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Handover between colleagues is a complex task. The problem is that handovers are often inadequate because they are not structured according to theoretically grounded guidelines. Based on the cognitive load theory, we suggest that allowing a clarifying dialogue and thereby optimizing germane cognitive load enhances the information quality and diagnostic accuracy at handover, but may prolong handover duration. We also expect that mentioning key information first and thus decreasing intrinsic cognitive load improves information quality and diagnostic accuracy. We developed two representative paediatric cases for presentation in a factorial 2 × 2 design. Sixth-year medical students (N = 80) were randomly assigned to one of four groups that differed with regard to how the case histories were delivered to them (chronological order versus key information mentioned first) and direction of information exchange (unidirectional versus a clarifying dialogue). The receivers of the handover were asked to write a report of the cases and suggest the best diagnosis. Dependent variables were information quality of the written report (Information score), quality of the diagnosis (Diagnostic accuracy score) and the time it took to deliver the written handover case report (Handover report duration). Seen through the lens of cognitive load theory, allowing a clarifying dialogue at handover, and thus optimizing the germane cognitive load, significantly increased the Information score (p < 0.0005), Diagnostic accuracy score (< 0.05) and Handover report duration (p < 0.001).

Introduction: A new form of internationalization has been trending upward in the medical education realm: crossborder medical curriculum partnerships established to deliver the same, or adapted, curriculum to groups of geographically separated students. This study aims to investigate crossborder medical curriculum partnerships by exploring the experiences of teachers at the recipient institution who have a key role in delivering the program., Methods: From four pioneering recipient medical schools, 24 teachers participated in a Q-sort study. Each participant rank-ordered 42 statements about teaching in a crossborder medical curriculum on a scale from -5 (indicating strong disagreement) to +5 (indicating strong agreement). The authors conducted a "by-person" factor analysis to uncover distinct patterns in the ranking of statements, using the statistical results and participants' comments about their Q sorts to interpret these patterns and translate them into distinct viewpoints., Results: Three viewpoints emerged, reflecting: (1) a feeling of connectedness with the partner institution, trust in the quality of the curriculum, and appreciation of interinstitutional relationships; (2) the partnership's attractiveness because of the career opportunities it offers; and (3) concerns over the quality of graduates because of doubts about the appropriateness of the didactic model and insufficient attention to local healthcare needs, and over the practical feasibility of such partnerships., Conclusions: The three viewpoints identified revealed a pallet of views on how host teachers might experience their work. It shows the heterogeneous features of this group and seems to counterbalance reports that they are feeling "deprived" from their role as teacher. Two viewpoints featured an appreciation of interinstitutional relationships and of the partnership, especially when perceiving a degree of autonomy. Partners can capitalize on all different viewpoints by deploying procedure and policies to raise the quality of education delivery.

Background: Progress tests (PT) are used to assess students on topics from all medical disciplines. Progress testing is usually one of the assessment methods of the cognitive domain. There is limited knowledge on how positioning of the PT in a program of assessment (PoA) influences students' PT scores, use of PT feedback and perceived learning value., Methods: We compared PT total scores and use of a PT test feedback (ProF) system in two medical courses, where the PT is either used as a summative assessment or embedded in a comprehensive PoA and used formatively. In addition, an interview study was used to explore the students' perception on use of PT feedback and perceived learning value., Results: PT total scores were higher, with considerable effect sizes (ESs) and students made more use of ProF when the PT was embedded in a comprehensive PoA. Analysis of feedback in the portfolio stimulated students to look for patterns in PT results, link the PT to other assessment results, follow-up on learning objectives, and integrate the PT in their learning for the entire PoA., Conclusions: Embedding the PT in an assessment program designed according to the principles of programmatic assessment positively affects PT total scores, use of PT feedback, and perceived learning value.

Formula scoring (FS) is the use of a don't know option (DKO) with subtraction of points for wrong answers. Its effect on construct validity and reliability of progress test scores, is subject of discussion. Choosing a DKO may not only be affected by knowledge level, but also by risk taking tendency, and may thus introduce construct-irrelevant variance into the knowledge measurement. On the other hand, FS may result in more reliable test scores. To evaluate the impact of FS on construct validity and reliability of progress test scores, a progress test for radiology residents was divided into two tests of 100 parallel items (A and B). Each test had a FS and a number-right (NR) version, A-FS, B-FS, A-NR, and B-NR. Participants (337) were randomly divided into two groups. One group took test A-FS followed by B-NR, and the second group test B-FS followed by A-NR. Evidence for impaired construct validity was sought in a hierarchical regression analysis by investigating how much of the participants' FS-score variance was explained by the DKO-score, compared to the contribution of the knowledge level (NR-score), while controlling for Group, Gender, and Training length. Cronbach's alpha was used to estimate NR and FS-score reliability per year group. NR score was found to explain 27 % of the variance of FS [F(1,332) = 219.2, p < 0.0005], DKO-score, and the interaction of DKO and Gender were found to explain 8 % [F(2,330) = 41.5, p < 0.0005], and the interaction of DKO and NR 1.6 % [F(1,329) = 16.6, p < 0.0005], supporting our hypothesis that FS introduces construct-irrelevant variance into the knowledge measurement. However, NR-scores showed considerably lower reliabilities than FS-scores (mean year-test group Cronbach's alphas were 0.62 and 0.74, respectively). Decisions about FS with progress tests should be a careful trade-off between systematic and random measurement error.

Clinical clerks learn more than they are taught and not all they learn can be measured. As a result, curriculum leaders evaluate clinical educational environments. The quantitative Dundee Ready Environment Measure (DREEM) is a de facto standard for that purpose. Its 50 items and 5 subscales were developed by consensus. Reasoning that an instrument would perform best if it were underpinned by a clearly conceptualized link between environment and learning as well as psychometric evidence, we developed the mixed methods Manchester Clinical Placement Index (MCPI), eliminated redundant items, and published validity evidence for its 8 item and 2 subscale structure. Here, we set out to compare MCPI with DREEM. 104 students on full-time clinical placements completed both measures three times during a single academic year. There was good agreement and at least as good discrimination between placements with the smaller MCPI. Total MCPI scores and the mean score of its 5-item learning environment subscale allowed ten raters to distinguish between the quality of educational environments. Twenty raters were needed for the 3-item MCPI training subscale and the DREEM scale and its subscales. MCPI compares favourably with DREEM in that one-sixth the number of items perform at least as well psychometrically, it provides formative free text data, and it is founded on the widely shared assumption that communities of practice make good learning environments.

