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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↗

[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↗

Post-integration of a tumor documentation system into a HIS via middleware.

Integrating autonomous applications is a difficult task since they usually represent similar informations in different data schemes. Any communication requires an agreement of sender and receiver on a common data representation. The number of interfaces to convert one data representation into another is minimized if all participants of an information system agree on one data representation such as Health Level Seven (HL7) or Edifact. Even more convenient is the use of a middleware solution like the Distributed Healthcare Environment (DHE) that keeps message transfer completely transparent to the integration process. This paper discusses a project that aims at the integration of a cancer registry system into a DHE based Hospital Information System (HIS). The project is a cooperation between the universities of Giessen and Magdeburg within the framework of the European Communities Telematics Research Project HC 1019 HANSA (Healthcare Advanced Networked System Architecture). The concept of a so called 'DHE-Adapter' to integrate existing legacy systems is explained. This adapter converts a data or message format of a legacy system into calls of the DHE programming interface. To develop a DHE-Adapter for our cancer registry system we intend to design a DHE-Adapter-Generator which would be able to produce DHE-Adapters for different systems and export formats, e.g. HL7 or Edifact. That would allow a variety of software vendors to integrate their products into the DHE without entering deeply into the DHE's programming interface.

Computer Communication Networks↗

Social deprivation and tooth decay in Scottish schoolchildren.

OBJECTIVES: To quantify the association between dental decay in Scottish Schoolchildren & social deprivation as measured by the Carstairs Index from the 1991 census. DESIGN: An ecological study using data from the Scottish Health Boards Dental Epidemiology Programme and The Public Health Common Data set. SETTING: Scottish Health Boards from 1992-3 to 1994-5. SUBJECTS: Random samples of 5,920 five-year-olds, 5,344 12-year-olds and 6,007 14-year-olds across the 15 Health Boards in Scotland. RESULTS: Positive correlations were demonstrated in all age groups; 12-year-olds (r = 0.72) in 1992-3, 5-year-olds (r = 0.8) in 1993-4 and 14-year-olds (r = 0.55) in 1994-5. Dental decay in all age groups was positively and significantly associated with deprivation as measured by the Carstairs index. CONCLUSION: Tooth decay was confirmed as a disease associated with social deprivation in Scotland. The increasing polarisation of decay to socio-economically deprived groups of the population, suggests a 'whole population' approach such as water fluoridation would prevent tooth decay in these deprived groups most effectively. Nevertheless all evidence-based interventions should be used to try to narrow the "Dental Health Divide' by improving the dental health of deprived individuals.

Adolescent↗

A meta-analysis of the effect of glucagon-like peptide-1 (7-36) amide on ad libitum energy intake in humans.

Seven studies have now been published pertaining to the acute effect of iv administration of glucagon-like peptide-1 (7-36) amide on ad libitum energy intake. In four of these studies energy intake was significantly reduced following the glucagon-like peptide-1 infusion compared with saline. In the remaining studies, no significant effect of glucagon-like peptide-1 could be shown. Lack of statistical power or low glucagon-like peptide-1 infusion rate may explain these conflicting results. Our aim was to examine the effect of glucagon-like peptide-1 on subsequent energy intake using a data set composed of subject data from previous studies and from two as yet unpublished studies. Secondly, we investigated whether the effect on energy intake is dose dependent and differs between lean and overweight subjects. Raw subject data on body mass index and ad libitum energy intake were collected into a common data set (n = 115), together with study characteristics such as infusion rate, duration of infusion, etc. From four studies with comparable protocol the following subject data were included if available: plasma concentrations of glucagon-like peptide-1, subjective appetite measures, well-being, and gastric emptying rate of a meal served at the start of the glucagon-like peptide-1 infusion. Energy intake was reduced by 727 kJ (95% confidence interval, 548-908 kJ) or 11.7% during glucagon-like peptide-1 infusion. Although the absolute reduction in energy intake was higher in lean (863 kJ) (634-1091 kJ) compared with overweight subjects (487 kJ) (209-764 kJ) (P = 0.05), the relative reduction did not differ between the two groups (13.2% and 9.3%, respectively). Stepwise regression analysis showed that the glucagon-like peptide-1 infusion rate was the only independent predictor of the reduction in energy intake during glucagon-like peptide-1 (7-36) amide infusion (r = 0.4, P < 0.001). Differences in mean plasma glucagon-like peptide-1 concentration on the glucagon-like peptide-1 and placebo day (n = 43) were related to differences in feelings of prospective consumption (r = 0.40, P < 0.01), fullness (r = 0.38, P < 0.05), and hunger (r = 0.26, P = 0.09), but not to differences in ad libitum energy intake. Gastric emptying rate was significantly lower during glucagon-like peptide-1 infusion compared with saline. Finally, well-being was not influenced by the glucagon-like peptide-1 infusion. Glucagon-like peptide-1 infusion reduces energy intake dose dependently in both lean and overweight subjects. A reduced gastric emptying rate may contribute to the increased satiety induced by glucagon-like peptide-1.

