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Validation Process (validation + process)
Selected AbstractsValidation of the Mayo Dysphagia QuestionnaireDISEASES OF THE ESOPHAGUS, Issue 3 2007A. B. M. Grudell SUMMARY., While multiple instruments characterize upper gastrointestinal symptoms, a validated instrument devoted to the measurement of a spectrum of esophageal dysphagia attributes is not available. Therefore, we constructed and validated the Mayo Dysphagia Questionnaire (MDQ). The 27 items of the MDQ underwent content validity, feasibility, concurrent validity, reproducibility, internal consistency, and construct validity testing. To assess content validity, five esophageal subspecialty gastroenterologists reviewed the items to ensure inclusion of pertinent domains. Feasibility testing was done with eight outpatients who refined problematic items. To assess concurrent validity, 70 patient responses on the MDQ were compared to responses gathered in a structured patient-physician interview. A separate group of 70 outpatients completed the MDQ twice to assess the reproducibility of each item. A total of 148 patients participated in the validation process (78 [53%] men; mean age 62). On average, the MDQ took 6 minutes to complete. A single item (odynophagia) tested poorly with a kappa value of < 0.4. Otherwise, the majority of concurrent validity kappa values were in the good to excellent range with a mean of 0.63 (95% CI 0.22,0.89). The majority of reproducibility kappa values were also in the good to excellent range with a median kappa value of 0.76 (interquartile range: 0.67,0.81). Cronbach's alpha values were excellent in the range of 0.86,0.88. Spearman rank correlation coefficients to assess construct validity were also excellent in the range of 0.87,0.98. Thus, the MDQ is a concise instrument that demonstrates overall excellent concurrent validity, reproducibility, internal consistency, and construct validity for the features of esophageal dysphagia. [source] Comprehensive validation of competencies for dental vocational training and general professional trainingEUROPEAN JOURNAL OF DENTAL EDUCATION, Issue 4 2003L. Prescott This paper outlines a study designed to validate competencies for dental vocational training (DVT) and general professional training (GPT) in order to ensure their accuracy and acceptability. A highly inclusive approach is described whereby all trainers in Scotland were invited to participate in the exercise. The 168 individuals recruited were drawn from all branches of the dental services and all regions in Scotland. Using online or paper questionnaires, quantitative and qualitative data were collected for each competency statement over 9 months, after which focus groups discussed and decided which changes should be made. A high response rate was observed and from the 160 competencies originally identified, almost half (47.5%) were redrafted as a direct result of the validation process. Sections of the competency document that required most attention are discussed, as are the nature of changes made to the competencies. As a result of this study, a fully validated competency document for DVT and GPT has been produced and will allow a high degree of standardization of training through the provision of essential consistent information to trainers and VDPs. [source] Modelling for an expert system and a parameter validation methodEXPERT SYSTEMS, Issue 5 2002A. Chatzinikolaou A model,based engineering diagnostic method is typically based on the evaluation of the residuals generated from a comparison of important variable values from a simulated system and the corresponding measured values from the system's performance. Consequently, a model should describe the dynamic behaviour of the system as accurately as possible using suitably selected parameter values. This implies the need for validation of the performance of the model by comparison with the measurements of the actual system. This process is especially important when the detection of faults is performed in real,time conditions. In this paper, the modelling process for hydraulic systems as well as a new parameter validation method that has been developed using the DASYLab data acquisition and control software for the estimation of the uncertain parameter values of the model is presented. This model validation process led to the establishment of a model,based expert system that is able to diagnose real,time faults working in parallel with actual dynamic industrial automated processes. [source] Estimating annual N2O emissions from agricultural soils in temperate climatesGLOBAL CHANGE BIOLOGY, Issue 10 2005Caroline Roelandt Abstract The Kyoto