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At least 1,405 records · Page 78Linked to original sources
PubMed2001

Radiological image data migration. Practical experience and comparison of the costs of work.

PURPOSE: To identify costs deriving from data migration of obsolete digital archives by measuring the workload, and to analyse migration-associated problems. MATERIAL AND METHODS: Two digital archives were used (DTL and MOD) and the capacity of these archives could no longer support the needs of the Medical Imaging Centre. The entire content of the DLT archive and selected data from the MOD archive were transferred to the current higher capacity (17 TB) tape archive. The running time of work processes was measured by self-reporting, and the cost of work was calculated. RESULTS: The transfer of 43,096 studies required 314 working hours over the course of 15 months in total. The work was partly manual, partly automatic. The percentage of non-retrievable MOD images was 35. Less than 0.2% of the DLT image transfers failed due to incorrect patient or image data. The MOD - DLT transfer cost was six times higher per study than the DLT - DLT transmission cost. CONCLUSION: At present, data migration may be inevitable as the amount of data increases and technology advances. The data transfer proved to be labour intensive, with high fault sensitivity regarding the MOD archive. The cost of work of data migration was 0.4% of estimated digital archiving total yearly cost. Automated data migration is preferable.

Costs and Cost Analysis↗
PubMed2005

DNA databases.

This paper presents DNA algorithms for five relational algebra database operations, selection, projection, union, set difference, and Cartesian product on so-called DNA databases. A DNA database is a database where data records are encoded as DNA strands. The five operations mentioned before are fundamental in the field of databases and perform most of the data retrieval operations on current databases.

Algorithms↗
PubMed2006

Optimal search strategies for detecting cost and economic studies in EMBASE.

BACKGROUND: Economic evaluations in the medical literature compare competing diagnosis or treatment methods for their use of resources and their expected outcomes. The best evidence currently available from research regarding both cost and economic comparisons will continue to expand as this type of information becomes more important in today's clinical practice. Researchers and clinicians need quick, reliable ways to access this information. A key source of this type of information is large bibliographic databases such as EMBASE. The objective of this study was to develop search strategies that optimize the retrieval of health costs and economics studies from EMBASE. METHODS: We conducted an analytic survey, comparing hand searches of journals with retrievals from EMBASE for candidate search terms and combinations. 6 research assistants read all issues of 55 journals indexed by EMBASE for the publishing year 2000. We rated all articles using purpose and quality indicators and categorized them into clinically relevant original studies, review articles, general papers, or case reports. The original and review articles were then categorized for purpose (i.e., cost and economics and other clinical topics) and depending on the purpose as 'pass' or 'fail' for methodologic rigor. Candidate search strategies were developed for economic and cost studies, then run in the 55 EMBASE journals, the retrievals being compared with the hand search data. The sensitivity, specificity, precision, and accuracy of the search strategies were calculated. RESULTS: Combinations of search terms for detecting both cost and economic studies attained levels of 100% sensitivity with specificity levels of 92.9% and 92.3% respectively. When maximizing for both sensitivity and specificity, the combination of terms for detecting cost studies (sensitivity) increased 2.2% over the single term but at a slight decrease in specificity of 0.9%. The maximized combination of terms for economic studies saw no change in sensitivity from the single term and only a 0.1% increase in specificity. CONCLUSION: Selected terms have excellent performance in the retrieval of studies of health costs and economics from EMBASE.

Data Collection↗
PubMedDate not supplied

Customized medical image databases: a low-cost approach.

The increasing use of digital images in medicine creates a demand for efficient but simple methods to store, retrieve and display images. The ideal solution for this might be a large-scale hospital-integrated picture archiving and communication systems, but this is not applicable under all conditions. A small-scale, user-defined image database running on a desktop computer may fit the individual needs better, while yielding optimal cost-effectiveness. We will present a way to create customized image databases using a general-purpose desktop database system and a specialized, dedicated image handling component programmed in C++.

Cost-Benefit Analysis↗
PubMed2005

A scale space approach for automatically segmenting words from historical handwritten documents.