Adult↗

Sentinel practices in dentistry: a preliminary evaluation.

The objectives of this study were to compare the socioeconomic make-up and the dental caries and dental treatment patterns of a general dental practice (GDP) population of five-year-old children with those of the total resident population of five-year-old children in a specific locality, and, secondly, to examine the process of gathering information on oral healthcare needs in primary dental care. The study was set in Halton, North Cheshire. Data were collected retrospectively from the patient records of four GDP sentinel' practices using a common data abstraction form. The socioeconomic profiles of the GDP population and the 1995/6 NHS child dental health survey population were compared using the Super Profiles geodemographic classification by plotting frequency distributions. The dmft of each population was compared by calculating 95% confidence intervals. The GDP population showed a slight over-representation in the more affluent groupings of the Super Profiles Lifestyle categories and a more dramatic under-representation in two of the more deprived groupings. The confidence intervals for dt and dmft of the GDP data did not include the mean figures produced by the NHS survey, indicating a significant difference at the P < 0.05 level. These differences may be accounted for by the differences in the socioeconomic make-up of the two populations. Local practice policies on patient selection may also have a consequential effect on population disease estimates derived from primary dental care. Data on population disease experience from primary dental care could only be produced by hand-sorting through patient records, which was time-consuming and inefficient. Standardised electronic systems will need to be developed to make GDP data-collection a viable proposition. Information from primary dental care has the potential to make a major contribution to locality oral health needs assessment and it should be seen as being complementary to information gathered from epidemiological surveys.

Child, Preschool↗

A general software package for the handling of medical images.

PICS (portable imaging computer software), is a software system designed for handling and processing a variety of types of medical image. It has been designed to satisfy the following criteria: (a) the software should be portable between different items of hardware with minimal alteration; (b) there should be a simple operator interface to enable use by inexperienced users, while avoiding the need for experienced users to be directed through tedious menu trees; (c) the programming environment should enable simple integration of new data handling protocols. To meet these requirements the software was written in FORTRAN using structured subroutine organization. The software has basic image handling and processing facilities and contains a comprehensive set of nuclear medicine clinical protocols. Other facilities include alignment of images from different modalities with display of superimposed images and ability to handle, analyse and display three-dimensional data sets. Data transfer programs have been written to capture data from gamma camera, CT, MRI, ultrasound and radiographs by converting the images to a common data format. The system provides a hospital with a central digital image handling resource, enabling investigation of the value of digital image processing in potential clinical applications.

Diagnostic Imaging↗

TopDraw: a sketchpad for protein structure topology cartoons.

SUMMARY: Protein topology cartoons are a representation of structural data commonly used by structural biologists to illustrate the relationship between one-dimensional sequence and three-dimensional structural data in a convenient two-dimensional format. TopDraw is a simple, freely available TCL/Tk based drawing program designed specifically for the production of publication quality topology cartoons in a style commonly presented by structural biologists. AVAILABILITY: TopDraw is freely available under the terms of the GNU General Public License. It can be downloaded from http://stein.bioch.dundee.ac.uk/~charlie/scripts/topdraw.html.

Amino Acid Sequence↗