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The European Childhood Obesity Group (ECOG) project: the European collaborative study on the prevalence of obesity in children.

During the European Congress on Obesity held in Barcelona in 1996, the European Childhood Obesity Group (ECOG) proposed a study designed to estimate the prevalence of obesity by country. An overview of existing systems revealed that most countries have no suitable structure in place for the determination of obesity in children and that the most practical sources of samples would be the school systems. A protocol was drawn up for these countries, whereas for those countries already collecting data, guidelines were defined to clarify the criteria allowing inclusion in the common analysis. The target population is 7-9-y-old children. The study design consists of separate cross-sectional population studies by country with a cluster probability sample of 2000 children attending primary school. The minimum common data will be age, weight, height, and hip, thigh, and waist circumferences. The participating countries will be encouraged to collect harmonized data on social indicators, lifestyle, diet, physical activity, and anthropometric measures of the parents. Children will be measured either by centrally based traveling examiners or, in countries with limited resources, by local staff. Each country will computerize its own data and send a copy to a center responsible for the common analysis. The main analysis will be of body mass index distribution in children from the different populations and determination of the proportion of children with a BMI above the 90th percentile of a common reference population. Members of the ECOG in 14 European countries have confirmed their interest in the project.

Journal Article↗

Microarray data mining with visual programming.

UNLABELLED: Visual programming offers an intuitive means of combining known analysis and visualization methods into powerful applications. The system presented here enables users who are not programmers to manage microarray and genomic data flow and to customize their analyses by combining common data analysis tools to fit their needs. AVAILABILITY: http://www.ailab.si/supp/bi-visprog SUPPLEMENTARY INFORMATION: http://www.ailab.si/supp/bi-visprog.

Chromosome Mapping↗

Assessing the quality of project data by means of a data sufficiency categorization scheme.

Improving the quality of gathered or abstracted data is often an important part of a quality improvement project's early stages. This is especially so if indicators will be compared across providers or if various data elements will be used for severity adjustment. One common data problem is missing data. This paper describes a flowchart-based approach for assessing the magnitude of missing data problems. The approach is demonstrated by means of two indicators currently used in multihospital cooperative improvement projects. The approach results in assigning each observation (e.g., patient record) in a sample into one of five data categories. These categories follow standard definitions advanced by the Joint Commission on Accreditation of Healthcare Organizations. Two of the categories tally observations with missing data problems. Assessment of missing data can be viewed as one component of reliability assessment, and its relationship to other forms of reliability assessment is discussed, with emphasis on the relationship to interrater agreement.

Abstracting and Indexing↗

The CAP cancer protocols--a case study of caCORE based data standards implementation to integrate with the Cancer Biomedical Informatics Grid.

BACKGROUND: The Cancer Biomedical Informatics Grid (caBIG) is a network of individuals and institutions, creating a world wide web of cancer research. An important aspect of this informatics effort is the development of consistent practices for data standards development, using a multi-tier approach that facilitates semantic interoperability of systems. The semantic tiers include (1) information models, (2) common data elements, and (3) controlled terminologies and ontologies. The College of American Pathologists (CAP) cancer protocols and checklists are an important reporting standard in pathology, for which no complete electronic data standard is currently available. METHODS: In this manuscript, we provide a case study of Cancer Common Ontologic Representation Environment (caCORE) data standard implementation of the CAP cancer protocols and checklists model--an existing and complex paper based standard. We illustrate the basic principles, goals and methodology for developing caBIG models. RESULTS: Using this example, we describe the process required to develop the model, the technologies and data standards on which the process and models are based, and the results of the modeling effort. We address difficulties we encountered and modifications to caCORE that will address these problems. In addition, we describe four ongoing development projects that will use the emerging CAP data standards to achieve integration of tissue banking and laboratory information systems. CONCLUSION: The CAP cancer checklists can be used as the basis for an electronic data standard in pathology using the caBIG semantic modeling methodology.

Clinical Protocols↗

Development of a multicenter interventional cardiology database: the Blue Cross Blue Shield of Michigan Cardiovascular Consortium (BMC2) experience.

The technical challenges in the development of a quality-controlled registry of percutaneous coronary interventions (PCIs) are currently unknown. This article describes the authors' experience in the development of a regional, quality-controlled PCI registry. In 1996, 16 centers in Michigan were invited to participate in a multicenter PCI registry. Nine centers agreed to a pilot data collection and, as of July 2001, eight centers are still actively collecting data. An Oracle database was developed by the coordinating center. A common data collection form and a standard set of definitions were agreed on during several meetings. Data validity was insured through review of each form by a trained nurse, by automatic database diagnostic routines, and by site visits that included a review of the catheterization laboratory logs and a review of randomly selected charts. The average number of forms requiring query resolution was 33% in 1997 (range 7-76%), and it decreased to 5% in 1999 (range 1.4-10%). The most commonly queried variables were outcomes prior to discharge, lesion category, lesion complexity, date of birth, device used, gender, postprocedural percent stenosis, presence of left main disease, and MI date. Invalid dates, identification of the doctor, the presence of duplicate forms, and of duplicate outcomes were additional common queries generated by the internal diagnostic routines. In conclusion, the number of queries and diagnostic reports generated in the database suggests that the development of a quality-controlled PCI registry requires the institution of a careful diagnostic and data quality assessment system.