Many libraries, museums, and other organizations contain large collections of handwritten historical documents, for example, the papers of early presidents like George Washington at the Library of Congress. The first step in providing recognition/ retrieval tools is to automatically segment handwritten pages into words. State of the art segmentation techniques like the gap metrics algorithm have been mostly developed and tested on highly constrained documents like bank checks and postal addresses. There has been little work on full handwritten pages and this work has usually involved testing on clean artificial documents created for the purpose of research. Historical manuscript images, on the other hand, contain a great deal of noise and are much more challenging. Here, a novel scale space algorithm for automatically segmenting handwritten (historical) documents into words is described. First, the page is cleaned to remove margins. This is followed by a gray-level projection profile algorithm for finding lines in images. Each line image is then filtered with an anisotropic Laplacian at several scales. This procedure produces blobs which correspond to portions of characters at small scales and to words at larger scales. Crucial to the algorithm is scale selection, that is, finding the optimum scale at which blobs correspond to words. This is done by finding the maximum over scale of the extent or area of the blobs. This scale maximum is estimated using three different approaches. The blobs recovered at the optimum scale are then bounded with a rectangular box to recover the words. A postprocessing filtering step is performed to eliminate boxes of unusual size which are unlikely to correspond to words. The approach is tested on a number of different data sets and it is shown that, on 100 sampled documents from the George Washington corpus of handwritten document images, a total error rate of 17 percent is observed. The technique outperforms a state-of-the-art gap metrics word-segmentation algorithm on this collection.

Abstracting and Indexing↗
PubMed1996

A database of mutants and effects of site-directed mutagenesis experiments on G protein-coupled receptors.

A database system and computer programs for storage and retrieval of information about guanine nucleotide-binding protein (G protein) -coupled receptor mutants and associated biological effects have been developed. Mutation data on the receptors were collected from the literature and a database of mutants and effects of mutations was developed. The G protein-coupled receptor, family A, point mutation database (GRAP) provides detailed information on ligand-binding and signal transduction properties of more than 2130 receptor mutants. The amino acid sequences of receptors for which mutation experiments have been reported were aligned, and from this alignment mutation data may be retrieved. Alternatively, a search form allowing detailed specification of which mutants to retrieve may be used, for example, to search for specific amino acid substitutions, substitutions in specific protein domains or reported biological effects. Furthermore, ligand and bibliographic oriented queries may be performed. GRAP is available on the Internet (URL: http://www-grap.fagmed.uit.no/GRAP/+ +homepage.html) using the World-Wide Web system.

Amino Acid Sequence↗
PubMed1999

Development and preliminary clinical tests of an impedance sensing VDD recording pacemaker for diagnosis and research.

Episodes of serious but infrequently occurring cardiac arrhythmias can be difficult to detect and analyse, even with modern Holter monitoring. A previous diagnostic pacemaker developed by this group provided VVI pacing therapy and recorded intracardiac ECG signals but had no atrial sensing or impedance measuring capability. A new external diagnostic pacemaker system is described that has been developed to assist in diagnosing intermittent arrhythmias by selectively recording intracardiac signals. Unlike other ambulatory monitors, in addition to recording ECG, the device combines VDD pacing therapy with the capability of monitoring and recording intracardiac impedance and pressure waveforms through a temporary intracardiac lead. A PCMCIA memory card allows storage of 48 arrhythmic events of 21 seconds each. Twelve seconds of waveform are retained before the event occurs and nine seconds after. Data retrieval and processing is performed with a PC which reconstructs each waveform for display. The ECG provides data on cardiac rhythm while cardiac function is inferred from the haemodynamic signals. During simulated trials, 14 event types were presented to the system. All events were successfully detected and recorded. During in vivo clinical tests 83 waveform recordings were made. Impedance fluctuations with typical peak-to-peak values of 64 ohms were successfully recorded.

Arrhythmias, Cardiac↗
PubMed2001

Requirements for an enterprise digital image archive.

This report describes several image archival problems facing the authors' department and the results of their attempt to define the requirements for an enterprise digital image archive. The problems identified include the costs of supporting multiple distinct archives, the increased complexity of supporting multiple archive interfaces, the differences in data handling policies and resulting variations in data integrity, and variability in support for nonimage data. The authors also describe the data collected including image volumes and trends and imaging device trends. Finally, the resulting specification for an enterprise digital image archive, including storage and retrieval performance and interface requirements are presented.

Hospital Costs↗
PubMed1982

Microcomputer applications in retinal research.

A low cost microcomputer was used to: (1) word process and edit this manuscript, (2) create a patient file storage and retrieval system, (3) transcribe and store information from video display such as wide-angle fundus photographs and fluorescein angiograms, (4) plot data points in graphic display mode, (5) solve complex equations used to calculate intraocular tumor volumes, (6) search medical literature data bases, and (7) directly interface with sophisticated laboratory equipment performing complicated tasks such as multicomponent analysis and enzyme kinetics.

