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PubMed2000

Sources of information used by patients to learn about chemotherapy side effects.

BACKGROUND: Little is known about the relative importance of specific information sources patients use to obtain knowledge about treatment side effects. The authors examined information sources used to learn about side effects, why patients believe they will experience some but not others, and the meanings side effects have in terms of treatment efficacy. METHODS: Before treatment, 31 ovarian cancer patients and 81 men and women with a variety of cancer diagnoses completed a questionnaire assessing their expectations about experiencing specific side effects of chemotherapy and information sources used. RESULTS: The doctor or nurse was the most frequently cited source of side-effect information, with readings second. While most thought they would get certain side effects because the doctor or nurse had said so, most instinctively believed they would not get others. CONCLUSIONS: Patients relied on medical and non-medical information sources. Further research could examine other sources for their influences on information-seeking activities.

Aged↗
PubMed1996

Planar imaging quantification using 3D attenuation correction data and Monte Carlo simulated buildup factors.

A new method to correct for attenuation and the buildup of scatter in planar imaging quantification is presented. The method is based on the combined use of 3D density information provided by computed tomography to correct for attenuation and the application of Monte Carlo simulated buildup factors to correct for buildup in the projection pixels. CT and nuclear medicine images were obtained for a purpose-built nonhomogeneous phantom that models the human anatomy in the thoracic and abdominal regions. The CT transverse slices of the phantom were converted to a set of consecutive density maps. An algorithm was developed that projects the 3D information contained in the set of density maps to create opposing pairs of accurate 2D correction maps that were subsequently applied to planar images acquired from a dual-head gamma camera. A comparison of results obtained by the new method and the geometric mean approach based on published techniques is presented for some of the source arrangements used. Excellent results were obtained for various source-phantom configurations used to evaluate the method. Activity quantification of a line source at most locations in the nonhomogeneous phantom produced errors of less than 2%. Additionally, knowledge of the actual source depth is not required for accurate activity quantification. Quantification of volume sources placed in foam, Perspex and aluminium produced errors of less than 7% for the abdominal and thoracic configurations of the phantom.

Biophysical Phenomena↗
PubMed2002

The relative importance of water and food as cadmium sources to Daphnia magna Straus.

Knowledge of the transport pathways of metals into aquatic organisms is paramount in determining the metal's potential mechanism of toxicity. To determine the relative importance of water and food as cadmium (Cd) sources for the cladoceran Daphnia magna grazing on the algae Chlorella vulgaris, we measured cadmium accumulation and toxicity (feeding inhibition and survival) in three genetically different clones of D. magna subsequent to water, food, and water and food exposures. We found that Cd uptake from water and food was independent of source and additive in effect, with D. magna juveniles accumulating twice as much Cd from water than from food (algae). However, the efficiency with which Cd was assimilated by D. magna from its algal diet was much higher (10%) than from water (0.3%). Uptake and toxic responses were inversely related: tolerant clones accumulated more Cd. As a consequence, models based on uptake of metals from the combined routes of water and food may be reliable to predict metal dynamics in the field, but may fail to predict toxic effects since tolerance to metals is not necessarily linked to reduced total uptake of metals.

Absorption↗
PubMed1990

[Hospital employees' knowledge about HIV disease. A study from 2 provincial hospitals].

The knowledge of and attitudes to HIV infection were investigated by means of questionnaires during the period 1.10.1988 to 30.4.1989 in two small Danish Hospitals. Two hundred and thirty two nurses, 147 nursing aids, 44 doctors, 25 laboratory workers and 22 midwives took part in the investigation. The overall response was 99% of the staff contacted. The questionnaires were anonymous and were completed immediately and without use of any sources of information. Poor knowledge was revealed concerning symptoms, sources of infection, precautions to avoid infection, high-risk groups and patients duty to provide information. In fact, none of the groups exceeded 66% correct answers on these subjects. A total of 70% of the whole group had been in contact with patients, whom they suspected to be HIV-positive. Every third individual had felt insecure regarding HIV at work. Incidents at work had caused 18 employees to be tested for HIV. Only about half had been instructed about HIV. A total of 73% expressed needs for further instruction about the disease. The investigation shows difference between the staff opinion of possible claims on the patients about tests and to the policy of the Danish Department of Health concerning voluntary testing.

Denmark↗
PubMed2000

The grid that bridges the gap.