Morning reports offer opportunities for intensive work-based learning. In this controlled study, we measured learning processes and outcomes with the report of paediatric emergency room patients. Twelve specialists and 12 residents were randomised into four groups and discussed the same two paediatric cases. The groups differed in their presentation modality (verbal only vs. verbal + text) and the use of buzz groups (with vs. without). The verbal interactions were analysed for clinical reasoning processes. Perceptions of learning and judgment of learning were reported in a questionnaire. Diagnostic accuracy was assessed by a 20-item multiple-choice test. Combined bimodal presentation and buzz groups increased the odds ratio of clinical reasoning to occur in the discussion of cases by a factor of 1.90 (p = 0.013), indicating superior reasoning for buzz groups working with bimodal materials. For specialists, a positive effect of bimodal presentation was found on perceptions of learning (p < 0.05), and for residents, a positive effect of buzz groups was found on judgment of learning (p < 0.005). A positive effect of bimodal presentation on diagnostic accuracy was noted in the specialists (p < 0.05). Combined bimodal presentation and buzz group discussion of emergency cases improves clinicians' clinical reasoning and learning.

Background: The psychological construct of emotional intelligence (EI), its theoretical models, measurement instruments and applications have been the subject of several research studies in health professions education., Aim: The objective of the current study was to investigate the factorial validity and reliability of a bilingual version of the Schutte Self Report Emotional Intelligence Scale (SSREIS) in an undergraduate Arab medical student population., Methods: The study was conducted during April-May 2012. A cross-sectional survey design was employed. A sample (n = 467) was obtained from undergraduate medical students belonging to the male and female medical college of King Saud University, Riyadh, Saudi Arabia. Exploratory and confirmatory factor analysis was performed using SPSS 16.0 and AMOS 4.0 statistical software to determine the factor structure. Reliability was determined using Cronbach's alpha statistics., Results: The results obtained using an undergraduate Arab medical student sample supported a multidimensional; three factor structure of the SSREIS. The three factors are Optimism, Awareness-of-Emotions and Use-of-Emotions. The reliability (Cronbach's alpha) for the three subscales was 0.76, 0.72 and 0.55, respectively., Conclusion: Emotional intelligence is a multifactorial construct (three factors). The bilingual version of the SSREIS is a valid and reliable measure of trait emotional intelligence in an undergraduate Arab medical student population.

The Job Demands-Resources model (JD-R model) was used as the theoretical basis of a tailormade questionnaire to measure the psychosocial work environment and personal resources of recently graduated veterinary professionals. According to the JD-R model, two broad categories of work characteristics that determine employee wellbeing can be distinguished: job demands and job resources. Recently, the JD-R model has been expanded by integrating personal resource measures into the model. Three semistructured group interviews with veterinarians active in different work domains were conducted to identify relevant job demands, job resources and personal resources. These demands and resources were organised in themes (constructs). For measurement purposes, a set of questions ('a priori scale') was selected from the literature for each theme. The full set of a priori scales was included in a questionnaire that was administered to 1760 veterinary professionals. Exploratory factor analysis and reliability analysis were conducted to arrive at the final set of validated scales (final scales). 860 veterinarians (73 per cent females) participated. The final set of scales consisted of seven job demands scales (32 items), nine job resources scales (41 items), and six personal resources scales (26 items) which were considered to represent the most relevant potential predictors of work-related wellbeing in this occupational group. The procedure resulted in a tailormade questionnaire: the Veterinary Job Demands and Resources Questionnaire (Vet-DRQ). The use of valid theory and validated scales enhances opportunities for comparative national and international research.

With the aim to assess levels of burnout and work engagement in junior veterinarians and identify predictors of burnout and work engagement in male and female veterinarians, 1760 veterinarians who had graduated in The Netherlands between 1999 and 2009, received an electronic questionnaire. Veterinarians numbering 860 (73 per cent females) participated. Levels of exhaustion, cynicism and work engagement were significantly lower compared to the norm group (a random sample of the Dutch working population). Male veterinarians were less exhausted and more engaged than female veterinarians. Exhaustion decreased over the years. Job demands positively related to exhaustion were work-home interference and workload. Job resources positively related to work engagement were opportunities for professional development and skills discretion (ie, the ability to use and develop skills on the job. Personal resources explained more of the variance in work engagement of female and male veterinarians (31 per cent and 42 per cent) than of the variance in exhaustion (19 per cent and 21 per cent) and cynicism (19 per cent and 10 per cent). Personal resources positively related to work engagement were self-efficacy and proactive behaviour. Relative importance analysis revealed differences between men and women in the importance of various job demands, job resources and personal resources in explaining burnout and engagement in young veterinary professionals.

Weaknesses in the nature of rater judgments are generally considered to compromise the utility of workplace-based assessment (WBA). In order to gain insight into the underpinnings of rater behaviours, we investigated how raters form impressions of and make judgments on trainee performance. Using theoretical frameworks of social cognition and person perception, we explored raters' implicit performance theories, use of task-specific performance schemas and the formation of person schemas during WBA. We used think-aloud procedures and verbal protocol analysis to investigate schema-based processing by experienced (N = 18) and inexperienced (N = 16) raters (supervisor-raters in general practice residency training). Qualitative data analysis was used to explore schema content and usage. We quantitatively assessed rater idiosyncrasy in the use of performance schemas and we investigated effects of rater expertise on the use of (task-specific) performance schemas. Raters used different schemas in judging trainee performance. We developed a normative performance theory comprising seventeen inter-related performance dimensions. Levels of rater idiosyncrasy were substantial and unrelated to rater expertise. Experienced raters made significantly more use of task-specific performance schemas compared to inexperienced raters, suggesting more differentiated performance schemas in experienced raters. Most raters started to develop person schemas the moment they began to observe trainee performance. The findings further our understanding of processes underpinning judgment and decision making in WBA. Raters make and justify judgments based on personal theories and performance constructs. Raters' information processing seems to be affected by differences in rater expertise. The results of this study can help to improve rater training, the design of assessment instruments and decision making in WBA.

