Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Software Validation”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 181 records · Page 10Linked to original sources
PubMed1996

Dynamic circular buffering: a technique for equilibrium gated blood pool imaging.

We have devised a software technique called "dynamic circular buffering" (DCB) with which we create a gated blood pool image sequence of the heart in real time using the best features of LIST and FRAME mode methods of acquisition/processing. The routine is based on the concept of independent "agents" acting on the timing and position data continuously written into the DCB. This approach allows efficient asynchronous operation on PC-type machines and enhanced capability on systems capable of true multiprocessing and multithreading.

Gated Blood-Pool Imaging↗
PubMed1992

EndoCyte, an interactive computer program for quantitative analysis of receptor-mediated endocytosis.

We present EndoCyte, a user friendly interactive program for quantitative analysis of receptor-mediated endocytosis. The data, comprised of time-dependent concentrations of the ligand at the cell surface and the ligand internalized by cells, are analyzed by the application of a set of nested mathematical models of endocytosis. EndoCyte reduces data to parameters conventional in description of receptor-mediated endocytosis and a parameter which describes the non-linear effects. The performance of EndoCyte is documented by the analysis of applications to synthetic data.

Computer Simulation↗
PubMed1995

The LBI-method for automated indexing of diagnoses by using SNOMED. Part 2. Evaluation.

We present a simple, formal, lexicon-based method for automated indexing of diagnoses based on the Systematized Nomenclature of Medicine (SNOMED), called LBI-method. Part 1 gave an introduction to the LBI-method and presented its realisation as application system SALBIDH. Part 2 presents the design and the results of an evaluation study to judge the quality of the LBI-method. In this evaluation study the quality of automated indexing as well as the quality of the retrieval of patient data by using automated indexed diagnoses was examined. The results show that the retrieval based on SNOMED indices is at least as good as the retrieval based on ICD classes despite a lot of indexing errors. From this we gather that our system is not yet good enough for immediate routine use but that an appropriate indexing quality and, as a result, a higher retrieval quality can be achieved after few improvements of the LBI-method, especially after revision of the lexicons.

Abstracting and Indexing↗
PubMed1994

Clinical workstations: identifying clinical requirements and understanding clinical information.

A preliminary exploration of the problem of defining and meeting users' needs, this paper draws the bulk of its content from experiences in the PEN&PAD project in the UK. This program has been researching and developing prototype clinical workstations for direct use in patient care by health care professionals, chiefly doctors. Focusing more on general issues rather than the specific functional requirements embodied in the PEN&PAD prototypes, the paper begins with a brief summary of the goals of PEN&PAD and then outlines the three main axes of the work: user-centred design, medical concept and medical record models, and user interfaces and architectures. The remainder of the paper then concentrates on the first of these topics--working with users to define functional requirements.

Computer Systems↗
PubMed1994

Major issues in user interface design for health professional workstations: summary and recommendations.

Lack of good user interfaces has been a major impediment to the acceptance and routine use of health-care professional workstations. Health-care providers, and the environment in which they practice, place strenuous demands on the interface. User interfaces must be designed with greater consideration of the requirements, cognitive capabilities, and limitations of the end-user. The challenge of gaining better acceptance and achieving widespread use of clinical information systems will be accentuated as the variety and complexity of multi-media presentation increases. Better understanding of issues related to cognitive processes involved in human-computer interactions is needed in order to design interfaces that are more intuitive and more acceptable to health-care professionals. Critical areas which deserve immediate attention include: improvement of pen-based technology, development of knowledge-based techniques that support contextual presentation, and development of new strategies and metrics to evaluate user interfaces. Only with deliberate attention to the user interface, can we improve the ways in which information technology contributes to the efficiency and effectiveness of health-care providers.

Cognition↗
PubMed1994

Automated metrics for user interface design and evaluation.