Since the introduction of the Diploma in Higher Education in Nursing Studies (Dip HE NS) at this Faculty, course evaluations have consistently reported students' fears and apprehensions which result from their perceived lack of practical ability. Their experiences are supported by accounts from other nursing faculty (Elkan et al. 1993, Jowett & Walton 1994). In 1994, following analysis of course evaluations and a review of the literature on skill acquisition, experiential skills teaching was resumed within the faculty setting. This was after a period in the late 1980s when the cultural thinking was that 'practice suites' were to be frowned upon, and that skills were best taught in practice placements. Despite rigorous literature reviews (Love et al. 1989, Knight 1996) there appears to be no research to support the dismantling of practice suites. A structured approach to teaching skills now takes place in a purpose built Skills Centre. The approach used is based on a model by Gentile (1972), which is founded upon the theoretical principles of skill acquisition. It provides a blueprint for the teaching and transference of skills, and implicit in the model is the use of skill analysis. This involves demonstration of a skill by the facilitator, followed by analysis of it by the student into its component parts; this is followed by practise. The authors were concerned, however, that the use of skill analysis to teach skills should not be reduced to a presentation of a succession of isolated tasks. The authors were also aware that a nursing skill often has a tendency to be viewed purely within the psychomotor domain, with little attention paid to the knowledge base which underpins the skill. This viewpoint may contribute to the notion of a theory-practice gap. In response to these concerns, the authors have developed the Skill Grid. The grid incorporates skill analysis with Carper's theoretical framework: Fundamental Ways of Knowing (Carper 1975). The authors believe that knowledge which exemplifies nursing practice has many dimensions, and that it is crucial for students to explore the derivation of knowledge from an ontological perspective. Carper's framework will enable consideration of knowledge originating not only from empirical, but also aesthetic, personal and ethical sources. An essential feature of the grid is the attempt to link knowledge with practice by demonstrating how Carper's framework, which identifies sources of knowledge, can form the basis for the acquisition of skill. The authors have also incorporated problem-based learning into their teaching, so that the skills are practised within a patient/client orientated situation.

Attitude of Health Personnel↗
PubMed2001

Knowledge integration: insight through the E-portal.

Data become information when they can be summarized and organized into logical patterns; information becomes knowledge when it can be manipulated for actionable decision making; knowledge becomes insight when contextually relevant and temporarily appropriate. This article describes how information technology can now be used to provide clinicians with access to both insight and information that is context- and event-sensitive. Collaboration between the American College of Physicians, medical knowledge experts, Oregon Health Sciences University (OHSU), and shared medical systems for framework and infrastructure combine to create the ideal environment of complementary and synergistic competencies. This article describes the research that is under way at OHSU to determine how to deploy medical knowledge derived from these sources and integrate it into the clinical workflow; it also examines a vision of how medical knowledge can be integrated in the future.

Education, Medical, Continuing↗
PubMed1997

Maternal and foetal ECG separation using blind source separation methods.

The separation of the maternal and foetal electrocardiograms (ECGs) from skin electrodes located on the mother's body may be modelled as a blind source separation (BSS) problem. This consists in the reconstruction of a set of unknown mutually independent source signals from the sole knowledge of another set of linear mixtures of the sources, where the mixture pattern is also unknown. Three BSS methods based on cumulants are considered: principal-component analysis (PCA), higher-order singular-value decomposition (HOSVD), and higher-order eigenvalue decomposition (HOEVD). All these methods are applied to the foetal-ECG extraction problem by using real ECG data. The last two methods appear to provide a more satisfactory separation than the first method, with HOEVD offering slightly better results.

Biomedical Engineering↗
PubMed1999

Source point calibration from an arbitrary electron backscattering pattern.

Precise knowledge of the position of the source point is a requirement if electron backscattering patterns (EBSPs) are to be used for crystal orientation measurements or other types of measurements which demand a geometrical analysis of the patterns. Today, possibly the most popular method for locating the source point is a computational technique which uses the positions of a number of indexed Kikuchi bands for calculating the coordinates of the point. A serious limitation of this calibration technique is, however, that the localized bands must first be indexed, which is difficult if the location of the source point is not known with reasonable precision. This paper describes a new technique which determines the location of the source point from the positions of a number of bands in an arbitrary EBSP. Besides the positions of the Kikuchi bands, the only information which is required by this new calibration procedure is the same crystallographic information which is used for normal indexing of EBSPs. The procedure is shown to work successfully with patterns from a simple cubic crystal, as well as with patterns from an orthorhombic BiSCCO superconductor. In the former case, four bands are shown to be sufficient to ensure a unique determination of the source point, whereas five bands are required in the latter case. Once the bands have been localized, the time required for calculating the source point position is of the order of 1 min on a standard PC.