Angioplasty, Balloon, Coronary↗

Common reference coherence data are confounded by power and phase effects.

Coherence analysis of the EEG is used to study the coupling between cortical regions. High coherence between signals recorded at 2 electrodes is interpreted as evidence for neuroanatomic connections between the cortical areas underlying the electrodes. When common reference recordings are used, coherence measures the relationship between 2 time series, each of which is the difference between 2 signals measured at the scalp and is confounded by spectral power and phase at the recording and reference electrodes. Using multi-channel EEG data from 3 subjects, we illustrate the confounding of common reference data coherence computations and demonstrate the extreme effects of power and phase changes on coherence by simulating these changes in the EEG data. Common reference coherence data can be either inflated or deflated as a consequence of activity (i.e., spectral power) at the reference. Phase relationships among the reference and recording time series modulate the power effects on coherence. Both the power and phase effects can vary dramatically across frequencies, having profound and complicated effects on the shape of the coherence function. Based on these considerations, we conclude that common reference coherence data must be interpreted very cautiously and recommend that a new body of EEG coherence data must be gathered using reference-free recording methods before the utility of EEG coherence analysis for understanding brain function can be determined.

Cerebral Cortex↗

Inform: conceptual modelling of intensive care information systems.

Intensive care of a patient requires heavy monitoring and versatile therapeutic actions. These produce a huge amount of patient information. A problem exists in managing this data and other information from all supporting activities creating a need for an automated information management system. To have a sound basis for future automated information systems in intensive care unit (ICU), a conceptual model is created to cover both the clinical and other activities of the ICU. The conceptual model consists of data flow diagrams and entity-relationship diagrams with underlying common data dictionary. A modern CASE tool is utilized to build the model. The work forms a part of AIM-INFORM project, which has a purpose to develop information management and decision support systems for high dependency environment.

Computer Simulation↗

Demography and computer simulation in historic village population reconstruction.

"Demographic anthropology has given rise to methodological advances in the analysis of single community populations. However, the obstacles of small data bases and incomplete vital-event registration remain. This paper details one approach to these problems; the principles of community demography are incorporated with computer simulation methodology, with the goals of validating the internal consistency of and determining demographic secular trends from data commonly utilized in anthropological investigations." The approach is tested on data for the 250 inhabitants of Old Crow Village, Yukon Territory, Canada, in 1978.

Americas↗

Use of Bayesian Markov Chain Monte Carlo methods to model cost-of-illness data.

It is well known that the modeling of cost data is often problematic due to the distribution of such data. Commonly observed problems include 1) a strongly right-skewed data distribution and 2) a significant percentage of zero-cost observations. This article demonstrates how a hurdle model can be implemented from a Bayesian perspective by means of Markov Chain Monte Carlo simulation methods using the freely available software WinBUGS. Assessment of model fit is addressed through the implementation of two cross-validation methods. The relative merits of this Bayesian approach compared to the classical equivalent are discussed in detail. To illustrate the methods described, patient-specific non-health-care resource-use data from a prospective longitudinal study and the Norfolk Arthritis Register (NOAR) are utilized for 218 individuals with early inflammatory polyarthritis (IP). The NOAR database also includes information on various patient-level covariates.

Arthritis↗

Modulation of acetylcholine release by presynaptic muscarinic autoreceptors.