The influence of problem-based learning (PBL) and open-book tests on long-term knowledge retention is unclear and subject of discussion. Hypotheses were that PBL as well as open-book tests positively affect long-term knowledge retention. Four progress test results of fifth and sixth-year medical students (n = 1,648) of three medical schools were analyzed. Two schools had PBL driven curricula, and the third one had a traditional curriculum (TC). One of the PBL schools (PBLob) used a combination of open-book (assessing backup knowledge) and closed-book tests (assessing core knowledge); the other two schools (TC and PBLcb) only used closed-book tests. The items of the progress tests were divided into core and backup knowledge. T tests (with Bonferroni correction) were used to analyze differences between curricula. PBL students performed significantly better than TC students on core knowledge (average effect size (av ES) = 0.37-0.74) and PBL students tested with open-book tests scored somewhat higher than PBL students tested without such tests (av ES = 0.23-0.30). Concerning backup knowledge, no differences were found between the scores of the three curricula. Students of the two PBL curricula showed a substantially better long-term knowledge retention than TC students. PBLob students performed somewhat better on core knowledge than PBLcb students. These outcomes suggest that a problem-based instructional approach in particular can stimulate long-term knowledge retention. Distinguishing knowledge into core and backup knowledge and using open-book tests alongside closed-book tests could enhance long-term core knowledge retention.

Background: The Dutch postgraduate medical training has been revised to focus on seven competencies. The role as manager is one of these competencies. Recent studies show that this competency receives little attention during the residency training. In an earlier study, we discovered that residents perceived their competency as managers to be moderate., Aim: In this study, we investigated how medical specialists perceived the managerial competencies of medical residents and their need for management education., Methods: In September 2010, a 46-item questionnaire was designed which examined medical specialists' perceptions of the competency and needs of residents in the field of medical management. Two hundred ninety-eight specialists were invited via email to participate., Results: Hundred twenty-nine specialists (43.3%) responded to our survey. They rated the residents' competencies in contract negotiating skills, knowledge of the healthcare system, and specialist department poorly. They felt that residents were competent in updating their medical knowledge. Ninety-four percent reported a need for training in management among residents. Preferred topics were time management and healthcare organization. The preferred training method was a workshop given during residency by an extramural expert., Conclusion: Dutch medical specialists perceive the management competencies of residents in some areas to be inadequate. They feel that training in medical management during residency is necessary.

The drive to quality-manage medical education has created a need for valid measurement instruments. Validity evidence includes the theoretical and contextual origin of items, choice of response processes, internal structure, and interrelationship of a measure's variables. This research set out to explore the validity and potential utility of an 11-item measurement instrument, whose theoretical and empirical origins were in an Experience Based Learning model of how medical students learn in communities of practice (COPs), and whose contextual origins were in a community-oriented, horizontally integrated, undergraduate medical programme. The objectives were to examine the psychometric properties of the scale in both hospital and community COPs and provide validity evidence to support using it to measure the quality of placements. The instrument was administered twice to students learning in both hospital and community placements and analysed using exploratory factor analysis and a generalizability analysis. 754 of a possible 902 questionnaires were returned (84% response rate), representing 168 placements. Eight items loaded onto two factors, which accounted for 78% of variance in the hospital data and 82% of variance in the community data. One factor was the placement learning environment, whose five constituent items were how learners were received at the start of the placement, people's supportiveness, and the quality of organisation, leadership, and facilities. The other factor represented the quality of training-instruction in skills, observing students performing skills, and providing students with feedback. Alpha coefficients ranged between 0.89 and 0.93 and there were no redundant or ambiguous items. Generalisability analysis showed that between 7 and 11 raters would be needed to achieve acceptable reliability. There is validity evidence to support using the simple 8-item, mixed methods Manchester Clinical Placement Index to measure key conditions for undergraduate medical students' experience based learning: the quality of the learning environment and the training provided within it. Its conceptual orientation is towards Communities of Practice, which is a dominant contemporary theory in undergraduate medical education.

There has been increasing use and significance of progress testing in medical education. It is used in many ways and with several formats to reflect the variety of curricula and assessment purposes. These developments have occurred alongside a recognised sensitivity for error variance inherent in multiple choice tests from which challenges to its validity and reliability have arisen. This Guide presents a generic, systemic framework to help identify and explore improvements in the quality and defensibility of progress test data. The framework draws on the combined experience of the Dutch consortium, an individual medical school in the United Kingdom, and the bulk of the progress test literature to date. It embeds progress testing as a quality-controlled assessment tool for improving learning, teaching and the demonstration of educational standards. The paper describes strengths, highlights constraints and explores issues for improvement. These may assist in the establishment of potential or new progress testing in medical education programmes. They can also guide the evaluation and improvement of existing programmes.

Traditional psychometric approaches towards assessment tend to focus exclusively on quantitative properties of assessment outcomes. This may limit more meaningful educational approaches towards workplace-based assessment (WBA). Cognition-based models of WBA argue that assessment outcomes are determined by cognitive processes by raters which are very similar to reasoning, judgment and decision making in professional domains such as medicine. The present study explores cognitive processes that underlie judgment and decision making by raters when observing performance in the clinical workplace. It specifically focuses on how differences in rating experience influence information processing by raters. Verbal protocol analysis was used to investigate how experienced and non-experienced raters select and use observational data to arrive at judgments and decisions about trainees' performance in the clinical workplace. Differences between experienced and non-experienced raters were assessed with respect to time spent on information analysis and representation of trainee performance; performance scores; and information processing--using qualitative-based quantitative analysis of verbal data. Results showed expert-novice differences in time needed for representation of trainee performance, depending on complexity of the rating task. Experts paid more attention to situation-specific cues in the assessment context and they generated (significantly) more interpretations and fewer literal descriptions of observed behaviors. There were no significant differences in rating scores. Overall, our findings seemed to be consistent with other findings on expertise research, supporting theories underlying cognition-based models of assessment in the clinical workplace. Implications for WBA are discussed.

Background: Feedback to aid teachers in improving their teaching requires validated evaluation instruments. When implementing an evaluation instrument in a different context, it is important to collect validity evidence from multiple sources., Aim: We examined the validity and reliability of the Maastricht Clinical Teaching Questionnaire (MCTQ) as an instrument to evaluate individual clinical teachers during short clinical rotations in veterinary education., Methods: We examined four sources of validity evidence: (1) Content was examined based on theory of effective learning. (2) Response process was explored in a pilot study. (3) Internal structure was assessed by confirmatory factor analysis using 1086 student evaluations and reliability was examined utilizing generalizability analysis. (4) Relations with other relevant variables were examined by comparing factor scores with other outcomes., Results: Content validity was supported by theory underlying the cognitive apprenticeship model on which the instrument is based. The pilot study resulted in an additional question about supervision time. A five-factor model showed a good fit with the data. Acceptable reliability was achievable with 10-12 questionnaires per teacher. Correlations between the factors and overall teacher judgement were strong., Conclusions: The MCTQ appears to be a valid and reliable instrument to evaluate clinical teachers' performance during short rotations.