Journal Article↗
PubMed2001

The use of an MEG device as 3D digitizer and motion monitoring system.

An algorithm is described that localizes a set of simultaneously activated coils using MEG detectors. These coil positions are used for continuous or intermittent head position registration during long MEG sessions, to coregistrate MR and MEG data and to localize EEG electrodes attached to the scalp, when EEG and MEG are recorded simultaneously. The algorithm is based on a mathematical model in which the coils are described as stationary magnetic dipoles with known source time functions. This knowledge makes it possible to detect and remove bad channels automatically. It is also assumed that the source time functions are orthogonal. Therefore, the localization problem splits into independent localization problems. for each coil. The method is validated in a phantom experiment, where the relative coil positions were known. From this experiment it is found that the average error is 0.25 cm. An error of 0.23 cm was found in an experiment where 64 electrode positions were measured four times independently. Examples of the applications of the method are presented. Our method eliminates the use of an external 3D digitizer and maps the MEG directly onto other modalities. This is not only a practical advantage, but it also reduces the gross registration error. Furthermore, head motions can be monitored and MEG data can be corrected for these motions.

Algorithms↗
PubMed2004

delta-Aminolevulinic acid and blue light photodynamic therapy for treatment of multiple basal cell carcinomas in two patients with nevoid basal cell carcinoma syndrome.

BACKGROUND: Patients with nevoid basal cell carcinoma syndrome suffer from multiple basal cell carcinomas, requiring numerous surgical procedures that over time leave them with multiple disfiguring scars. Photodynamic therapy with delta-aminolevulinic acid using red light (approximately 630 nm) sources has been reported as effective in treatment of superficial and small nodular basal cell carcinomas. To our knowledge, the blue light source (417 nm peak irradiance) approved by the FDA for treatment of actinic keratoses has not been used for photodynamic therapy with delta-aminolevulinic acid of basal cell carcinoma. OBJECTIVE: We report treatment of two nevoid basal cell carcinoma syndrome patients, women aged 21 and 47, with 20%delta-aminolevulinic acid solution and 417-nm blue light source (irradiance 10 mW/cm(2)). METHODS: delta-Aminolevulinic acid was applied topically on lesions 1 to 5 hr before light treatment. Lesions were illuminated with 417+/-5-nm blue light for 1000 sec (10 J/cm(2)). Two consecutive treatments 1 week apart were administered as a therapeutic course. Each patient underwent two courses of photodynamic therapy with delta-aminolevulinic acid 2 to 4 months apart. The reported assessment was made 8 months after initial treatment. In most sessions the entire face, rather than visible basal cell carcinomas only, was treated. The treated basal cell carcinomas were clinically subdivided to superficial or nodular type guided by their morphologic features. A total of 9 superficial and 16 nodular basal cell carcinomas on the face and 27 superficial basal cell carcinomas on the lower extremities were treated. RESULTS: Complete clinical response was observed in 8 of 9 (89%) superficial basal cell carcinomas and 5 of 16 (31%) nodular basal cell carcinomas on the face and in 18 of 27 (67%) of superficial basal cell carcinomas on the lower extremities. The remaining 21 lesions showed partial clinical resolution. No new basal cell carcinomas were observed during the 8-month follow-up period in areas treated with a broad application technique. Resolution of the lesions was accompanied by an excellent cosmetic outcome and decreased prominence of old surgical scars in the more severely affected patient. Treatments were well tolerated, but associated with moderate to severe stinging during illumination. CONCLUSION: To our knowledge this is the first use of photodynamic therapy with delta-aminolevulinic acid with 417-nm blue light for treatment of multiple basal cell carcinomas in patients with nevoid basal cell carcinoma syndrome. Our clinical results demonstrate that the blue light reduces cutaneous tumor burden in such patients. Further studies are needed to confirm that broad-area photodynamic therapy with delta-aminolevulinic acid may eradicate subclinical tumors in nevoid basal cell carcinoma syndrome sufferers, as suggested by a strikingly decreased incidence of new basal cell carcinomas in our patients.

