Anne Collard

Reasoning versus knowledge retention and ascertainment throughout a problem-based learning curriculum.

Context  Since 2000, problem‐based learning (PBL) seminars have been introduced into the curriculum of medical studies at the University of Liège. We aimed to carry out a cross‐sectional investigation of the maturational increase in biomedical reasoning capacity in comparison with factual knowledge retention throughout the curriculum.

Rank-preserving geometric means of positive semi-definite matrices

Abstract The generalization of the geometric mean of positive scalars to positive definite matrices has attracted considerable attention since the seminal work of Ando. The paper generalizes this framework of matrix means by proposing the definition of a rank-preserving mean for two or an arbitrary number of positive semi-definite matrices of fixed rank. The proposed mean is shown to be geometric in that it satisfies all the expected properties of a rank-preserving geometric mean. The work is motivated by operations on low-rank approximations of positive definite matrices in high-dimensional spaces.

Anisotropy Preserving DTI Processing

Statistical analysis of diffusion tensor imaging (DTI) data requires a computational framework that is both numerically tractable (to account for the high dimensional nature of the data) and geometric (to account for the nonlinear nature of diffusion tensors). Building upon earlier studies exploiting a Riemannian framework to address these challenges, the present paper proposes a novel metric and an accompanying computational framework for DTI data processing. The proposed approach grounds the signal processing operations in interpolating curves. Well-chosen interpolating curves are shown to provide a computational framework that is at the same time tractable and information relevant for DTI processing. In addition, and in contrast to earlier methods, it provides an interpolation method which preserves anisotropy, a central information carried by diffusion tensor data.

Longitudinal assessment of progress in reasoning capacity and relation with self-estimation of knowledge base

The aim of the study was to investigate progress in reasoning capacity and knowledge base appraisal in a longitudinal analysis of data from summative evaluation throughout a medical problem-based learning curriculum. The scores in multidisciplinary discussion of a clinical case and multiple choice questionnaires (MCQs) were studied longitudinally for 213 students from years 2 to 5. The capacity of core knowledge delimitation was calculated as the difference between the levels of average ascertainment degrees given for correct and incorrect answers at MCQ. For both multidisciplinary discussion of a clinical case evaluation and self-estimation of core knowledge, the capacity increases throughout the curriculum. The reasoning capacity assessed through multidisciplinary discussion of a clinical case is positively correlated with MCQ scores and the capacity to discriminate the mastered core knowledge. In conclusion, this study indicates that self-estimation of core knowledge is associated with an increase in reasoning performance through a well-organised knowledge base. Since that ability is related to success or failure, it is suggested that student awareness about delimitation of mastered core knowledge is considered as part of learning.

Statistical tests for group comparison of manifold-valued data

Motivated by population studies of Diffusion Tensor Imaging, the paper investigates the use of mean-based and dispersion-based permutation tests to define and compute the significance of a statistical test for data taking values on nonlinear manifolds. The paper proposes statistical tests that are computationally tractable and geometrically sound for Diffusion Tensor Imaging.

Context impact of clinical scenario on knowledge transfer and reasoning capacity in a medical problem-based learning curriculum

ABSTRACT Since 2000, the faculty of Medicine at the University of Liège has integrated problem-based learning (PBL) seminars from year two to seven in its seven-year curriculum. The PBL approach has been developed to facilitate students’ acquisition of reasoning capacity. This contextualized learning raises the question of the de- and re-contextualization process and its development during medical education. The aim is to assess transfer capacity of knowledge acquired through contextualized learning. A script concordance test (SCT) to assess clinical reasoning was administered to 104 volunteer students from year three to six of the Faculty of Medicine, and to a reference panel. The SCT has been created to measure, in a standardized way, reasoning capacity for ill-defined clinical problems. We used clinical cases from PBL seminars related to endocrinology from the third- and fifth-year (APP [Apprentissage Par Problèmes] and ARC [Apprentissage du Raisonnement Clinique] seminars). Two SCT scenarios aiming at the same learning objectives were created: one in the original learning context and one in a different, new context. Irrespective of the learning context, the reference panel showed higher scores than all groups of students. Students in year five and six obtained higher scores than younger students. A significant difference was also found in relation to the context (original/new) of the question. Higher scores were unexpectedly obtained for questions related to ARC cases than APP cases and in new contexts versus original ones, irrespective of the study level. The highest score was obtained for fifth-year cases in a new context. This study shows that from third year, students are able to transfer the knowledge acquired throughout PBL seminars for application to questions with information out of the learning context. Moreover, reasoning capacity grows with experience, irrespective of the process of transfer.