The existence of a modulatory system controlling the acetylcholine (ACh) release was first proposed for the nicotinic subtype in 1962. Following the first observation of a possible positive feedback loop activated by the released Ach, many studies were oriented in the investigation of the involved presynaptic autoreceptors. Most of the data have been obtained at the motor end-plate, commonly defined as the simplest model of peripheral synapse. The characterization of the chemical transmission since its first proposal showed a more complex pattern involving both the cholinergic and the adrenergic systems. It is now evident that this regulation is widespread both in the central and in the peripheral nervous system. The evidence that the release of ACh can be up- or down-regulated by the transmitter itself (autoregulation) or other neuromediators (heteroregulation) is now proved. In the last decades the attention was focused to the identification of the receptor subtypes located on the releasing nerve terminal. For the purpose, different techniques were used in the various laboratories. The functional approach was based mainly on the electrophysiological characterization of the events evolved prior, during and after the activation of the motor endplate nicotinic receptor. On the other hand, the overflow studies were carried out using radiolabeled ACh (rACh) obtained treating muscle fibers with radioactive choline (rCh). Many scientific papers proposed common data indicating a clear positive (nicotinic) or negative (muscarinic) modulation of the ACh release. Temporally, the description of the muscarinic regulation followed the discovery of the nicotinic one. However, by a pure pharmacological point of view it represents a challenge due to the more complex organization and function. In the peripheral nervous system, i.e. neuromuscular, the meaning of both the muscarinic and nicotinic modulations may appear as free of function. Conversely, in the central systems some effects, such as antinociception and others, could represent the basis of a functional activity such as proposed by Corrado group. The complete characterization of this phenomenon by a physiological and a pharmacological point of view could represents the goal for future uses and therapeutic potential. The present review illustrates the know how and the efforts in the characterisation of the muscarinic regulation of transmitter release from the beginning of its discovery trying to order the numerous scientific data published in this field. Furthermore, our personal data obtained with the Loose Patch Clamp (LPC) technique will be briefly presented and discussed. Our work was built up using agonists and antagonists of the muscarinic receptor subtype in the aim of better characterize the modulation function of the mediator Ach. We used carbachol (Cch), oxotremorine (Oxo) and dl-muscarine as agonists and 1-hyoscyamine, pirenzepine, ipratropium, 11[[2-1[(diethylamino) methyl-1-piperidinyl]-acetyl]-5, 11-dihydro-6H-pyrido [2,3-b][1,4] benzodiazepine-6-one (AFDX-116), methoctramine and 1,1-dimethyl-4 diphenylacetoxy-N-methylpiperidine (4-DAMP) as antagonists.

Acetylcholine↗

A simple data compression scheme for binary images of bacteria compared with commonly used image data compression schemes.

A run length code compression scheme of extreme simplicity, used for image storage in an automated bacterial morphometry system, is compared with more common compression schemes, such as are used in the tag image file format. These schemes are Lempel-Ziv and Welch (LZW), Macintosh Packbits, and CCITT Group 3 Facsimile 1-dimensional modified Huffman run length code. In a set of 25 images consisting of full microscopic fields of view of bacterial slides, the method gave a 10.3-fold compression: 1.074 times better than LZW. In a second set of images of single areas of interest within each field of view, compression ratios of over 600 were obtained, 12.8 times that of LZW. The drawback of the system is its bad worst case performance. The method could be used in any application requiring storage of binary images of relatively small objects with fairly large spaces in between.

Bacteria↗

Standardization of therapy machine interface for treatment monitoring.

Computerized monitoring of radiation treatments is an effective tool in detecting and preventing errors in treatment delivery. Most manufacturers now supply optional treatment monitoring (Record and Verify) systems. These differ significantly in their features and are, in general, incompatible with each other. Based on our examination of four different commercial systems, we believe that these commercial and individualized systems are not adequate and are difficult to use. In a radiation therapy facility with more than one treatment machine, it is highly desirable, for a variety of reasons, that such a system be implemented on a central computer which monitors all machines. A centralized record and verify system which allows the storage of all data on a long term basis in an on-line common data base permits much easier access to individual patient data as well as useful data analysis and reports. Every patient's demographic, prescription and treatment data are then available on all treatment machines. This is particularly useful for cases in which a patient may be transferred from one machine to the other. Such a system is also easier to operate. The development of such a treatment monitoring system requires that the protocol of communication between the therapy machine and the computer, and the data describing therapy machine settings transmitted to the computer be standardized. We propose that every manufacturer supply an optional interface meeting this standard. A description of the proposed standard evolved in four years of our work in this field is given.

Computers↗

Predicting impaired glucose tolerance using common clinical information: data from the Third National Health and Nutrition Examination Survey.

OBJECTIVE: To develop a score to predict impaired glucose tolerance (IGT) using common clinical data. RESEARCH DESIGN AND METHODS: We analyzed data from the Third National Health and Nutrition Examination Survey (NHANES III) for 2,746 individuals aged 40-74 years who completed an oral glucose tolerance test. IGT was defined as a 2-h postchallenge glucose > or =140 mg/dl (7.7 mmol/l). We performed bivariate and multivariate analyses to describe the association of IGT with commonly available clinical information. A numerical score to predict IGT was derived from the results of the multivariate logistic regression models. RESULTS: Fasting glucose levels between 101 and 109 mg/dl (5.6 and 6.0 mmol/l) or between 110 and 125 mg/dl (6.1 and 6.9 mmol/l) were associated with IGT (odds ratio 1.8 and 6.2, respectively; P < 0.05). BMI > or =25 kg/m(2), Mexican-American ethnicity, age between 60 and 74 years, hypertension, and triglyceride level > or =150 mg/dl (1.69 mmol/l) were also associated with IGT. The area under the receiver operating characteristic curve for an 8-point scale derived from the multivariate analysis was 0.74 (95% CI 0.72-0.76). Setting a low cut point of 2 on this scale resulted in high sensitivity (86%), whereas a high cut point of 6 yielded high specificity (97%) for the detection of IGT. CONCLUSIONS: A numerical score based on common clinical data can identify individuals with a low or high likelihood of having IGT.

