Search results for "Validation Studies as Topic"
showing 8 items of 8 documents
Accounting for haplotype phase uncertainty in linkage disequilibrium estimation
2007
The characterization of linkage disequilibrium (LD) is applied in a variety of studies including the identification of molecular determinants of the local recombination rate, the migration and population history of populations, and the role of positive selection in adaptation. LD suffers from the phase uncertainty of the haplotypes used in its calculation, which reflects limitations of the algorithms used for haplotype estimation. We introduce a LD calculation method, which deals with phase uncertainty by weighting all possible haplotype pairs according to their estimated probabilities as evaluated by PHASE. In contrast to the expectation-maximization (EM) algorithm as implemented in the HA…
Are analysts doing method validation in liquid chromatography?
2014
International audience; Method validation is being applied in the reported analytical methods for decades. Even before this protocol was defined, authors already somehow validated their methods without full awareness. They wished to assure the quality of their work. Validation is an applied approach to verify that a method is suitable and rugged enough to function as a quality control tool in different locations and times. The performance parameters and statistical protocols followed throughout a validation study vary with the source of guidelines. Before single laboratory validation, an analytical method should be fully developed and optimized. The purpose of the validation is to confirm p…
Dietary methods and biomarkers of omega 3 fatty acids: a systematic review
2012
The aims of the present study were to review the validity of dietary methods used to measure the usual long chain (LC) omega-3 polyunsaturated fatty acid (n-3 PUFA) intake of a population and to assess the usefulness of different biomarkers ofn-3 PUFA in healthy humans. Two systematic literature searches were conducted until May 2011 to update previous systematic reviews. The first literature search aimed to find studies validating the methodology used for measuring the dietary intake ofn-3 PUFA. The second search aimed to find human intervention studies in whichn-3 PUFA status changed after 2 weeks ofn-3 PUFA supplementation. Sixteen studies were identified for inclusion in the first revie…
Validación y verificación analítica de los métodos microbiológicos
2015
Clinical microbiologists should ensure, to the maximum level allowed by the scientific and technical development, the reliability of the results. This implies that, in addition to meeting the technical criteria to ensure their validity, they must be performed with a number of conditions that allows comparable results to be obtained, regardless of the laboratory that performs the test. In this sense, the use of recognized and accepted reference methodsis the most effective tool for these guarantees. The activities related to verification and validation of analytical methods has become very important, as there is continuous development, as well as updating techniques and increasingly complex …
Dose calculation in biological samples in a mixed neutron-gamma field at the TRIGA reactor of the University of Mainz
2010
To establish Boron Neutron Capture Therapy (BNCT) for non-resectable liver metastases and for in vitro experiments at the TRIGA Mark II reactor at the University of Mainz, Germany, it is necessary to have a reliable dose monitoring system. The in vitro experiments are used to determine the relative biological effectiveness (RBE) of liver and cancer cells in our mixed neutron and gamma fi eld. We work with alanine detectors in combination with Monte Carlo simulations, where we can measure and characterize the dose. To verify our calculations we perform neutron fl ux measurements using gold foil activation and pin-diodes . Material and methods . When L- α -alanine is irradiated with ionizing …
Physical Activity Level Using Doubly-Labeled Water in Relation to Body Composition and Physical Fitness in Preschoolers
2018
Background and objectives: There is a lack of studies investigating associations of physical activity level (PAL) and activity energy expenditure (AEE) using the doubly-labeled water (DLW) method with body composition and physical fitness in young children. Thus, we aimed to examine cross-sectional associations of PAL and AEE with body composition indices and physical fitness components in Swedish preschool children. Materials and methods: PAL was calculated as total energy expenditure measured using DLW divided by the predicted basal metabolic rate in 40 children aged 5.5 (standard deviation 0.2) years. AEE was calculated as total energy expenditure minus basal metabolic rate and the therm…
Maximum forces acting on the abdominal wall: Experimental validation of a theoretical modeling in a human cadaver study
2011
Incisional hernias following median laparotomy have a high incidence and recurrence rate after repair, so that a better understanding of the linea alba biomechanics is desirable. The mechanical stress exerted on the linea alba in living humans is primarily generated by the musculature. In this human cadaver study, intraabdominal pressure was simulated by insertion of a balloon that was increasingly filled to maximal pressures of 200 mbar. The related forces acting transversely on the linea alba at maximum pressure were found to be between 41.6 and 52.2 N/cm (mean = 45.9 N/cm), which is in agreement with a recent modeling of the related forces.
Convergent and discriminative validity of the Frail-VIG index with the EQ-5D-3L in people cared for in primary health care
2021
Abstract Background The Frail-VIG frailty index has been developed recently. It is an instrument with a multidimensional approach and a pragmatic purpose that allows rapid and efficient assessment of the degree of frailty in the context of clinical practice. Our aim was to investigate the convergent and discriminative validity of the Frail-VIG frailty index with regard to EQ-5D-3L value. Methods We carried out a cross-sectional study in two Primary Health Care (PHC) centres of the Catalan Institute of Health (Institut Català de la Salut), Barcelona (Spain) from February 2017 to January 2019. Participants in the study were all people included under a home care programme during the study peri…