Automated metrics will allow user interfaces to be partially evaluated early in the development process. They allow potential problems to be identified and corrected prior to user testing, saving both time and money. As a result, improved interfaces can be developed without additional costs. Both task-independent and task-sensitive automated metrics appear promising. Task-independent metrics should prove most useful for predicting user preferences and somewhat useful for predicting user performance. Task-sensitive metrics should prove useful for predicting both user preferences and performance. Several metrics are introduced and research directions are discussed.

Computer Systems↗
PubMed1994

New opportunities for processing the OSI-7 layer protocols using parallel processing (transputers).

The attractiveness of the OSI-7 layer model is closely dependent upon a highly ambitious intent to promote a series of quasi-universal standards to coordinate the communication between heterogeneous applications, whatever the distributed architectures might be. However, a major criticism of the OSI-model is the performance and the handling of the presentation layer. This paper deals with the evaluation of parallel processing techniques operating at the upper levels of the OSI-model using transputers in a parallel co-processor. It is shown that the performance problem is highly dependent on the structure of the protocol stack and its implementation. With the object-oriented modularization of the protocol stack, an architecture of a possible co-processor using transputers is considered and its performance is considered adequate. An ideal configuration is briefly presented. A final performance appraisal of the parallelism effect is discussed with some insight into the future.

Computer Communication Networks↗
PubMed1996

A Dutch medical language processor.

This paper describes the current state of a medical language processor for Dutch. The goal is to implement a language specific front-end compatible with some existing applications that aim at the intelligent extraction and processing of information from patient discharge summaries. A complete chain for processing and understanding Dutch medical documents will be the ultimate result. The text focuses mainly on the language specific aspects of the language processing chain. Evaluation results of the already functioning components are given as well as an outline for future developments and enhancements. A short theoretical background is provided (cf. also [1-3]: Rossi Mori et al., Proc. SCAMC 90, 1990, pp. 185-189; Wingert, in: Informatics and Medicine, an advanced course, Springer-Verlag. 1977, pp. 579-646; Wingert, Proc. MEDINFO 80, 1980, pp. 1321-1331) before the description of each component in order to familiarise the non-experienced reader with the basic notions of computational linguistics.

Artificial Intelligence↗
PubMed1996

Relationship of vascular thrombosis and inflammatory leukocyte infiltration to neointimal growth following porcine coronary artery stent placement.

BACKGROUND: Superficial and intramural thrombosis are reproducible histopathological features of the porcine coronary oversized stent injury model. Fibrin and its degradation products are chemotactic for mononuclear leukocytes, and promote the proliferation and migration of vascular smooth muscle cells (VSMC) in vitro. The goal of this study was to quantitate the serial histomorphologic evolution of thrombosis, leukocyte infiltration, VSMC proliferation and collagen accumulation following porcine coronary artery stent placement in a porcine model. METHODS: Twenty-four normocholesterolemic swine underwent oversized balloon (3.5-4.0 mm) coronary angioplasty and tantalum metal stent placement. Twenty-six different arterial sites were injured, followed by serial sacrifice at day 4 (n = 6), 8 (n = 6), 14 (n = 6), and 28 (n = 6). Quantitative analysis of the neointima was performed using a high resolution video-microscopy interface and a validated histomorphometric software program. Alpha actin-positive VSMC density (per 10(4) micro(2) neointimal area) and collagen-specific picro-sirius red fluorescence (percent of neointima) were quantitated at sites adjacent to and distant from coronary artery stent placement. RESULTS: The percent of total neointimal area occupied by resolving thrombus material was greater at days 4-8 compared to 14-28 days (59-63% vs. 1-2%; P = 0.001). Mononuclear leukocytes were also significantly increased at days 4 and 8 (92 +/- 1 and 70 +/- 8%) compared to days 14-28 (both 3 +/- 3%; P = 0.001), as a percentage of the total neointimal cellularity. Total neointimal cell density did not change (20 +/- 10, 12 +/- 6, 23 +/- 7 and 20 +/- 3 cells/10(4) micro(2); P-value, NS), despite progressive cross-sectional vascular area stenosis reduction from 7 +/- 3% at day 4 to 72 +/- 14% at day 28 (P = 0.001). Percent neointimal fibrinoid thrombus content and mononuclear leukocyte cellularity were correlated in this model (R = 0.81; P < 0.001). Peri-stent neointimal collagen staining exceeded that at vascular sites distant from porcine coronary stent placement by 14 days (29 +/- 6 vs. 15 +/- 3%), and remained greater at 28 days (35 +/- 11 vs. 16 +/- 12%) (both P < 0.05). CONCLUSIONS: Quantitative serial histomorphometry of porcine coronary vascular stent delivery sites demonstrates early (4-8 day) neointimal mononuclear leukocyte infiltration which is histomorphologically and temporally related to intramural fibrinoid thrombosis. Significant vascular stenosis and collagen deposition occurs by 14-28 days at these vascular injury sites. These data suggest a local interaction between thrombotic and inflammatory elements in porcine coronary neointima following oversized stent injury.

