blood-brain barrier. Factors are now being isolated in the interactions between the parasites and the immunesystem, and the effects of such factors on the functional properties of neurons are studied.

Animals