Background: It is often assumed that the way teachers approach their teaching is determined by the way they think about learning. This study explores how teachers of an undergraduate medical programme (UMP) think about learning, how they approach teaching and whether their conceptions of learning relate to their teaching approaches., Methods: Quantitative data of academic teachers involved in the undergraduate programme in medicine were collected and analysed. We used a questionnaire designed to measure teachers' conceptions of their own learning (COL) and of student learning as well as teachers' approaches to teaching (AT)., Results: Teachers of the medical undergraduate programme hold a variety of COL, of how students learn and their AT. No significant correlations were found between teachers' conceptions of learning and their AT., Conclusions: Although UMP teachers' ideas on learning and teaching are very diverse, some of their conceptions are interrelated. Teachers' ideas on their own learning is sometimes - but not always - related to how they think about student learning. But most importantly, the way UMP teachers think about learning is not automatically converted into the way they approach teaching.

Objective: To assess the quality of the content of reports of telephone consultations at out-of-hours centres and to investigate to what extent the reports reflect the actual telephone consultation., Design and Setting: Cross-sectional qualitative study; 17 out-of-hours centres in The Netherlands., Method: To assess the quality of the content of reports, a focus group developed the Reason for calling, Information gathered, Care advice given, Evaluation of the care advice with the patient (RICE) report rating instrument. Telephone Incognito Standardised Patients presented seven different clinical problems three times to 17 out-of-hours centres. All calls were recorded and transcribed. The out-of-hours centres being called were asked for a copy of the report of the call. The authors assessed the quality of the content of the reports and compared this with the transcripts., Results: The out-of-hours centres returned a report for 78% of the 357 calls. For the remaining 22% of the calls, no report was written. Reports contained almost always information about the medical reason for calling but little information about details of the clinical history. Patients' expectation, personal situation or perception of the care advice was seldom documented. In all but one out-of-hours centre, answers to obligatory questions were reported by triagists, although they had not been asked, varying between 1% and 54% of all questions entered. Triagists entered a subjective evaluation of a patients' condition in 12% of the reports., Conclusion: Reports of telephone consultations of out-of-hours centres contained little information on patients' clinical and personal condition. This could potentially endanger patients' continuity of care and might pose legal consequences for the triagist.

Background: Medical students increasingly participate in rotations in primary care settings, such as general practices. Although general practices can differ markedly from hospital settings, research on the instructional quality of general practice rotations is relatively scarce., Aim: We conducted a study to identify which aspects make a significant contribution to the instructional quality of general practice clerkships, as perceived by students., Method: After completing their general practice attachment, 155 fifth-year medical students filled out an evaluation questionnaire. Exploratory factor analysis and reliability analysis identified clusters of correlated independent variables. Subsequent regression analysis revealed the relations between the reduced set of independent variables and the dependent variable 'Instructional quality'., Results: Both the quality of supervision and the size and diversity of the patient mix substantially affected students' experienced instructional quality. Opportunities and facilities to perform independently were correlated with instructional quality, but did not affect the instructiveness directly., Conclusions: Supervision, patient mix and independence are crucial factors for learning in general practice. This is consistent with findings in hospital settings. The perceived quality of instruction hinges on supervision, which is not only the variable most strongly related to instructional quality, but which also affects both the patient mix and students' independence.

Background: Changing concepts of education have led many medical schools to adopt student-centred approaches to teaching, requiring different teaching competencies than more traditional approaches., Aims: The aim of this study was to investigate whether participation in a faculty development (FD) programme had a positive effect on veterinary medical teachers' perceptions of their competence in seven different teaching roles., Method: All teaching staff of a veterinary medical school (251) were invited to complete a questionnaire asking about their perceived competence in seven teaching roles. A stepwise multiple linear regression analysis examined the effect of the completion of a FD programme on perceived teaching competence., Results: There was a significant positive effect of the FD programme on teachers' perceived competence in majority of the teaching roles at issue., Conclusions: FD appeared to have a positive effect on the perceived competence of veterinary medical teachers. Further research should investigate whether FD actually results in improved teaching performance.

In a previous study, we established that compared to a written case, a video case enhances observable cognitive processes in the verbal interaction in a postgraduate problem-based learning format. In a new study we examined non-observable cognitive processes using a stimulated recall procedure alongside a reanalysis of the data from the first study. We examined the development of shared cognition as reflected in collaborative concept link formation, an approach to connecting a series of concepts related to a particular topic. Eleven paediatric residents were randomly allocated to two groups. After both analysing the same written case vignette, one group watched a video of the case in the vignette and the other group read a written description of the video. Both groups then reanalysed the vignette. After the group sessions, time-logged transcripts were made of the verbal interaction in both groups and all residents individually took part in a stimulated recall procedure. Causal reasoning concept links were labelled as individual or collaborative depending on whether they originated from individual residents or were directly elicited by verbal utterances from others. The video led to a significantly increased frequency ratio (after intervention: before intervention) of collaborative concept links but did not affect the frequency of individual concept links. This novel process approach to chronological registration of concept link formation offered additional evidence that shared cognition by means of co-elaboration of concept formation is stimulated by the use of patient video recordings in small group learning.

