Integration of one- and two-dimensional motion signals in infants: evidence from the barber-pole illusion

Several previous studies in adults have investigated how one- and two-dimensional moving features are integrated into a coherent global motion percept by studying the "barber-pole illusion"; when a one-dimensional moving grating is presented within a rectangular aperture, the two-dimensional line terminators at the edges of the aperture bias the perceived direction of motion toward the longer axis of the aperture. In the current study, we used barber-pole stimuli to investigate the development of motion mechanisms that integrate one- and two-dimensional motion signals. Using a directional eye movement technique, we measured responses to obliquely moving gratings presented within horizontally vs. vertically oriented apertures, in infants (ages 2-5 months) and adults. For all ages, we found that horizontal eye movements were significantly stronger when gratings were presented within horizontal than within vertical apertures, as predicted by the barber-pole illusion. Additionally, we devised a way to infer the "effective shift" in eye movement direction produced by the barber-pole illusion. Using a simple motion integration model, effective shift values were then used to calculate the relative weightings of one- and two-dimensional motion signals to direction coding. The results show that by 2 months of age, infants integrate one- and two-dimensional motion signals, and that the relative weighting of one- and two-dimensional signals remains roughly constant from 2 months of age into adulthood.     

Post-migration geographical mobility, mental health and health service utilisation among Somali refugees in the UK: a qualitative study

Migration is known to be associated with poor health outcomes for certain marginalised and socially disadvantaged populations. This paper reviews a number of reasons why residential mobility in the 'host' country may be associated with poor mental health for refugee populations and reports on a qualitative study of Somalis living in London, UK, and their beliefs about the relationship between residential mobility, poor health and health service use. Two discussion groups were undertaken with 13 Somali professionals and four groups with 21 lay Somalis in East and South London, UK. Lay Somalis did not wish to move accommodation but felt they were forced to move. Some Somali professionals believed that the nomadic history of Somalis made them more likely to elect to move in order to escape problems of living, but this was not supported by the lay group. Frequent geographical movements were seen as stressful and undesirable, disrupted family life and child development and were detrimental to well being. Residential mobility was also perceived to interfere with health care receipt and therefore should be more comprehensively assessed in larger quantitative studies.     

Differential Effects of Two Types of Formative Assessment in Predicting Performance of First-year Medical Students

Formative assessments are systematically designed instructional interventions to assess and provide feedback on students’ strengths and weaknesses in the course of teaching and learning. Despite their known benefits to student attitudes and learning, medical school curricula have been slow to integrate such assessments into the curriculum. This study investigates how performance on two different modes of formative assessment relate to each other and to performance on summative assessments in an integrated, medical-school environment. Two types of formative assessment were administered to 146 first-year medical students each week over 8 weeks: a timed, closed-book component to assess factual recall and image recognition, and an un-timed, open-book component to assess higher order reasoning including the ability to identify and access appropriate resources and to integrate and apply knowledge. Analogous summative assessments were administered in the ninth week. Models relating formative and summative assessment performance were tested using Structural Equation Modeling. Two latent variables underlying achievement on formative and summative assessments could be identified; a “formative-assessment factor” and a “summative-assessment factor,” with the former predicting the latter. A latent variable underlying achievement on open-book formative assessments was highly predictive of achievement on both open- and closed-book summative assessments, whereas a latent variable underlying closed-book assessments only predicted performance on the closed-book summative assessment. Formative assessments can be used as effective predictive tools of summative performance in medical school. Open-book, un-timed assessments of higher order processes appeared to be better predictors of overall summative performance than closed-book, timed assessments of factual recall and image recognition. This research was presented at the 86th Annual Meeting of the American Educational Research Association (AERA) in Montreal, Canada, April 11–15, 2005.     