Adult↗
PubMed2000

People's knowledge and practice about dengue, its vectors, and control means in Brasilia (DF), Brazil: its relevance with entomological factors.

In South America, the epidemiology and ecology of dengue fever are strongly associated with human habits because the vector Aedes aegypti is strictly urban. Thus, the evaluation of people's knowledge and practice (PKP) is of great importance to improve integrated control measures. A PKP evaluation has been done in a suburb of Brasilia. Thirty questions were submitted to 130 habitants about income level, education, sources of information, specific knowledge about dengue, vector biology, and control measures applied. Other questions were about the responsibility of dengue control and the opportunity of applying a fine to people who would not cooperate with the control measures. Level of PKP was fairly high, either for housekeepers, workers, or students. The mosquito bite was cited as source of infection by 60.8% of interviewed people but 22.3% had no knowledge about this topic. The most cited symptoms in association with dengue were fever (73.1%), headache (66.2%), and rash (35.4%). Knowledge about mosquito biology and control was also fairly accurate, as demonstrated by 96.9% of answers. Elimination of water containers was the most efficient means according to 73% of people. Such action should be done mainly by the citizen (75.3% of answers). Despite the good PKP, correlations existed only between the PKP about vector biology and presence of potential breeding containers in March, and between the PKP about the disease and potential breeding containers in April. In conclusion, global educational campaigns may have a real impact on the PKP but this did not result in effective control of the mosquito breeding containers by the people.

Aedes↗
PubMed2004

Techniques for optimization of queries on integrated biological resources.

Today, scientific data are inevitably digitized, stored in a wide variety of formats, and are accessible over the Internet. Scientific discovery increasingly involves accessing multiple heterogeneous data sources, integrating the results of complex queries, and applying further analysis and visualization applications in order to collect datasets of interest. Building a scientific integration platform to support these critical tasks requires accessing and manipulating data extracted from flat files or databases, documents retrieved from the Web, as well as data that are locally materialized in warehouses or generated by software. The lack of efficiency of existing approaches can significantly affect the process with lengthy delays while accessing critical resources or with the failure of the system to report any results. Some queries take so much time to be answered that their results are returned via email, making their integration with other results a tedious task. This paper presents several issues that need to be addressed to provide seamless and efficient integration of biomolecular data. Identified challenges include: capturing and representing various domain specific computational capabilities supported by a source including sequence or text search engines and traditional query processing; developing a methodology to acquire and represent semantic knowledge and metadata about source contents, overlap in source contents, and access costs; developing cost and semantics based decision support tools to select sources and capabilities, and to generate efficient query evaluation plans.

Algorithms↗
PubMed2004

Mapping various information sources to a semantic network.

Giessen Data Dictionary Server (GDDS) provides context sensitive information services to disparate clinical applications by automatically navigating a semantic network that stores medical knowledge. Mapping multiple information sources to single clinical application becomes a challenge due to different organization of semi-structured information sources. Linking huge unstructured information sources such as medical literature is even more challenging because we need to develop a mechanism to organize unstructured information and take into account the scalability issue. In this paper, we have successfully mapped two drug information sources by developing an independent subnet for each source and linking them at proper nodes. For medical literature, we have demonstrated that the semantic network of the Unified Medical Language Systems and human assigned topics to each document can be used to organize the large amount of medical literature into the framework of the GDDS service.

Dictionaries, Medical as Topic↗
PubMed2002

The impact of bowel cancer awareness week.

OBJECTIVES: To assess knowledge of Bowel Cancer Awareness Week (BCAW) amongst patients attending their general practice surgery and to identify whether BCAW could increase knowledge of colorectal cancer symptoms. METHOD: Questionnaire study with ethics committee approval. Patients attending non-emergency clinics in a single general practice during the week following BCAW were given a questionnaire. Respondents were asked for knowledge of colorectal cancer symptoms, sources of this information and awareness of BCAW compared to similar knowledge of breast cancer. RESULTS: Seventy-seven patients responded (96% response rate, median age 42, 40% male). Eighty-five percent could name a breast cancer symptom compared to only 44% who could name a colorectal cancer symptom (McNemar's chi2, P < 0.0001). Respondents identified more sources of information for breast than colorectal cancer. Only 21% had heard of BCAW and none could name any symbol for bowel cancer awareness whereas 69% were aware of Breast Cancer Awareness Month and 28% could name its symbol (McNemar's chi2, P < 0.0001). Multivariate analysis demonstrated that patients who were aware of BCAW were 4.6 times more likely to have knowledge of colorectal cancer symptoms (95% CI 1.25-17.1). CONCLUSIONS: Despite their similar incidence, knowledge of colorectal cancer is much less than breast cancer. In part this may be due to the greater publicity given to breast cancer. BCAW can increase knowledge of colorectal cancer symptoms but currently, too few people are aware of it.