Aim: Aim of this study is to elucidate which standard setting method is optimal to prevent incompetent students to pass and competent students to fail a dental Objective Structured Clinical Examination (OSCE)., Material and Methods: An OSCE with 14 test stations was used to assess the performance of 119 third year dental students in a training group practice. To establish the pass/fail standard per station, three standard setting methods were applied: the Angoff I method, the modified Angoff II with reality check and the Borderline Regression (BR) method. For the final decision about passing or failing the complete OSCE, three methods were compared: total compensatory (TC), a partial compensatory (PC) within clusters of competence and a non-compensatory (NC) model. The reliability of the pass/fail standard of the three methods was indicated by the root mean square error (RMSE). As a criterion measure, a sample of the students (n = 89) was rated in the clinic by their instructors and accordingly these students were divided into two groups: competent and incompetent students. The students' clinical rating (considered for this study as 'true qualification') was compared with the pass-fail classification resulting from the OSCE. Undeserved passing of an incompetent student was considered as more damaging than failing a competent student., Results: The BR method showed more acceptable results than the two Angoff methods. In terms of pass rate the BR method showed the highest pass rates: for the TC model the Angoff method I and II and the BR showed pass rates of 86.6%, 86.6% and 97.5% respectively. For the PC model the pass rates were 30.3%, 34.5% and 61.3%, and for the NC model the pass rates were 0.8%, 1.7% and 7.6%. The BR method showed lower RMSEs (higher reliability): for the TC model the RMSEs were 1.3%, 1.0% and 0.3% for the Angoff I, Angoff II and BR method respectively, and for the PC model the RMSE of the clusters of competence range was 2.0-3.7% for Angoffs I; 1.8-2.2% for Angoff II and 0.6-0.7% for the BR method. In terms of incorrect decisions, the BR method had a higher loss due to incorrect decisions for the TC model than for the PC model which is in accordance with the results of other studies in medical education., Conclusions: Therefore we conclude that the BR method in a PC model provides defensible pass/fail standards and seems to be the optimal choice for OSCEs in health education.

Background: Changing a curriculum raises the question whether the results, new curriculum student outcomes, are different from old curriculum student outcomes., Aims: To see whether different curricula produce different outcomes, we compared test and questionnaire results of two cohorts. We wanted to know if there is a difference on knowledge and skills test results, and on the number of times students practiced their skills during their final internships., Method: We used two validated test instruments: the Dutch Progress Test (PT) and the Objective Structured Clinical Examination (OSCE). For reporting their skills practice, we asked students of both cohorts to fill out a basic skills questionnaire., Results: We found no significant difference between both cohorts on the results of their knowledge test and their report on skills practice. On the OSCE, students from the new curriculum cohort scored significantly higher than old curriculum students., Conclusion: Curriculum change can lead to improvements in graduating students' outcome results.

Aim: The first aim was to study the reliability of a dental objective structured clinical examination (OSCE) administered over multiple days, and the second was to assess the number of test stations required for a sufficiently reliable decision in three score interpretation perspectives of a dental OSCE administered over multiple days., Materials and Methods: In four OSCE administrations, 463 students of the year 2005 and 2006 took the summative OSCE after a dental course in comprehensive dentistry. The OSCE had 16-18 5-min stations (scores 1-10), and was administered per OSCE on four different days of 1 week. ANOVA was used to test for examinee performance variation across days. Generalizability theory was used for reliability analyses. Reliability was studied from three interpretation perspectives: for relative (norm) decisions, for absolute (domain) and pass-fail (mastery) decisions. As an indicator of reproducibility of test scores in this dental OSCE, the standard error of measurement (SEM) was used. The benchmark of SEM was set at <0.51. This is corresponding to a 95% confidence interval (CI) of <1 on the original scoring scale that ranged from 1 to 10., Results: The mean weighted total OSCE score was 7.14 on a 10-point scale. With the pass-fail score set at 6.2 for the four OSCE, 90% of the 463 students passed. There was no significant increase in scores over the different days the OSCE was administered. 'Wished' variance owing to students was 6.3%. Variance owing to interaction between student and stations and residual error was 66.3%, more than two times larger than variance owing to stations' difficulty (27.4%). The SEM norm was 0.42 with a CI of +/-0.83 and the SEM domain was 0.50, with a CI of +/-0.98. In order to make reliable relative decisions (SEM <0.51), the use of minimal 12 stations is necessary, and for reliable absolute and pass-fail decisions, the use of minimal 17 stations is necessary in this dental OSCE., Conclusions: It appeared reliable, when testing large numbers of students, to administer the OSCE on different days. In order to make reliable decisions for this dental OSCE, minimum 17 stations are needed. Clearly, wide sampling of stations is at the heart of obtaining reliable scores in OSCE, also in dental education.

Background: To establish credible, defensible and acceptable passing scores for written tests is a challenge for health profession educators. Angoff procedures are often used to establish pass/fail decisions for written and performance tests. In an Angoff procedure judges' expertise and professional skills are assumed to influence their ratings of the items during standard-setting. The purpose of this study was to investigate the impact of judges' item-related knowledge on their judgement of the difficulty of items, and second, to determine the stability of differences between judges., Method: Thirteen judges were presented with two sets of 60 items on different occasions. They were asked to not only judge the difficulty of the items but also to answer them, without the benefit of the answer key. For each of the 120 items an Angoff estimate and an item score were obtained. The relationship between the Angoff estimate and the item score was examined by applying a regression analysis to the 60 items (Angoff estimate, score) for each judge at each occasion., Results and Conclusions: This study shows that in standard-setting the individual judgement of the individual item is not only a reflection of the difficulty of the item but also of the inherent stringency of the judge and his/her subject-related knowledge. Considerable variation between judges in their stringency was found, and Angoff estimates were significantly affected by a judge knowing or not knowing the answer to the item. These findings stress the importance of a careful selection process of the Angoff judges when making pass/fail decisions in health professions education. They imply that judges should be selected who are not only capable of conceptualising the 'minimally competent student', but who would also be capable of answering all the items.

Aim of the Study: Several studies using a variety of assessment approaches have demonstrated that young doctors possess insufficient resuscitation competence. The aims of this study were to assess newly graduated doctors' resuscitation competence against an internationally recognised standard and to study whether teaching site affects their resuscitation competence., Materials and Methods: The entire cohort of medical students from Copenhagen University expected to graduate in June 2006 was invited to participate in the study. Participants' ALS-competence was assessed using the Advanced Life Support Provider (ALS) examination standards as issued by the European Resuscitation Council (ERC). The emergency medicine course is conducted at three different university hospital teaching sites and teaching and assessment might vary across sites, despite the common end objectives regarding resuscitation teaching issued by the university., Results: Participation was accepted by 154/240 (64%) graduates. Only 23% of the participants met the ALS pass criteria. They primarily lacked skills in managing cardiopulmonary arrest. There were significant differences in ALS-competence between teaching sites., Conclusion: Newly graduated doctors do not have sufficient competence in managing cardiopulmonary arrests according to the current guidelines published by ERC. There were significant differences in ALS-competence between sites. Change in teaching and assessment practice in undergraduate emergency medicine courses is needed in order to increase the level of ALS-competence of newly graduated doctors.