Teaching and evaluating first and second year medical students' practice of evidence-based medicine

PURPOSE: To implement an evidence-based medicine (EBM) curriculum for Year 1 and 2 medical students, and to develop a method to evaluate their practice of EBM in discrete and relevant worksteps. METHODS: For the 100 students entering Year 1 of their medical education in 2000, we implemented a curriculum with 25-30 student contact hours of EBM instruction which used a variety of teaching formats and spanned the first and second years of their training. We developed an evaluation module that assessed the following 5 steps in the practice of EBM: generating well built questions; searching for evidence; critical appraisal; applying the evidence, and self-evaluation. We tested 2 different versions of the test module 3-months apart with the same cohort of second year students, and correlated their scores on the second module with examination components of a comprehensive assessment. We obtained feedback from the students regarding the EBM curriculum and evaluation method. RESULTS: Each test module took 2-4 hours to complete and 5-8 minutes to grade. There was moderate test-retest reliability for the total test scores (r = 0.35, P < 0.001). Step 1 scores correlated with the mock board examination scores (r = 0.23, P = 0.05). Step 2 scores correlated with the peer assessment factor "work habits" (r = 0.24, P = 0.02), and Step 3 scores correlated with clinical reasoning exercises (r = 0.31, P = 0.002). Step 4 scores lacked test-retest reliability and did not correlate with components of the comprehensive assessment. The majority of students felt there was too much focus on EBM during the first 2 years of the curriculum and they rated the EBM test module the lowest rated component of the comprehensive assessment. CONCLUSIONS: Although we have demonstrated preliminary reliability and validity of a new evaluation instrument that assess the domains of scientific knowledge, work habits and reasoning skills required in the practice of EBM, many of the correlations were weak, and we remain in the very early stages of determining if, when and how EBM instruction should occur in medical education.     

Learning management systems: technology to measure the medical knowledge competency of the ACGME

AIMS: We report how the learning management system (LMS) Web Course Tools (WebCT) was used to design, implement and evaluate the web-based course "Principles of Ambulatory Paediatrics", taken by paediatric residents during an ambulatory block rotation. This report also illustrates how WebCT can be used to measure the medical knowledge competency required by the Accreditation Council for Graduate Medical Education (ACGME). METHODS: Eighty paediatric residents completed a 1-month outpatient rotation between July 1, 2001 and June 30, 2002. During this rotation residents were required to complete 4 modules in asthma, otitis media, gastroenteritis and fever, respectively. Each module was evaluated using a standard questionnaire. RESULTS: Completion rates for the required modules ranged from 64-72%. Residents in all 3 years of training showed improvement between the pre- and post-test scores for each module, except for postgraduate Year 2 residents in the asthma module. Most residents somewhat agreed, agreed or strongly agreed that the module components were useful and that the experience of completing the modules would improve their ability to take care of patients. CONCLUSIONS: The LMS WebCT is an innovative and adaptable approach for designing a web-based course for primary care education in paediatrics. The LMS addresses the educational needs of both a clinical division and a residency programme. The LMS also provides an information technology infrastructure to measure the medical knowledge competency required by the ACGME.     

A randomised trial of an online lecture with and without audio

Objective  To determine the impact of adding audio-feed to an online lecture on screening given to medical students who were participating in an outpatient clerkship.
Design  Prospective, randomised, controlled study.
Setting  Vanderbilt University School of Medicine, Nashville and Wake Forest Medical School, Winston-Salem.
Participants  A total of 59 Years 3 and 4 medical students.
Main outcome measures  Students' use of time, satisfaction with the lecture experience, and knowledge.
Educational intervention  The online lecture was developed at Vanderbilt University. At Vanderbilt, 16 Year 4 medical students were randomised to the lecture on screening with audio and 17 Year 4 medical students were randomised to the same lecture without audio. At Wake Forest, 13 Year 3 medical students were randomised to the lecture on screening with audio and 13 Year 3 students were randomised to the same lecture without audio.
Results  The audio lecture required 20 more minutes to complete than the non-audio lecture. Students in the audio group were more satisfied with their experience than students in the non-audio group. Students in the audio-feed group achieved a trend for higher post-intervention knowledge scores, with the difference attributed to the students at Vanderbilt.
Conclusion  Audio narration is an important aspect of an online lecture. The distribution of online lectures to students at different sites and different training levels requires further study.     

