Search results for "informatics"

Design Issues and Sample Size when Exposure Measurement is Inaccurate

2001

AbstractMeasurement error often leads to biased estimates and incorrect tests in epidemiological studies. These problems can be corrected by design modifications which allow for refined statistical models, or in some situations by adjusted sample sizes to compensate a power reduction. The design options are mainly an additional replication or internal validation study. Sample size calculations for these designs are more complex, since usually there is no unique design solution to obtain a prespecified power. Thus, additionally to a power requirement, an optimal design should also fulfill the criteria of minimizing overall costs. In this review corresponding strategies and formulae are descr…

Quantifying stenosis in renal arteriograms: a fuzzy syntactic analysis.

1999

AbstractThe introduction of fuzzy logic improves a system for the automatic quantification of renal artery lesions seen in digital subtraction angiograms. A two-step approach has been followed. An earlier system based on non-fuzzy syntactic analysis provided a clear symbolic description of the stenotic lesions. Although this system worked correctly, it did not take into account the variability and uncertainty inherent to image processing and to knowledge on the reference diameter. This system has been improved by the introduction of fuzzy logic in the representation of the reference diameter. It provides a description of the stenosis in terms of fuzzy quantities. To illustrate the benefits …

Reference Standards for Software Evaluation

1990

AbstractThe field of automated ECG analysis was one of the earliest topics in Medical Informatics and may be regarded as a model both for computer-assisted medical diagnosis and for evaluating medical diagnostic programs. The CSE project has set reference standards of two kinds: In a broad sense, a standard how to perform a comprehensive evaluation study, in a narrow sense, standards as specific references for evaluating computer ECG programs. The evaluation methodology used within the CSE project is described as a basis for presentation of results which are published elsewhere in this issue.

Use of Information from Clinical Trials for an Integrated Cancer Registry

1990

AbstractThe registry of childhood malignancies in the F.R.G. is a combination of a population-based and hospital-based cancer registry. A large amount of the collected data originates from multicenter clinical trials which are integrated into the documentation system of the cancer registry. The paper describes the information flow and the system of data storage which consists of a central database on a departmental system at the registry and of several coordinated peripheral databases on microcomputers at the trial centers. Practical experience shows an increased availability and validity of the data in the registry since the implementation of the system. Aspects of data integrity and secur…

How Do Cancer Registries in Europe Estimate Completeness of Registration?

2008

Summary Objectives: Several methods for estimating completeness in cancer registries have been proposed. Little is known about their relative merits. Before embarking on a systematic comparison of methods we wanted to know which indicators were currently in use and whether there had been comparative investigations of estimation methods. Methods: We performed a survey among European cancer registries asking which methods for estimating completeness they used and whether they had performed comparisons of methods. Results: One hundred and ninety-five European cancer registries were contacted after identification using membership directories of the European Network of Cancer Registries (ENCR) a…

Professional Qualification of German Physicians in Medical Informatics

1994

Abstract:In addition to the medical education in the Federal Republic of Germany which includes a compulsory Medical Informatics course there exists a formal program for professional qualification of physicians in Medical Informatics. After two years of clinical practice and 1.5 years of professional training at an authorized institution, a physician may receive in addition to the medical degree a “supplement Medical Informatics”. The qualification requirements are described in detail. Physicians with the additional Medical Informatics qualification perform responsible tasks in their medical domain and serve as partners for fully specialized Medical Informatics ex-’ perts in the solution of…

Author response: Novel adverse outcome pathways revealed by chemical genetics in a developing marine fish

2016

Calorie Restriction in Mammals and Simple Model Organisms

2014

Calorie restriction (CR), which usually refers to a 20–40% reduction in calorie intake, can effectively prolong lifespan preventing most age-associated diseases in several species. However, recent data from both human and nonhumans point to the ratio of macronutrients rather than the caloric intake as a major regulator of both lifespan and health-span. In addition, specific components of the diet have recently been identified as regulators of some age-associated intracellular signaling pathways in simple model systems. The comprehension of the mechanisms underpinning these findings is crucial since it may increase the beneficial effects of calorie restriction making it accessible to a broad…

Power training and postmenopausal hormone therapy affect transcriptional control of specific co-regulated gene clusters in skeletal muscle

2010

At the moment, there is no clear molecular explanation for the steeper decline in muscle performance after menopause or the mechanisms of counteractive treatments. The goal of this genome-wide study was to identify the genes and gene clusters through which power training (PT) comprising jumping activities or estrogen containing hormone replacement therapy (HRT) may affect skeletal muscle properties after menopause. We used musculus vastus lateralis samples from early stage postmenopausal (50–57 years old) women participating in a yearlong randomized double-blind placebo-controlled trial with PT and HRT interventions. Using microarray platform with over 24,000 probes, we identified 665 diffe…

Regulatory mechanisms of estrogen on vascular ageing

2019

Women can be considered hemodynamically younger than men of the same age, based on epidemiological studies establishing that the incidence of vascular diseases in women is relatively lower compared to that in aged-matched men. However, after menopause, these numbers increase to values that are close to those found in men. Vascular ageing is associated with structural and functional changes of the vascular wall, including endothelial dysfunction, arterial stiffening, and remodelling, as well as impaired angiogenesis, which become major risk factors in the development of cardiovascular disease.