protocol requires countries to provide national inventories for a list of greenhouse gases including N2O. A standard methodology proposed by the Intergovernmental Panel on Climate Change (IPCC) estimates direct N2O emissions from soils as a constant fraction (1.25%) of the nitrogen input. This approach is insensitive to environmental variability. A more dynamic approach is needed to establish reliable N2O emission inventories and to propose efficient mitigation strategies. The objective of this paper is to develop a model that allows the spatial and temporal variation in environmental conditions to be taken into account in national inventories of direct N2O emissions. Observed annual N2O emission rates are used to establish statistical relationships between N2O emissions, seasonal climate and nitrogen-fertilization rate. Two empirical models, MCROPS and MGRASS, were developed for croplands and grasslands. Validated with an independent data set, MCROPS shows that spring temperature and summer precipitation explain 35% of the variance in annual N2O emissions from croplands. In MGRASS, nitrogen-fertilization rate and winter temperature explain 48% of the variance in annual N2O emissions from grasslands. Using long-term climate observations (1900,2000), the sensitivity of the models with climate variability is estimated by comparing the year-to-year prediction of the model to the precision obtained during the validation process. MCROPS is able to capture interannual variability of N2O emissions from croplands. However, grassland emissions show very small interannual variations, which are too small to be detectable by MGRASS. MCROPS and MGRASS improve the statistical reliability of direct N2O emissions compared with the IPCC default methodology. Furthermore, the models can be used to estimate the effects of interannual variation in climate, climate change on direct N2O emissions from soils at the regional scale. [source] Validation of Numerical Ground Water Models Used to Guide Decision MakingGROUND WATER, Issue 2 2004Ahmed E. Hassan Many sites of ground water contamination rely heavily on complex numerical models of flow and transport to develop closure plans. This complexity has created a need for tools and approaches that can build confidence in model predictions and provide evidence that these predictions are sufficient for decision making. Confidence building is a long-term, iterative process and the author believes that this process should be termed model validation. Model validation is a process, not an end result. That is, the process of model validation cannot ensure acceptable prediction or quality of the model. Rather, it provides an important safeguard against faulty models or inadequately developed and tested models. If model results become the basis for decision making, then the validation process provides evidence that the model is valid for making decisions (not necessarily a true representation of reality). Validation, verification, and confirmation are concepts associated with ground water numerical models that not only do not represent established and generally accepted practices, but there is not even widespread agreement on the meaning of the terms as applied to models. This paper presents a review of model validation studies that pertain to ground water flow and transport modeling. Definitions, literature debates, previously proposed validation strategies, and conferences and symposia that focused on subsurface model validation are reviewed and discussed. The review is general and focuses on site-specific, predictive ground water models used for making decisions regarding remediation activities and site closure. The aim is to provide a reasonable starting point for hydrogeologists facing model validation for ground water systems, thus saving a significant amount of time, effort, and cost. This review is also aimed at reviving the issue of model validation in the hydrogeologic community and stimulating the thinking of researchers and practitioners to develop practical and efficient tools for evaluating and refining ground water predictive models. [source] Factors affecting transfer of training in ThailandHUMAN RESOURCE DEVELOPMENT QUARTERLY, Issue 3 2005Siriporn Yamnill To begin the validation process for the Learning Transfer System Inventory (LTSI) in Thailand, research replicating Holton, Bates, and Ruona's study (2000) was conducted in Thailand. The LTSI was administered to 1,029 employees. Exploratory factor analysis and MANOVA were used to identify factors. A factor structure almost identical to that of Holton and colleagues was identified. Perceived content validity of the training was identified