Background: Introducing innovative curricular designs can be evaluating by scrutinizing the learning patterns students use., Aim: Studying the potential of Vermunt's Inventory of Learning Styles (ILS) in detecting differences in student learning patterns in different medical curricula., Methods: Cross-sectional between-subjects comparison of ILS-scores in third-year medical students in a conventional, an integrated contextual and a PBL-curriculum using one-way post hoc ANOVA., Results: Response rate was 85%: 197 conventional, 130 integrated contextual and 301 PBL students. The results show a differential impact from the three curricula. In relation to processing strategies, the students in the problem-based curriculum showed less rote learning and rehearsing, greater variety in sources of knowledge used and less ability to express study content in a personal manner than did the students in the conventional curriculum. The students of the integrated contextual curriculum showed more structuring of subject matter by integrating different aspects into a whole. In relation to regulation strategies, the students in the problem-based curriculum showed significantly more self-regulation of learning content and the students in the integrated contextual curriculum showed lower levels of regulation. As to learning orientations, the students in the problem-based curriculum showed less ambivalence and the students of the conventional curriculum were less vocationally oriented., Conclusion: The study provides empirical support for expected effects of traditional and innovative curricula which thus far were not well supported by empirical studies.

Purpose: To examine problem-based learning (PBL) students' views on the added value of video cases compared to text-based cases in the pre-clinical phase of undergraduate medical education and on the conditions for productive use of video in tutorial group discussions., Method: Participants were 2nd-year students who had completed a PBL programme featuring video cases. Three groups of 6-8 randomly selected students participated in focus-group interviews guided by a moderator using a 'questioning route'. The interviews were audiotaped, transcribed and analysed. The summary reports were approved by the students., Results: According to the students, the video cases enabled them to create realistic mental pictures of disorders, provided integrated pictures of patients as people, which challenged them to elaborate the cases seriously and were more memorable than text-based cases. Cases that students perceived as fostering the productive use of video were neither too directive nor too complete, tailored to students' prior knowledge, short, varied in design and complementary to other materials. The cases should be viewed in a structured, purposeful manner, with cues, instructions and prompts to focus attention on essential issues., Conclusion: The video cases were generally perceived as a valuable stimulus for group discussions in PBL. However, productive use depended on specific conditions. Many of the advantages and conditions mentioned are supported by earlier non-empirical claims in the literature or can be explained by theory and empirical studies on symbol systems. Future observational studies should address the effects of specific attributes of video as a medium.

Objectives: To determine whether self-directed learning about (electronic) patient records during a PBL (problem-based learning) block, dealing with the content of disciplines concerned with the diagnosis and therapy of diseases of the abdomen, increased the knowledge of the students with respect to the patient records., Methods: At the beginning and at the end of the ten-week block the same questionnaire was offered to the students (180). Cohen's d for effect size was used to determine the increase in knowledge., Results: For those students that answered the questionnaire twice (53), a Cohen's d of 0.94 was obtained., Conclusions: The knowledge of the students concerning the advantages and limitations of (electronic) patient records increased significantly. The corresponding effect size was large.

Background: Doctor-patient communication is an essential component of general practice. Improvement of GPs' communication patterns is an important target of training programmes. Available studies have so far failed to provide conclusive evidence of the effectiveness of educational interventions to improve doctor-patient communication., Aim: To examine the effectiveness of a learner-centred approach that focuses on actual needs, to improve GPs' communication with patients., Design of Study: Randomised controlled trial., Setting: One hundred volunteer GPs in the Netherlands., Method: The intervention identified individual GPs' deficiencies in communication skills by observing authentic consultations in their own surgery. This performance assessment was followed by structured activities in small group meetings, aimed at remedying the identified shortcomings. Outcomes were measured using videotaped consultations in the GPs' own surgery before and after the intervention. Communication skills were rated using the MAAS-Global, a validated checklist., Results: The scores in the intervention group demonstrated a significant improvement compared with those of the control group (95% confidence interval = 0.04 to 0.75). The effect size was moderate to large (d-value = 0.66). The level of participation significantly contributed to the effectiveness. Largest improvement was found on patient-centred communication skills., Conclusion: The approach of structured individual improvement activities based on performance assessment is more effective in improving communication skills than current educational activities.

Objective: To investigate whether adding a brief video case instead of an equivalent written text improves the cognitive and metacognitive processes (data exploration, theory building, theory evaluation and metareasoning) of residents in problem-based learning., Subjects: Paediatric residents., Setting: Department of Paediatrics, Arhus University Hospital, Skejby, Denmark., Methods: Eleven residents were each assigned to 1 of 2 groups. Both groups analysed an identical vignette of a patient case. Immediately after this, 1 group watched a 2.5-minute video recording and the other group read a description of the same video recording. The groups then reanalysed the case. Thinking processes were tapped by recording and analysing the verbal group interaction. The frequencies of clause categories were calculated and compared using chi-square tests., Results: The verbal interaction showed statistically significant improvements in data exploration, theory building and theory evaluation after the video case., Conclusions: The greater improvement in clause frequency after the video case compared with the equivalent text suggests an improvement in data exploration, theory building and theory evaluation. The use of patient video recordings may be a valuable supplement to postgraduate paediatric training, particularly pertaining to movement disorders.

Purpose: To evaluate the effectiveness of undergraduate medical education in the domains of psychiatry and behavioural sciences, we examined the growth of knowledge in those disciplines in a 6-year, problem-based learning (PBL) curriculum. Psychiatry and behavioural sciences are taught in the 4 preclinical years and in the psychiatric clerkship. The integrative nature of this PBL curriculum led us to hypothesise that the knowledge growth curves for these disciplines are similar and show a steady upward trend throughout the curriculum., Methods: All items pertaining to psychiatry and behavioural sciences in the progress tests administered in the period from September 1993 through May 2001 were identified. For those items, the percentage of correct scores in the 6 year groups were considered a multivariate observation reflecting knowledge growth across the 6-year programme., Results: Knowledge growth for psychiatry and behavioural sciences increased significantly, from 12% to 59% and from 28% to 60%, respectively, between Year 1 and the end of Year 6. Apparently, students know more about behavioural sciences than about psychiatry when they enter medical school, but this difference vanishes in the last 2 years of training. Moreover, the growth curves for psychiatry and behavioural sciences started to level off after Years 3 and 4, respectively, with no additional significant growth in any of the later years., Conclusions: Psychiatry and behavioural sciences showed different patterns of knowledge growth and the 2 growth curves levelled off in Years 5 through 6. Because a student-centred, horizontally and vertically integrated PBL curriculum is aimed at effecting steady growth in knowledge in all disciplines, the slowdown in growth in the later years was among the reasons for initiating a major curricular innovation in 2001.