Gender as a variable in the assessment of final year degree-level communication skills

AIM: To investigate possible bias due to gender combination of students, role players and examiners in a high-stakes assessment. SETTING: Valid oral interactive contextualized examinations (VOICEs) is a long-station OSCE-style exam in general practice (GP). At the time of writing it consisted of 65% of the student's final GP mark. METHOD: In the VOICE, students undertake six tasks--four vivas and two role-plays. "Patient" roles are taken by professional role players who work regularly on the undergraduate curriculum. During the role-play, the student's clinical competence is assessed by an observing GP examiner. The communication skills marks are awarded by the role player and the examiner together, by negotiation. Data have been recorded detailing the role player's initial marks, the examiner's initial marks and their final (awarded) agreed marks for 1024 consultations. SAMPLE: 512 final year medical students, 28 role players and 48 examiners. There were no inclusion or exclusion criteria. All those present on exam day became part of the data. RESULTS: There was a significant relationship between gender and performance for some, but not all, stations. Correlations for multiple comparisons removed the significance. Female students perform better across the board than male students. While not always significant, this did affect grading. There was no significant association between the genders of role players and examiners with the question choices. There has been a significant worsening of male results since 1999. Differences exist in the way that pairs of mixed or single genders score students.     

Social and behavioural science education in UK medical schools: current practice and future directions

INTRODUCTION: The increasing importance accorded the social and behavioural sciences in medical education presents opportunities for developing new and innovative forms of teaching and learning in this field. Yet social and behavioural scientists often feel isolated and marginalized. This research was designed to build a network of such practitioners to share and compare current practice, and to develop better models and resources. METHODS: Questionnaire survey and workshop discussions describe current practice among social and behavioural scientists in UK medical education, and identify current and future issues. RESULTS: Most UK medical curricula feature a significant social and behavioural science component, often in multidisciplinary contexts. Questions of core content, and how this relates to desired learning outcomes, particularly in the attitudinal sphere, remain unresolved. Identity problems result from differing perspectives of medics and social and behavioural scientists, staffing constraints, assessment regimes, and relationships with external examiners. DISCUSSION: This project identified barriers and opportunities for providing adequate training in the social and behavioural sciences in medical schools. Some of the barriers are common to higher education generally. Through our network, a database of core cases and assessments can be developed that would be available to all for teaching purposes. CONCLUSION: Social and behavioural scientists involved in medical education show commonality and difference in the extent and scope of their input. While they have made great progress, there remains much to achieve.     

Crisis resource management training for an anaesthesia faculty: a new approach to continuing education

BACKGROUND: Human error and system failures continue to play a substantial role in adverse outcomes in health care. Anaesthesia crisis resource management addresses many patient safety issues by teaching behavioural skills for critical events but it has not been systematically utilized to teach experienced faculty. METHODS: An anaesthesia crisis resource management course was created for the faculty of our medical school's anaesthesia teaching programmes. The course objectives were to understand and improve participants' proficiency in crisis resource management (CRM) skills and to learn skills for debriefing residents after critical events. Through surveys, measurement objectives assessed acceptance, utility and need for recurrent training immediately post-course. These were measured again approximately 1 year later along with self-perceived changes in the management of difficult or critical events. RESULTS: The highly rated course was well received in terms of overall course quality, realism, debriefings and didactic presentation. Course usefulness, CRM principles, debriefing skills and communication were highly rated immediately post-course and 1 year later. Approximately half of the faculty staff reported a difficult or critical event following the course; of nine self-reported CRM performance criteria surveyed all claimed improvement in their CRM non-technical skills. CONCLUSIONS: A unique and highly rated anaesthesia faculty course was created; participation made the faculty staff eligible for malpractice premium reductions. Self-reported CRM behaviours in participants' most significant difficult or critical events indicated an improvement in performance. These data provide indirect evidence supporting the contention that this type of training should be more widely promoted, although more definitive measures of improved outcomes are needed.     

Radiological and histological analysis of cortical allografts: an experimental study in sheep femora

Introduction We developed an experimental model in sheep femora to evaluate the process of cortical allograft incorporation.Materials and methods Twenty-four sheep were divided into four groups according to the various treatments of cortical allografts as follows: fresh, frozen, autoclaved, and frozen with perforation. Periodical radiographic and histological evaluations were performed for each group.Results Perforated frozen allograft proved to be superior radiographically in the first stage to fresh, frozen, and autoclaved forms. Revascularization was demonstrated by both Spalteholzs technique and histological examination. Histological analysis also showed creeping substitution, from the host bone to the allograft, which increased the reabsorption to facilitate new bone penetration, including endochondral ossification at the host-graft interface.Conclusion We believe that endochondral ossification is probably a biological event occurring routinely during the bone healing process and that the processes of incorporation of variously treated cortical allografts differ only at the early phase of implantation.