Angioplasty, Balloon↗
PubMed1992

Impact on the management and delivery of primary health care by a computer-based information system.

Timely and accurate information forms the basis for management to plan and for care providers to take appropriate action. We report from a developing country a research project aimed to strengthen the information infrastructure with a computer at a Primary Health Centre. The software (MCHS) was designed to assist the care providers in the information management for the Maternal and Child Health (MCH) programme activities. In Phase I, a baseline survey was conducted to identify the needs and target groups. In Phase II, the MCHS was integrated into routine delivery of MCH to monitor the target population and help in evaluation. The research project's impact is reflected in enhanced utilization of services and quality in care, as seen by reduction of dropouts from the immunization program. In economic terms, we see that the costs for a fully immunised child are reduced with reduction of dropouts; thus, the computer system contributes to quality assurance and cost effectiveness in delivery of care.

Adolescent↗
PubMedDate not supplied

Using the job-exposure matrix for elaborating job histories.

A first software (JHS) for the elaboration of job histories oriented toward risks was designed and results published In an article "A software for the elaboration of Job Histories". This article presents a second software (JES), based on the use of a job-exposure matrix designed for one company. The matrix is essentially a database, an organized gathering of information concerning the company. The two softwares are inter-faced and both run on a PC. When properly exploited, the two softwares can serve as an asset for epidemiological studies dealing with occupational health.

Database Management Systems↗
PubMedDate not supplied

Computer-assisted rheological evaluation of microsamples of mucus.

Dynamic viscoelasticity measurements are required in many studies on biological fluids and they can be performed by determining the corresponding strain when a sinusoidal shear stress is applied to a sample. In several circumstances the amount of fluid that can be obtained for analysis in physiological conditions does not exceed microliters. In this context, the microrheometer technique is a useful approach to determine the dynamic rheological profile of the samples. However, the manual calculation of the desired parameters is tedious and time-consuming. This paper describes a menu-oriented program in order to facilitate its use by non-experts. The comparison between manual and computer-aided calculations demonstrated that the program reduced the time of measurement, and reduced intra- and interobserver variations. The program was developed on an IBM compatible PC in Microsoft C 5.1, and tested in a blind study to check the advantages in terms of time and reproducibility of the system verified by the concordance of two independent observers (interobserver influence) in two different occasions (intraobserver influence).

Bronchi↗
PubMedDate not supplied

The determination of the absolute bioavailability for drug substances with long elimination half-lives (with PC-programs for the method of truncated areas).