Context: Continuing professional development (CPD) of general practitioners., Objective: Criterion-referenced standards for assessing performance in the real practice of general practitioners (GPs) should be available to identify learning needs or poor performers for CPD. The applicability of common standard setting procedures in authentic assessment has not been investigated., Methods: To set a standard for assessment of GP-patient communication with video observation of daily practice, we investigated 2 well known examples of 2 different standard setting approaches. An Angoff procedure was applied to 8 written cases. A borderline regression method was applied to videotaped consultations of 88 GPs. The procedures and outcomes were evaluated by the applicability of the procedure, the reliability of the standards and the credibility as perceived by the stakeholders, namely, the GPs., Results: Both methods are applicable and reliable; the obtained standards are credible according to the GPs., Conclusions: Both modified methods can be used to set a standard for assessment in daily practice. The context in which the standard will be used - i.e. the specific purpose of the standard, the moment the standard must be available or if specific feedback must be given - is important because methods differ in practical aspects.

The practice of assessment is governed by an interesting paradox. On the one hand good assessment requires substantial resources which may exceed the capacity of a single institution and we have reason to doubt the quality of our in-house examinations. On the other hand, our parsimonity with regard to our resources makes us reluctant to pool efforts and share our test material. This paper reports on an initiative to share test material across different medical schools. Three medical schools in The Netherlands have successfully set up a partnership for a specific testing method: progress testing. At present, these three schools collaboratively produce high-quality test items. The jointly produced progress tests are administered concurrently by these three schools and one other school, which buys the test. The steps taken in establishing this partnership are described and results are presented to illustrate the unique sort of information that is obtained by cross-institutional assessment. In addition, plans to improve test content and procedure and to expand the partnership are outlined. Eventually, the collaboration may even extend to other test formats. This article is intended to give evidence of the feasibility and exciting potential of between school collaboration in test development and test administration. Our experiences have demonstrated that such collaboration has excellent potential to combine economic benefit with educational advantages, which exceed what is achievable by individual schools.

Purpose: Earlier studies of absolute standard setting procedures for objective structured clinical examinations (OSCEs) show inconsistent results. This study compared a rational and an empirical standard setting procedure. Reliability and credibility were examined first. The impact of a reality check was then established., Methods: The OSCE included 16 stations and was taken by trainees in their final year of postgraduate training in general practice and experienced general practitioners. A modified Angoff (independent judgements, no group discussion) with and without a reality check was used as a rational procedure. A method related to the borderline group procedure, the borderline regression (BR) method, was used as an empirical procedure. Reliability was assessed using generalisability theory. Credibility was assessed by comparing pass rates and by relating the passing scores to test difficulty., Results: The passing scores were 73.4% for the Angoff procedure without reality check (Angoff I), 66.0% for the Angoff procedure with reality check (Angoff II) and 57.6% for the BR method. The reliabilities (expressed as root mean square errors) were 2.1% for Angoffs I and II, and 0.6% for the BR method. The pass rates of the trainees and GPs were 19% and 9% for Angoff I, 66% and 46% for Angoff II, and 95% and 80% for the BR method, respectively. The correlation between test difficulty and passing score was 0.69 for Angoff I, 0.88 for Angoff II and 0.86 for the BR method., Conclusion: The BR method provides a more credible and reliable standard for an OSCE than a modified Angoff procedure. A reality check improves the credibility of the Angoff procedure but does not improve its reliability.

Introduction: An earlier study showed that an Angoff procedure with > or = 10 recently graduated students as judges can be used to estimate the passing score of a progress test. As the acceptability and feasibility of this approach are questionable, we conducted an Angoff procedure with test item writers as judges. This paper reports on the reliability and credibility of this procedure and compares the standards set by the two different panels., Methods: Fourteen item writers judged 146 test items. Recently graduated students had assessed these items in a previous study. Generalizability was investigated as a function of the number of items and judges. Credibility was judged by comparing the pass/fail rates associated with the Angoff standard, a relative standard and a fixed standard. The Angoff standards obtained by item writers and graduates were compared., Results: The variance associated with consistent variability of item writers across items was 1.5% and for graduate students it was 0.4%. An acceptable error score required 39 judges. Item-Angoff estimates of the two panels and item P-values correlated highly. Failure rates of 57%, 55% and 7% were associated with the item writers' standard, the fixed standard and the graduates' standard, respectively., Conclusion: The graduates' and the item writers' standards differed substantially, as did the associated failure rates. A panel of 39 item writers is not feasible. The item writers' passing score appears to be less credible. The credibility of the graduates' standard needs further evaluation. The acceptability and feasibility of a panel consisting of both students and item writers may be worth investigating.

Objective: Asynchronous electrical activation of the left ventricle (LV), induced by ventricular pacing (VP), reduces mechanical load in early- and enhances it in late-activated regions. Consequently, chronic VP leads to asymmetric hypertrophy. We investigated whether such locally induced myocardial hypertrophy also occurs in the presence of pressure overload hypertrophy (POH)., Methods: POH was induced by aortic banding in puppies. At age 9 months, seven dogs were paced at the right ventricular (RV) apex at physiological heart rate for 6 months (POH-pace group), while four POH dogs served as POH-control group. Changes in volume of the LV cavity and the total LV wall and of five LV wall sectors were measured by means of 2D-echocardiography and X-ray marker detection., Results: During the last 6 months of the protocol the volume of the five LV wall sectors increased in the POH-control group, ranging from 27+/-9 to 30+/-5% (mean+/-S.D.). In POH-pace animals sector wall volume in the four sectors at intermediate to long distance from the pacing site increased to a similar extent (ranging from 31+/-16 to 35+/-17%), but wall volume in the early-activated apical septum increased significantly less (17+/-21%). In these hearts myocyte diameter was significantly smaller in the apical septum than in the lateral LV wall. The regional difference in wall volume changes (19+/-21%) was significantly smaller in the POH-pace group than in chronically paced, non-hypertrophic, canine hearts in a previous study from our laboratory (43+/-14%)., Conclusions: In hypertrophying hearts chronic pacing at the RV apex suppresses the development of hypertrophy in the early-activated apical septum but does not cause additional hypertrophy in late-activated regions, as is the case in non-hypertrophic hearts. The latter suggests that the local growth response is reduced in hypertrophying hearts.

