Medical students' and tutors' experiences of directed and self-directed learning programs in evidence-based medicine: a qualitative evaluation accompanying a randomized controlled trial

This qualitative study aims to interpret the results of a randomized controlled trial comparing two educational programs (directed learning and self-directed learning) in evidence-based medicine (EBM) for medical students at the University of Oslo from 2002 to 2003. There is currently very little comparative educational research in this field. In the trial, no statistically significant differences between the study groups were shown for any outcomes considered (EBM knowledge, skills, and attitudes). Further analysis suggests that main reason for the negative trial results was that the majority of students learned equally effectively, whichever program they received, although implementation of the educational programs was not complete because of varying attendance. This study illustrates a stepwise evaluation model that might be useful in evaluating other socially complex interventions.     

Brain tumor-associated dementia

In this case study, we describe a patient with a dementia due to a brain tumor. This unusual cause of dementia illustrates the importance of a thorough evaluation of anyone who experiences relatively sudden changes in cognitive functions. The disorder had features common to other dementias but also had some unusual attributes that made a diagnosis of neurodegenerative disease less likely. Common features included intellectual decline involving difficulties in word-finding, the occurrence of paraphasia, poor concentration, disorientation in familiar environments, problems performing routine complex tasks, and elements of social withdrawal. Unlike more common degenerative dementias, however, there was no marked memory involvement. In addition, the onset of illness was rapid and associated with headaches, incontinence, and some gait and motor dysfunction.     

A case study in non-centering for data augmentation: Stochastic epidemics

In this paper, we introduce non-centered and partially non-centered MCMC algorithms for stochastic epidemic models. Centered algorithms previously considered in the literature perform adequately well for small data sets. However, due to the high dependence inherent in the models between the missing data and the parameters, the performance of the centered algorithms gets appreciably worse when larger data sets are considered. Therefore non-centered and partially non-centered algorithms are introduced and are shown to out perform the existing centered algorithms.     

Estimable Versions of Griffiths' Measure of Association

Many techniques have been proposed for measuring the degree of association between a pair of random variables X and Y. However, the measures often suffer from two drawbacks: they are difficult to calculate when the joint distribution of (X, Y) is known, and difficult to estimate when the joint distribution is unknown. In the present paper we present two modifications of a measure proposed by Griffiths (1972), and show that they exhibit neither of these deficiencies.     

Sibling resemblances in nonverbal skill and style

This study explored the hypothesis that siblings display a tendency for family resemblance in nonverbal decoding skills. Thirty-seven sibling pairs between the ages of 9 and 15 were administered the videotaped Nonverbal Discrepancy Test. This audiovisual test assesses (1) decoding accuracy—the extent to which subjects are able to identify affects (positivity and dominance) from face, body, and tone of voice cues; (2) discrepancy accuracy—the extent to which subjects recognize the degree of discrepancy between audio and video cues; and (3) video primacy—the extent to which subjects are more influenced by video (face or body) than by audio cues. Brother-brother pairs showed family resemblances in all three nonverbal indices, whereas brother-sister pairs displayed family similarity only in discrepancy accuracy. Overall, sibling pairs showed a tendency for family resemblance in nonverbal decoding. The processes that might lead siblings to develop similar patterns of nonverbal skills were discussed.