as the most important factor. Organization type created the greatest number of differences among variables tested. [source] Abstracts of the 8th Meeting of the Italian Peripheral Nerve Study Group: 46JOURNAL OF THE PERIPHERAL NERVOUS SYSTEM, Issue 1 2003L Padua Traditional outcome assessment in neurological diseases has always been based on physician-derived and instrumental findings. Over the last two decades, clinical and public health researchers emphasized the need for a thorough evaluation of concepts such as Health Related Quality of Life (HRQoL) to study the impact of chronic illnesses and their treatments on the patient's life. The most frequent inherited neuropathy is Charcot-Marie-Tooth disease (CMT). CMT Patients develop progressive weakness and sensory disturbances, becoming sometimes severely disabled even at very young age. In CMT clinic, neurophysiologic, pathologic and genetic evaluation, are considered fundamental to assess nerve involvement and diagnose, but how these findings are related to HRQoL and disability is not assessed. We propose a prospective follow-up (24,30 months) of CMT patients with multiple measurements of CMT. Besides conventional clinic, pathologic, neurophysiologic and genetic measurements we adopt validated patient-oriented measurements to assess HRQoL and disability. Aims of the study are: 1) to assess HRQoL and disability of CMT patients in a wide and well-represented sample and to evaluate the relationships between conventional parameters and the patient's perception of his own HRQoL and disability; 2) to evaluate natural history of HRQoL and disability in CMT, and to evaluate the predictive value of phenotype, genetic picture, neurophysiological and pathological pattern 3) to develop a national network and a database on CMT disease (this aim includes the standardization, based on a consensus validation process, of the most used terms and measurements in CMT and the development of a database software). In a preliminary reunion, the authors developed a dedicated database for patients affected by CMT. Details about this database will be presented. [source] Neue Methoden zur Beurteilung der Betriebsfestigkeit im Fahrzeugauslegungs- und -absicherungsprozessMATERIALWISSENSCHAFT UND WERKSTOFFTECHNIK, Issue 10 2008M. Brune Fatigue strength; design and validation process; method development; load data simulation; lightweight design; short fibre reinforced polymers; material porosity; die casted aluminium Abstract Der moderne Auslegungs- und Absicherungsprozess in der Automobilindustrie beinhaltet experimentelle, messtechnische und auch rechnerische Methoden. Dieser Beitrag erläutert anhand von Beispielen neue Entwicklungen in der Betriebsfestigkeitsauslegung, insbesondere auf dem Gebiet der virtuellen Methoden. Dies bezieht sich zum einen auf die virtuelle Lastdatenermittlung, zum anderen auf die Verbesserung der rechnerischen Lebensdauerabschätzung. Hier werden zwei aktuelle Beispiele der Methodenentwicklung erläutert. Das erste Beispiel behandelt die Berücksichtigung von Werkstoffinhomogenitäten bei der Berechnung von Aluminium-Gussbauteilen, das zweite Beispiel beschreibt die Vorgehensweise der Auslegung von Bauteilen aus kurzfaserverstärkten Kunststoffen mittels eines neuen Berechnungsverfahrens. Advanced durability evaluation in vehicle design and validation process The modern process of evaluation and validation conducted in the automotive industry uses experimental, metrological, and calculation-based methods. Offering various examples, the present paper describes new developments in the determination and evaluation of operating strength, particularly in terms of virtual methods and their application in practice. The first point considered is the virtual determination of load data, the second is the improvement of calculated fatigue life. Two current examples in the development of methods are presented in this context: The first example examines the inhomogeneity of materials in calculating aluminium castings. The second example describes the approach taken in the configuration of components made of short-fibre-reinforced polymers, applying a new method of calculation. [source] Initial testing of topotecan by the pediatric preclinical testing program,PEDIATRIC BLOOD & CANCER, Issue 5 2010Hernan Carol PhD Abstract Background Topotecan is a small molecule DNA topoisomerase I poison, that has been successful in clinical trials against pediatric solid tumors and leukemias. Topotecan was evaluated against the Pediatric Preclinical Testing Program (PPTP) tumor panels as part of a validation process for these preclinical models. Procedures In vivo three measures of antitumor activity were