Search results for "Correlation"
showing 10 items of 2282 documents
Neuroimaging correlates of insight in non-affective psychosis: A systematic review and meta-analysis.
2022
Abstract Objective Neurological correlates of impaired insight in non-affective psychosis remain unclear. This study aimed to review and meta-analyze the studies assessing the grey matter volumetric correlates of impaired insight in non-affective psychosis. Methods This study consisted of a systematic review of 23 studies, and a meta-analysis with SDM-PSI of the 11 studies that were whole-brain and reported maps or peaks of correlation of studies investigating the grey matter volumetric correlates of insight assessments of non-affective psychosis, PubMed and OVID datasets were independently reviewed for articles reporting neuroimaging correlates of insight in non-affective psychosis. Qualit…
Calculus Self-Efficacy Inventory : Its Development and Relationship with Approaches to Learning
2019
This study was framed within a quantitative research methodology to develop a concise measure of calculus self-efficacy with high psychometric properties. A survey research design was adopted in which 234 engineering and economics students rated their confidence in solving year-one calculus tasks on a 15-item inventory. The results of a series of exploratory factor analyses using minimum rank factor analysis for factor extraction, oblique promin rotation, and parallel analysis for retaining extracted factors revealed a one-factor solution of the model. The final 13-item inventory was unidimensional with all eigenvalues greater than 0.42, an average communality of 0.74, and a 62.55% variance…
Eficiencia en la educación superior. Estudio empírico en universidades públicas de Colombia y España
2020
Resumen En las últimas décadas, las universidades de Iberoamérica han introducido nuevos esquemas de evaluación de calidad y rendición de cuentas, inspirados en el modelo de la nueva gestión pública (NGP). En este contexto, la eficiencia en el reparto de los fondos públicos y la obtención del máximo rendimiento posible son una prioridad. Así, medir la eficiencia en el sector público, y específicamente en la educación superior, se ha convertido en un desafío para la ciencia contable. El objetivo de este trabajo es una propuesta para el cálculo de índices de eficiencia con modelos de análisis envolvente de datos (DEA), introduciendo un paso previo a través del análisis de correlación canónica…
Assessment of the reliability, validity, and responsiveness of a Spanish Asthma Quality of Life questionnaire.
1998
A Spanish-language questionnaire designed for measuring the impact of asthma on quality of life in adults was developed. It was derived, by the application of a rigorous translation protocol, from a previously validated, English-language Asthma Quality of Life (AQL) questionnaire which had been developed in Australia. The aim of this study was to evaluate the psychometric properties of the Spanish AQL questionnaire using a cross-sectional and longitudinal design. Two hundred ninety-four clinically stable subjects with asthma (168 women, mean baseline forced expiratory volume in 1 sec [FEV1] = 85% predicted), aged 17-70, attended for the initial baseline assessment. All subjects completed th…
Design and Simulation of Measurement-Based Correlation Models for Shadow Fading
2011
This paper deals with the design of measurement-based correlation models for shadow fading. Based on the correlation model, we design a simulation model using the sum-of-sinusoids (SOS) method to enable the simulation of spatial lognormal processes characterizing real-world shadow fading scenarios. The model parameters of the simulation model are computed by applying the Lp-norm method (LPNM). This method facilitates an excellent fitting of the simulation model’s autocorrelation function (ACF) to that of measured channels. Our study includes an evaluation of all important statistical quantities of the proposed measurement-based simulation model, such as the probability density function (PDF…
An Improved Iterative Nonlinear Least Square Approximation Method for the Design of SISO Wideband Mobile Radio Channel Simulators
2012
In this paper, we present an improved version of the iterative nonlinear least square approximation (INLSA) method for designing measurement-based single-input single-output (SISO) wideband channel simulators. The proposed method aims to fit the time-frequency correlation function (TFCF) of the simulation model to that of a measured channel. The parameters of the simulation model are determined iteratively by minimizing the Frobenius norm, which serves as a measure for the fitting error. In contrast to the original INLSA method, the proposed approach provides a unique optimized set of model parameters, which guarantees a quasi-perfect fitting with respect to the TFCF. We analyze the perform…
Comparison of histological and computed tomographic measurements of pig lung bronchi.
2020
Aim Light microscopy is used as template in the evaluation and further development of medical imaging methods. Tissue shrinkage caused by histological processing is known to influence lung tissue dimensions. In diagnosis of COPD, computed tomography (CT) is widely used for automated airway measurement. The aim of this study was to compare histological and computed tomographic measurements of pig lung bronchi. Methods Airway measurements of pig lungs were performed after freezing under controlled inflation pressure in a liquid nitrogen bath. The wall thickness of seven bronchi was measured via Micro-CT and CT using the integral-based method (IBM) and the full-width-at-half-maximum method (FW…
2021
Background MASK-air® is an app that supports allergic rhinitis patients in disease control. Users register daily allergy symptoms and their impact on activities using visual analog scales (VASs). We aimed to assess the concurrent validity, reliability, and responsiveness of these daily VASs. Methods Daily monitoring VAS data were assessed in MASK-air® users with allergic rhinitis. Concurrent validity was assessed by correlating daily VAS values with those of the EuroQol-5 Dimensions (EQ-5D) VAS, the Control of Allergic Rhinitis and Asthma Test (CARAT) score, and the Work Productivity and Activity Impairment Allergic Specific (WPAI-AS) Questionnaire (work and activity impairment scores). Int…
Effects of inhaled corticosteroids in stable chronic obstructive pulmonary disease.
2011
Chronic obstructive pulmonary disease (COPD) has been described as a heterogeneous multifactorial disorder associated with an abnormal inflammatory response of the peripheral airways and with variable morphologic, physiologic and clinical phenotypes. This notion of the disease is actually poorly supported by data, and there are substantial discrepancies and a weak correlation between inflammation, structural damage, functional impairment and degree of clinical symptoms. This problem is compounded by a poor understanding of the complexity and intricacies on the inflammatory pathways in COPD. Despite the evidence for efficacy of inhaled corticosteroids (ICS) on selected clinical endpoints in …
Calidad de vida en el asma: validación del cuestionario AQLQ para su utilización en población española
1995
The study of morbidity in asthma requires consideration not only of standard physiopathologic and function parameters, but also of the impact the disease has on the patient's life-style as he or she perceives it and evaluates it. The quantification of this factor, known as health-related quality of life (HRQL), is achieved by administering questionnaires specially designed for the purpose. We analyzed the reliability, content validity and construct validity (convergence and divergence) of one instrument, the Asthma Quality of Life Questionnaire (AQLQ) designed by Marks and colleagues. This questionnaire covers 4 dimensions (breathlessness, mood, social limitation and worrying) and gives a t…