Diagnostic Models (diagnostic + models)

Distribution by Scientific Domains


Selected Abstracts


Algorithms for vector field generation in mass consistent models

NUMERICAL METHODS FOR PARTIAL DIFFERENTIAL EQUATIONS, Issue 4 2010
Ciro Flores
Abstract Diagnostic models in meteorology are based on the fulfillment of some time independent physical constraints as, for instance, mass conservation. A successful method to generate an adjusted wind field, based on mass conservation equation, was proposed by Sasaki and leads to the solution of an elliptic problem for the multiplier. Here we study the problem of generating an adjusted wind field from given horizontal initial velocity data, by two ways. The first one is based on orthogonal projection in Hilbert spaces and leads to the same elliptic problem but with natural boundary conditions for the multiplier. We derive from this approach the so called E,algorithm. An innovative alternative proposal is obtained from a second approach where we consider the saddle,point formulation of the problem,avoiding boundary conditions for the multiplier, and solving this problem by iterative conjugate gradient methods. This leads to an algorithm that we call the CG,algorithm, which is inspired from Glowinsk's approach to solve Stokes,like problems in computational fluid dynamics. Finally, the introduction of new boundary conditions for the multiplier in the elliptic problem generates better adjusted fields than those obtained with the original boundary conditions. © 2009 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 2010 [source]


Triage Patients with Suspected Pulmonary Embolism in the Emergency Department Using a Portable Ultrasound Device

ECHOCARDIOGRAPHY, Issue 5 2008
Nicolas Mansencal M.D.
The diagnosis of pulmonary embolism (PE) is difficult, despite validated diagnostic models. We sought to determine the value of a portable ultrasound device for triage of patients with suspected PE referred to the emergency department, using simplified echo criteria. We prospectively studied 103 consecutive patients with suspected PE, referred to our emergency department. After D-dimer screening, 76 patients were prospectively enrolled in this ultrasound study and underwent helical chest tomography, transthoracic echocardiography, and venous ultrasonography. Among patients with PE (n = 31), a right ventricular dilation was detected in 17 patients (55%), a direct visualization of clot in the lower limbs was present in 18 patients (58%), and 8 patients (26%) had both right ventricular dilation and deep venous thrombosis. The sensitivity and specificity of a combined ultrasound strategy using echocardiography and venous ultrasonography were respectively 87% (95% confidence interval 74% to 96%), and 69% (95% confidence interval 53% to 82%). The sensitivity of this combined strategy was significantly improved as compared to venous ultrasonography alone (P = 0.01) or echocardiography alone (P = 0.005). In patients with dyspnea or with high clinical probability of PE, this combined strategy was particularly relevant with high sensitivities (respectively 94% and 100%). Echocardiography combined with venous ultrasonography using a portable ultrasound device is a reliable method for screening patients with suspected PE referred to an emergency department, especially in patients with dyspnea or with high clinical probability. [source]


Association of coronary heart disease with age-adjusted aortocoronary calcification in patients with familial hypercholesterolaemia

JOURNAL OF INTERNAL MEDICINE, Issue 4 2000
J. M. Jensen
Abstract. Jensen JM, Gerdes LU, Jensen HK, Christiansen TM, Brorholt-Petersen JU, Faergeman O (Aarhus Amtssygehus University Hospital, Aarhus, Denmark). Association of coronary heart disease with age-adjusted aortocoronary calcification in patients with familial hypercholesterolaemia. J Intern Med 2000; 247: 479,484. Objectives. Existing algorithms of risk of coronary heart disease (CHD) do not pertain to patients with familial hypercholesterolaemia (FH), whose arteries have been exposed to hypercholesterolaemia since birth. We studied a cohort of FH patients to compare four diagnostic models of CHD: traditional risk factors of CHD (age, sex, cholesterol, hypertension, smoking and body mass index), cholesterol year score, and aortic as well as coronary calcium measured by spiral computed tomography (CT). Subjects. We invited 88 individuals with molecularly defined FH of whom 80 (91%) decided to participate. Results. Analysis of receiver operating characteristic curves showed that the age-adjusted coronary calcium score was more strongly associated with clinical manifestations of CHD than were traditional risk factors (P < 0.002), cholesterol year score (P << 0.0001), and the age-adjusted aortic calcium score (P < 0.0004). Conclusions. Age-adjusted coronary calcium score shows promise as an indicator of CHD in FH patients. [source]


Comparison of ecological validity of learning disabilities diagnostic models

PSYCHOLOGY IN THE SCHOOLS, Issue 2 2006
Vincent J. Dean
The purpose of this article is to examine models designed for the determination of a learning disability and compare them to specific criteria to determine whether the given diagnostic process is ecological in nature. The traditional child-centered deficit model (CCD), Relative Achievement Discrepancy model (RAD), and Responsiveness to Intervention model (RTI) were evaluated against the following three questions: (a) Does the environmental context of the assessment adequately represent the real-life situation? (b) Are the assessment stimuli relevant to the daily classroom activity? (c) Are the student behavior and/or required response natural and representative of the construct being assessed? The results of this examination suggested that the RTI has the most potential for ecological validity, but currently falls short. Suggestions for future research are included. © 2006 Wiley Periodicals, Inc. Psychol Schs 43: 157,168, 2006. [source]