Adult↗

Object-oriented data handler for sequence analysis software development.

We report an object-oriented data handler and supplementary tools for the development of molecular genetics application software for various sequence analyses. Our data handler has a flexible and expandable format that supports the most common data types for molecular genetic software. New data types can be constructed in an object-oriented manner from the basic units. The data handler includes an object library, a format-converting program and a viewer that can visualize simultaneously the data contained in several files to construct a general picture from separate data. This software has been implemented on an IBM PC-compatible personal computer.

Atrial Natriuretic Factor↗

TropGENE-DB, a multi-tropical crop information system.

TropGENE-DB, is a crop information system created to store genetic, molecular and phenotypic data of the numerous yet poorly documented tropical crop species. The most common data stored in TropGENE-DB are information on genetic resources (agro-morphological data, parentages, allelic diversity), molecular markers, genetic maps, results of quantitative trait loci analyses, data from physical mapping, sequences, genes, as well as the corresponding references. TropGENE-DB is organized on a crop basis with currently three running modules (sugarcane, cocoa and banana), with plans to create additional modules for rice, cotton, oil palm, coconut, rubber tree, pineapple, taro, yam and sorghum. The TropGENE-DB information system is accessible for consultation via the internet at http://tropgenedb.cirad.fr. Specific web consultation interfaces have been designed to allow quick consultations as well as complex queries.

Computational Biology↗

[Other infections (Streptococcus pneumoniae, Haemophilus influenzae, Pseudomonas aeruginosa, Salmonella spp., Campylobacter spp., Nocardia asteroides, Rhodococcus equi and Bartonella spp.)].

People infected with human immunodeficiency virus (HIV) are at increased risk for bacterial infections due to HIV-associated immunologic defects. Bacterial infections were found to be, both a predictor of progression to AIDS and a substantial cause of mortality in pre-AIDS stages. Most bacterial infections are caused by Streptococcus pneumoniae, Haemophilus influenzae, Salmonella spp. and Pseudomonas aeruginosa. Rhodococcus equi, Nocardia spp., Campylobacter spp. and Bartonella spp. are less common. Data derived from two AIDS Clinical Trials Group studies showed that the most common bacterial infections were sinusitis (8.5 per 100 episodes per person years [py]), bacterial pneumonia (5.0 per 100 py), bronchitis (4.1 per 100 py) and soft tissue infections (3.5 per 100 py). In this review clinical characteristics and treatment recommendations according to data available in the literature for these infections are summarized.

AIDS-Related Opportunistic Infections↗

GAW12: simulated genome scan, sequence, and family data for a common disease.

The Genetic Analysis Workshop (GAW) 12 simulated data involves a common disease defined by imposing a threshold on a quantitative liability distribution. Associated with the disease are five quantitative risk factors, a quantitative environmental exposure, and a dichotomous environmental variable. Age at disease onset and household membership were also simulated. Genotype data, including 2,855 microsatellites on 22 autosomes, were simulated for 1,497 individuals in 23 families. Phenotype data and sequence data for seven candidate genes were provided for 1,000 of these individuals who were "living" and available for study. Data were simulated for 50 replicate samples in each of two populations, a general population and a population isolate formed from a small group of founders.

Adolescent↗

Virtual bronchoscopy.

Virtual bronchoscopy is rapidly providing a software solution for visualization and measurement of the human airway tree with data derived from multirow detector X-ray CT scans as the most common data source. Increasingly, other imaging data sources to create three-dimensional image renderings of the bronchial tree are being used including magnetic resonance imaging, ultrasound, and the digital color image taken by the bronchoscope itself. Software solutions now exist for providing simple renderings of the bronchial tree through which a fly-through of the airway lumen by the center line of the airway can be added (the fly-through mimics the view that a real flexible bronchoscope affords the operator). The images so produced are visually accurate (i.e., they appear very realistic) and with good software now available are also analytically correct (i.e., measurements taken from these images are accurate). More advanced virtual bronchoscopic applications, including image-based pathfinding to mediastinal and peripheral lung structures, are also in development. Synergistic datasets composed of image data from multiple image sources are also being developed.

Bronchial Diseases↗