A survey is given of the methods for the determination of the absolute bioavailability for drug substances with long elimination half-lives. All methods depend on the assumption of linear pharmacokinetics. Emphasis is laid on Urso and Aarons' regression method of truncated areas-under-the-curve (AUC) to obtain estimates of the absolute bioavailability, F, and the absorption rate constant, ka, without obeying the otherwise general rule of following blood or plasma levels for at least three times the terminal half-life. It is shown by simulation when the linear and when the logarithmic trapezoidal rule is to be used for the calculation of the AUC. Two PC-programs for the regression method of truncated areas are presented: one program (SIMF&KA.EXE) simulates, based on tentative pharmacokinetic parameters, whether a blood sampling scheme, together with the precision of the analytical assay, is adequate to obtain accurate and precise estimates of F and ka; the method is insensitive to large variations in the tentative value of the elimination half-life. The other program (ESTF&KA.EXE) provides estimates of F and ka, with standard deviations of the estimates, from empirical data.

Biological Availability↗
PubMedDate not supplied

A scanning system for digital analysis of cineangiography films.

A system for scanning and digital analysis of cinefilms is presented and its performance is compared with entirely digital radiographic equipment. Apart from the difference between logarithmic and linear gray-scale representation, a higher noise level was found in the scanning system. When its spatial resolution was assessed visually, it was comparable to that of the digital system, although lower than when the cinefilming and scanning steps were evaluated separately. Algorithms for the correction of varying exposure and geometric ("pin-cushion") distortion are also presented. It is concluded that digital analysis after scanning of cinefilms can be a useful alternative to completely digital cineradiographic studies.

Algorithms↗
PubMed1992

Computer quantitation of saturation impairment time as an index of oxygenation during sleep.

The measurement of oxygenation during sleep has become a standard procedure in the assessment of hypoxemia in patients with various disorders. However, an accepted method for quantitating this hypoxemia is not available. This study describes the development of computerized data acquisition and analysis programs to quantitate nocturnal hypoxemia in patients with sleep and breathing disorders. The acquisition program samples the voltage output from pulse oximeters used to measure oxyhemoglobin saturation (SpO2) and stores this on an IBM PC or compatible computer. The analysis program integrates the SpO2 over time below the patient's pretest baseline as well as the integral below 90, 80, 70, 60 and 50% saturation. We refer to each integral as Saturation Impairment Time or SIT. In order to compare these integrals between patients or between the same patient but different studies, the integral is divided by the total sleep study time. We refer to each of these integrals, corrected for sleep study time, as the SIT index. Evaluation of the SIT index in 10 consecutive patients referred for various sleep disorders revealed acquisition program detection and deletion of 48 of 57 (86%) oximeter probe artifacts (mean duration of 3 seconds for undetected artifacts). There were no significant artifacts in the analysis program calculation of the SIT index in these same patients. In conclusion, computer programs were developed to measure and quantitate oxygen saturation measured by oximeters. Preliminary results reveal an accuracy of measurement which should prove acceptable in further clinical evaluations.

Diagnosis, Computer-Assisted↗
PubMed1992

EMSA: a SAAM service for the estimation of population parameters based on model fits to identically replicated experiments.

This paper presents a new technique for the aggregation of models to produce population parameter estimates based on a set of identically replicated experiments. After describing the theoretical basis for the technique we discuss tactical and strategic issues associated with its implementation in the SAAM software. Finally, we demonstrate its utility in the aggregation of models fitted to four simulated experiments.

Algorithms↗
PubMed1992

Intuitive user interfaces (IUI): a CASE starting point for design and programming.

The acceptance of a software product depends to a considerable extent on the user interface. The class of graphic-oriented user interfaces that are called Intuitive User Interfaces (IUI) is described. These interfaces allow the user to learn to operate software programs quickly. In the following the graphical layout put to use in an IUI is elaborated. All images the layout consists of are created with the aid of a paint program. Using these images, a procedure for creating, programming and linking an IUI to software applications is discussed and recommendations are made concerning software and hardware demands for easily creating IUIs. Practical experience of the authors with this procedure, mainly in the medical area, is described.

Computer Graphics↗