Computers↗
PubMed2003

Metric-space indexes as a basis for scalable biological databases.

Biochemical databases will be best served by the development of new specialized database management systems whose storage managers are based on metric-space indexing techniques and the development a database query languages that embody semantics derived from biochemical models of similarity and evolution. Important biochemical data types cannot be effectively mapped to low dimensional coordinate systems on which O(log n) indexing methods rely. It is clear from an abundance of bioinformatic discoveries that biochemical data is not random and exhibits interesting structure with respect to clustering. Metric-space indexing exploits a data set's intrinsic clustering to speed the execution of similarity queries, even when the data cannot be mapped to a coordinate system. Database management systems that seamlessly integrate semantically rich query languages with a metric-storage and retrieval mechanism will allow biologists to simply and concisely develop informatic studies that have traditionally been large and labor intensive.

Computational Biology↗
PubMed1978

Proem to a quantum leap in audiometric data collection and management.

A revolution began in 1961 when Weiss first mated a minicomputer to an audiometer. Today's technology offers a number of aids to the audiometrist in standardizing stimulus presentation patterns, objectifying and validating responses, computing HTL from a response pattern, computing significant threshold shifts from baseline audiograms, computing percentage binaural hearing impairment for a person, etc. Audiometers can be made which self-calibrate and are fail-safe. Furthermore, a revolution has occurred in replacing an audiogram written record, for example a card, with a system in which the audiometer transfers HTL data directly into computer storage without the possibility of transcription error. A group of turnkey and interlocking terminals allows the audiometric data of any individual serviced to be retrieved and/or updated from any terminal in the system. This paper lists commercial models simulating standard manual audiometry, models computerizing Bekesy audiometry, and some experimental models on yet other principles. Psychometric methods and methods for response validation suitable for audiometry are discussed, and out of many possible suggestions a few are offered for audiometric paradigms which may go beyond simulation of ASHA guidelines and ANSI specifications for manual threshold audiometry in order to take advantage of the power available from the computer as a tool in audiometry. For example, a computer can scan the responses of as many as 32 subjects simultaneously, offer each an adaptive program based on his response, and printout HTL's in conventional audiometric format.

Adolescent↗
PubMed1985

Transfer data. A proposed international standard for interlaboratory information exchange.

Clinical laboratory information is composed of descriptive terms and corresponding codes that define patients, specimens, and tests. These basic units of information, or data elements, assume literal character content and sequences in clinical laboratory computer files and messages. The growing international use of computers for scientific data transfer highlights the need for standardized coding conventions that eliminate the ambiguities of language and scientific terminology. An international symposium of the Commission on World Standards of the World Association of Societies of Pathology recommends that international consensus standards be developed to insure the accurate transfer of scientific data between clinical laboratory computers while maintaining strict subject confidentiality. It is anticipated that such standards would be widely applicable to the storage and retrieval of medical information in computers throughout the world.

Computers↗
PubMed2006

GenePING: secure, scalable management of personal genomic data.

BACKGROUND: Patient genomic data are rapidly becoming part of clinical decision making. Within a few years, full genome expression profiling and genotyping will be affordable enough to perform on every individual. The management of such sizeable, yet fine-grained, data in compliance with privacy laws and best practices presents significant security and scalability challenges. RESULTS: We present the design and implementation of GenePING, an extension to the PING personal health record system that supports secure storage of large, genome-sized datasets, as well as efficient sharing and retrieval of individual datapoints (e.g. SNPs, rare mutations, gene expression levels). Even with full access to the raw GenePING storage, an attacker cannot discover any stored genomic datapoint on any single patient. Given a large-enough number of patient records, an attacker cannot discover which data corresponds to which patient, or even the size of a given patient's record. The computational overhead of GenePING's security features is a small constant, making the system usable, even in emergency care, on today's hardware. CONCLUSION: GenePING is the first personal health record management system to support the efficient and secure storage and sharing of large genomic datasets. GenePING is available online at http://ping.chip.org/genepinghtml, licensed under the LGPL.

Confidentiality↗
PubMed1993

Natural language processing of asthma discharge summaries for the monitoring of patient care.