used: (1) an objective response measure modeled after the clinical setting; (2) a treated to control (T/C) tumor volume measure; and (3) a time to event (fourfold increase in tumor volume for solid tumor models, or ,25% human CD45+ cells in the peripheral blood for acute lymphoblastic leukemia, ALL models) measure based on the median event-free survival (EFS) of treated and control animals for each xenograft. Results Topotecan inhibited cell growth in vitro with IC50 values between 0.71 and 489,nM. Topotecan significantly increased EFS in 32 of 37 (87%) solid tumor xenografts and in all 8 of the ALL xenografts. Seventy-five percent of solid tumors met EFS T/C activity criteria for intermediate (n,=,17) or high activity (n,=,7). Objective responses were noted in eight solid tumor xenografts (Wilms, rhabdomyosarcoma, Ewing sarcoma, neuroblastoma). Among the six neuroblastomas, three achieved a PR. For the ALL panel, two maintained CRs, three CRs, and two PRs were observed. Conclusions Topotecan demonstrated broad activity in vitro and in vivo against both the solid tumor and ALL panels, with significant tumor growth delay generated in all the panels. These results further demonstrate the validity of the PPTP panel for preclinical testing of new drugs. Pediatr Blood Cancer 2010;54:707,715. © 2009 Wiley-Liss, Inc. [source] Profiling of vitreous proteomes from proliferative diabetic retinopathy and nondiabetic patientsPROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 22 2007Taeoh Kim Abstract Diabetes can lead to serious microvascular complications like proliferative diabetic retinopathy (PDR), which is the leading cause of blindness in adults. The proteomic changes that occur during PDR cannot be measured in the human retina for ethical reasons, but could be reflected by proteomic changes in vitreous humor. Thus, we considered that comparisons between the proteome profiles of the vitreous humors of PDR and nondiabetic controls could lead to the discovery of novel pathogenic proteins and clinical biomarkers. In this study, the authors used several proteomic methods to comprehensively examine vitreous humor proteomes of PDR patients and nondiabetic controls. These methods included immunoaffinity subtraction (IS)/2-DE/MALDI-MS, nano-LC-MALDI-MS/MS, and nano-LC-ESI-MS/MS. The identified proteins were subjected to the Trans-Proteomic Pipeline validation process. Resultantly, 531 proteins were identified, i.e., 415 and 346 proteins were identified in PDR and nondiabetic control vitreous humor samples, respectively, and of these 531 proteins, 240 were identified for the first time in this study. The PDR vitreous proteome was also found to contain many proteins possibly involved in the pathogenesis of PDR. The proteins described provide the most comprehensive proteome listing in the vitreous humor samples of PDR and nondiabetic control patients. [source] Validation of commercial computerised systems using a single life cycle document (integrated validation document)QUALITY ASSURANCE JOURNAL, Issue 2 2009R. D. McDowall Abstract A risk-based approach to the validation of low risk commercially available computerised systems is described. To determine if validation is required, the business process automated by the system is assessed to see if it is regulated. If validation is required, then the Good Automated Manufacturing Practice (GAMP) software category is mapped against the impact of the records generated by the system to determine if full or reduced validation is required. If reduced validation is indicated, the use of a single integrated validation document is proposed and illustrated with two case study examples. The use of a Validation Master Plan (VMP) to facilitate this validation process is also presented and described. Copyright © 2009 John Wiley & Sons, Ltd. [source] Quality of life in allergic rhinitisCLINICAL & EXPERIMENTAL ALLERGY REVIEWS, Issue 3 2006G. Passalacqua Summary Quality of life (QoL)or, better, health-related quality of life, is now recognized as a crucial aspect in assessing the impact of a given disease on the general well-being of patients. This fact was ascertained in the last 10 years also for respiratory allergy (asthma and rhinitis). In particular, it was shown that allergic rhinitis (AR), although not life threatening, profoundly affects many aspects of everyday life. In this regard, a number of specific questionnaires (instruments) have been developed and validated to assess the quality of life in adults, adolescents and children. Although the concept of QoL is easy to understand, the development and validation process of questionnaires is quite complex and time consuming. The literature provided