Journal Article↗
PubMed2001

Obstetrician-gynecologists' knowledge and training about antenatal corticosteroids.

OBJECTIVE: To characterize the clinical decisions, knowledge, opinions, and education of obstetricians and gynecologists about antenatal corticosteroids. METHODS: Questionnaires mailed to 1020 ACOG Fellows included items on demographics, knowledge, clinical practice patterns, and educational background regarding antenatal corticosteroids. RESULTS: The survey response rate was 47.8%. Almost all respondents (94%) reported administering antenatal corticosteroids, with reduction of respiratory distress syndrome (82%) as the primary reason for antenatal corticosteroid administration. Most (59.2%) were unaware of newly recognized associations between multiple administrations of corticosteroids and fetal growth restriction. In hypothetical clinical situations, responses by physicians who completed their residency training before 1970 indicated less likelihood to administer corticosteroids when administration is relatively indicated per National Institutes of Health (NIH) and ACOG guidelines than those trained later (P <.001). Only 8% of the entire sample rated their knowledge of antenatal corticosteroids as comprehensive; most (68%) rated it as adequate. Respondents rated residency training as a much better source of antenatal corticosteroid knowledge than medical school. CONCLUSION: Most obstetrician-gynecologists reported using antenatal corticosteroids; however, in general, many were not aware of more recent information regarding potential risks. This survey suggests that a multipronged educational approach is warranted to update obstetrician-gynecologists about antenatal corticosteroids.

Adult↗
PubMed1989

An AI-based communication system for motor and speech disabled persons: design methodology and prototype testing.

An intelligent communication device is developed to assist the nonverbal, motor disabled in the generation of written and spoken messages. The device is centered on a knowledge base of the grammatical rules and message elements. A "belief" reasoning scheme based on both the information from external sources and the embedded knowledge is used to optimize the process of message search. The search for the message elements is conceptualized as a path search in the language graph, and a special frame architecture is used to construct and to partition the graph. Bayesian "belief" reasoning from the Dempster-Shafer theory of evidence is augmented to cope with time-varying evidence. An "information fusion" strategy is also introduced to integrate various forms of external information. Experimental testing of the prototype system is discussed.

Artificial Intelligence↗
PubMedDate not supplied

Beyond knowledge deficit to a proposal for information-seeking behaviors.

TOPIC: Nursing assessment of knowledge of informational needs. PURPOSE: To present of a brief evolutionary analysis of knowledge deficit in terms of its significance, application, and use, and to present a proposal diagnosis, "information-seeking behaviors." SOURCES: Literature review of knowledge deficit and "information-seeking behaviors." CONCLUSIONS: Knowledge deficit is a nursing diagnosis that is significant for identifying a patient's need for education or knowledge. Its application has revealed limitations to validity and subsequent use. "Information-seeking behaviors" is proposed as an alternative diagnosis. Antecedents and defining characteristics are presented and areas for future research proposed.

Humans↗
PubMed2001

Studying the effects of health plan competition: are available data resources up to the task?

OBJECTIVES: To review the availability of data sources to study health plan competition in the United States. DATA SOURCES: The literature on health plan competition was reviewed. Possible data sources to study health plan competition were evaluated. Experts in the field of health plan competition were contacted about their knowledge of existing data sources. Principal Findings. There is much more quantitative data available on HMO plans than on other types of health plans that are growing in popularity, such as PPOs. A key source for health plan data, state health insurance filings, lacks information on beneficiaries in non-HMO plans. Data on health plan quality is growing. In addition, case studies of particular markets is providing useful qualitative information on the dynamics of the health plan industry. CONCLUSIONS: The fragmentation of the health care market and the hesitancy of governments and private organizations to provide detailed information across markets and providers creates serious obstacles to the study of health plan competition.

Databases, Factual↗