A technique for monitoring healthcare via the processing of routinely collected narrative documentation is presented. A checklist of important details of asthma management in use in the Glasgow Royal Infirmary (GRI) was translated into SQL queries and applied to a database of 59 GRI discharge summaries analyzed by the New York University Linguistic String Project medical language processor. Tables of retrieved information obtained for each query were compared with the text of the original documents by physician reviewers. Categories (unit = document) were: (1) information present, retrieved correctly; (2) information not present; (3) information present, retrieved with minor or major error; (4) information present, retrieved with minor or major omissions. Category 2 (physician "documentation score") could be used to prioritize manual review and guide feedback to physicians to improve documentation. The semantic structuring and relative completeness of retrieved data suggest their potential use as input to further quality assurance procedures.

Asthma↗
PubMed1997

Automating and improving the data quality of a nursing department quality management program at a university hospital.

BACKGROUND: The development and implementation of a relational database program for nursing quality management at a university hospital was stimulated by a lack of consistent data management and analysis tools in the existing noncomputerized program. PROGRAM DEVELOPMENT AND IMPLEMENTATION: An initial software prototype implemented in the critical care service included data collection instruments for five areas: medication errors, patient falls, returns to an intensive care unit within 48 hours, hospital-acquired skin breakdown, and unplanned extubations. Access to the database was limited and paper reports only were disseminated on a scheduled basis. In a second phase, the database is being deployed throughout the nursing department using a local area network. Nurse managers will enter and interact with the quality database online and have access to graphics, reports, and action plan development. POSSIBLE ERRORS: A wide range of potential errors influences decisions on how to collect, store, retrieve, and process quality management data. Each type of error affects the nurse manager's ability to identify significant patterns or trends that are amenable to intervention. There is no right way of constructing and implementing a quality improvement database; only an optimum balance between cost, complexity, and efficacy. SUMMARY AND CONCLUSIONS: Initial feedback from end uses has been positive. A three-year experience with a personal computer database suggests that the personal computer-based information technology is appropriate for small to medium applications and can support departmentwide CQI efforts. A case scenario using simulated data is included to illustrate the use of computerized reports in assessing and taking action on an increase in falls.

Accidental Falls↗
PubMed2006

Terminated Ramp-Support vector machines: a nonparametric data dependent kernel.

We propose a novel algorithm, Terminated Ramp-Support Vector Machines (TR-SVM), for classification and feature ranking purposes in the family of Support Vector Machines. The main improvement relies on the fact that the kernel is automatically determined by the training examples. It is built as a function of simple classifiers, generalized terminated ramp functions, obtained by separating oppositely labeled pairs of training points. The algorithm has a meaningful geometrical interpretation, and it is derived in the framework of Tikhonov regularization theory. Its unique free parameter is the regularization one, representing a trade-off between empirical error and solution complexity. Employing the equivalence between the proposed algorithm and two-layer networks, a theoretical bound on the generalization error is also derived, together with Vapnik-Chervonenkis dimension. Performances are tested on a number of synthetic and real data sets.

Algorithms↗
PubMed2004

HeiDATAProVIT-Heidelberg data archiving, tag assembling, processing and visualization tool.

The demands that have to be met by software tools for biomedical data evaluation strongly differ depending on the background of their application. In clinical routine emphasis is placed on ease of handling and application of standardized procedures, whereas in biomedical research the main focus lies on flexibility and extensibility. These contradictory requirements are reflected by the design principles of existing software solutions: programs for routine application are barely extensible or modifiable by the user and the complexity of highly flexible data processing tools for research purposes hampers the application of new methods to larger data volumes. This gap poses technical difficulties to the transfer of methods from research into clinical routine. The software we present in this paper bridges this discrepancy by incorporating two different levels of application. The lower level offers options to integrate custom written MATLAB((R)) processing routines and to add new evaluation schemes to a pool of existing procedures. The higher level allows for performing standard evaluations by accessing and applying these previously defined procedures. Four basic concepts were introduced to ensure that the program is both maximally flexible on a lower level and readily applicable on a higher level: the tag concept, the concept of modularized visualization, the dummy file concept, and the batchjob concept. These concepts are the key to flexibly assemble and apply the three universal stages of data evaluation: (1) archiving of acquired data, (2) processing the data using signal processing algorithms and (3) visualizing the results in appropriate graphical formats. The present paper illustrates the four concepts within the two levels of the software architecture. The basic functionality and usefulness of the program are demonstrated using an evaluation of gait analysis data as sample application. In summary, this software tool closely integrates a database for biomedical datasets and an extensible pool of evaluation and visualization procedures realized using MATLAB((R)). It is well suited both for data processing in clinical routine and for evaluation of measurement data in any medical research project.

Information Storage and Retrieval↗