strong evidence of the effects of AR and its treatments on QoL, but also evidenced some controversial points, including the weak correlation of QoL with objective parameters. It has therefore become clear that QoL questionnaires measure aspects of the disease that partially differ from the routinely evaluated parameters and that quality of life should integrate, not replace, the objective measurements. In the near future, ,sharper' instruments are expected to be developed for the evaluation of quality of life and of the effects of treatments in AR. [source] Cognitive impairment in Parkinson's disease: Tools for diagnosis and assessment,,MOVEMENT DISORDERS, Issue 8 2009Jaime Kulisevsky MD Abstract Cognitive impairment (CI) and dementia are frequent and debilitating features associated with Parkinson's disease (PD). Formal neuropsychological examination is required to ascertain the degree and pattern of CI over the course of the disease. The use of different tools may explain heterogeneous data obtained from studies to date. Normative data for extensively used scales [Mattis Dementia Rating Scale (MDRS), Mini-Mental State Examination (MMSE)] is incomplete in PD populations. According to sample characteristics, statistical analyses, and methodological quality, 33 studies using scales not specific to PD (MDRS, MMSE, Cambridge Cognitive Assessment, FAB) or PD-specific scales (Mini-Mental Parkinson, Scales for Outcomes of Parkinson's disease,Cognition, Parkinson's Disease,Cognitive Rating Scale, and Parkinson Neuropsychometric Dementia Assessment) were eligible for the critical analysis of their appropriateness to assess cognition in PD. Of the four scales specifically designed for PD, the SCOPA-COG and the PD-CRS have undergone extensive and rigorous validation processes. While the SCOPA-COG mainly assesses "frontal-subcortical" cognitive defects, the PD-CRS also assesses "instrumental-cortical" functions, allowing better characterization of the different patterns of CI that may be present in PD from the earliest stages. The MMP and PANDA scales were designed as brief screening tests for CI and have not yet been subjected to extensive clinimetric evaluations. Further research on PD-specific tools seems mandatory to help establish accurate cut-off scores for the diagnosis of mild PDD, detect cognitive profiles more prone to the future development of dementia, and allow comparisons between different descriptive or interventional studies. © 2009 Movement Disorder Society [source] ORIGINAL RESEARCH,PAIN: Vaginismus and Dyspareunia: Automatic vs.THE JOURNAL OF SEXUAL MEDICINE, Issue 6 2010Deliberate Disgust Responsivity ABSTRACT Introduction., The difficulty of penetration experienced in vaginismus and dyspareunia may at least partly be due to a disgust-induced defensive response. Aims., To examine if sex stimuli specifically elicit: (i) automatic disgust-related memory associations; (ii) physiological disgust responsivity; and/or (iii) deliberate expression of disgust/threat. Methods., Two single target Implicit Association Task (st-IAT) and electromyography (EMG) were conducted on three groups: vaginismus (N = 24), dyspareunia (N = 24), and control (N = 31) group. Main Outcome Measures., st-IAT, to index their initial disgust-related associations and facial EMG for the m. levator labii and m. corrugator supercilii regions. Results., Both clinical groups showed enhanced automatic sex-disgust associations. As a unique physiological expression of disgust, the levator activity was specifically enhanced for the vaginismus group, when exposed to a women-friendly SEX video clip. Also at the deliberate level, specifically the vaginismus group showed enhanced subjective disgust toward SEX pictures and the SEX clip, along with higher threat responses. Conclusions., Supporting the view that disgust is involved in vaginismus and dyspareunia, for both, clinical groups' sex stimuli automatically elicited associations with disgust. Particularly for the vaginismus group, these initial disgust associations persisted during subsequent validation processes and were also evident at the level of facial expression and self-report data. Findings are consistent with the notion that uncontrollable activated associations are involved in eliciting defensive reactions at the prospect of penetration seen in both conditions. Whereas deliberate attitudes, usually linked with the desire for having intercourse, possibly generate the distinction (e.g., severity) between these two conditions. Borg C, de Jong PJ, and Schultz WW. Vaginismus and dyspareunia: Automatic vs. deliberate disgust responsivity. J Sex Med 2010;7:2149,2157. [source] | |||||||||||||||||||||||||