Objective: To examine whether successful coronary reperfusion after thrombolytic treatment in patients with confirmed acute myocardial infarction can be diagnosed from the plasma marker fatty acid binding protein (FABP), for either acute clinical decision making or retrospective purposes., Design: Retrospective substudy of the GUSTO trial., Setting: 10 hospitals in four European countries., Patients: 115 patients were treated with thrombolytic agents within six hours after the onset of acute myocardial infarction. Patency of the infarct related artery was determined by angiography within 120 minutes of the start of thrombolysis., Main Outcome Measures: First hour rate of increase in plasma FABP concentration after thrombolytic treatment, compared with increase in plasma myoglobin concentration and creatine kinase isoenzyme MB (CK-MB) activity. Infarct size was estimated from the cumulative release of the enzyme alpha hydroxybutyrate dehydrogenase in plasma during 72 hours, or from the sum of ST segment elevations on admission. Logistic regression analyses were performed to construct predictive models for patency., Results: Complete reperfusion (TIMI 3) occurred in 50 patients, partial reperfusion (TIMI 2) in 36, and no reperfusion (TIMI 0+1) in 29. Receiver operating characteristic (ROC) curve analyses showed that the best performance of FABP was obtained when TIMI scores 2 and 3 were grouped and compared with TIMI score 0+1. The performance of FABP as a reperfusion marker was improved by combining it with alpha hydroxybutyrate dehydrogenase infarct size, but not with an early surrogate of infarct size (ST segment elevation on admission). In combination with infarct size FABP performed as well as myoglobin (areas under the ROC curve 0.868 and 0.857, respectively) and better than CK-MB (area = 0.796). At optimum cut off levels, positive predictive values were 97% for FABP, 95% for myoglobin, and 89% for CK-MB (without infarct size, 87%, 88%, and 87%, respectively), and negative predictive values were 55%, 52%, and 50%, respectively (without infarct size, 44%, 42%, and 34%)., Conclusions: FABP and myoglobin perform equally well as reperfusion markers, and successful reperfusion can be assessed, with positive predictive values of 87% and 88%, or even 97% and 95% when infarct size is also taken into account. However, identification of non-reperfused patients remains a problem, as negative predictive values will generally remain below 70%.

Purpose: Educators who use standardized-patient-based (SP-based) tests may save resources by using sequential testing. In this approach, students take a short screening test; only those who fail take a second test. This study investigated whether sequential testing increases efficiency with only a minor decrease of validity., Method: In 1994-95, first- through fourth-year (Group 1) and sixth-year (Group 2) medical students at the University of Maastricht took SP-based tests. Each test took two days. In a simulation experiment based on the data from those tests, the authors considered the first day as the screening test and the second day as the second test. They investigated efficiency and validity as a function of the cutoff score of the screening test. They developed and evaluated a new method to determine the optimum cutoff score of the screening test, a method based on minimization of the loss represented by the (weighted) numbers of false positives and negatives in the screening test., Results: The negative predictive value (probability that a student would fail the complete test if he or she had failed the screening test) was low (<60%), while the positive predictive value was high (>96%). Accordingly, stringent pass/fail cutoff scores in the screening test (75% for Group 1 and 80% for Group 2) produced optimum results. Using those cutoff values, only 26% and 11% of 'the students would have had to take the complete test to get a "true" score, while only 0.2% and 0.0% of the students who passed the screening test went on to fail the complete test (false positives)., Conclusions: In a sequential SP-based test, the pass/fail cutoff score of the screening test should be stringent. This can considerably reduce testing time (30% to 40%), while keeping the percentage of false positives at an acceptably low level of less than 0.2%. As an alternative to receiver operator characteristic analysis, minimization of the loss function was found to be an appropriate method to determine the optimum cutoff value of the screening test.

Purpose: To compare four standard-setting procedures for an objective structure clinical examination (OSCE)., Methods: A 12-station OSCE was administered to 84 students in each of the final (fourth-) year medical classes of 1996 and 1997 at Dalhousie University Faculty of Medicine. Four standard-setting procedures (Angoff, borderline, relative, and holistic) were applied to the data to establish a cutoff score for a pass/fail decision., Results: The procedures yielded highly inconsistent results. The Angoff and borderline procedures gave similar results; however, the relative and holistic methods gave widely divergent results. The Angoff procedure yielded results reliable enough to use in decision making for a high-stakes examination, but would have required more judges or more stations., Conclusions: The Angoff and borderline procedures provide reasonable and defensible approaches to standard setting and are practical to apply by non-psychometricians in medical schools. Further investigation of the other procedures is needed.

Introduction: Progress testing is an assessment method that samples the complete domain of knowledge that is considered pertinent to undergraduate medical education. Because of the comprehensive nature of this test, it is very difficult to set a passing score. We obtained a progress test standard using an Angoff procedure with recent graduates as judges. This paper reports on the reliability and credibility of this approach., Methods: The Angoff procedure was applied to a sample of 146 progress test items. The items were judged by a panel of eight recently graduated students. Generalizability theory was used to investigate the reliability as a function of the number of items and judges. Credibility was judged by comparing the pass/fail rates resulting from the standard arrived at by the Angoff procedure with those obtained using a relative and a fixed standard., Results: The results indicate that an acceptable error score can be achieved, yielding a precision within one percentage on the scoring scale, by using 10 judges on a full-length progress test (i.e. 250 items). The pass/fail rates associated with the Angoff standard came closest to those of the relative standard, which takes variations in test difficulty into account. A high correlation was found between item-Angoff estimates and the item P-values., Conclusion: The results of this study suggest that the Angoff procedure, using recently graduated students as judges, is an appropriate standard setting method for a progress test.

An important assumption in 2D numerical models of skeletal muscle contraction involves deformation in the third dimension of the included muscle section. The present paper studies the often used plane strain description. Therefore, 3D muscle surface deformation is measured from marker displacements during isometric contractions at various muscle lengths. Longitudinal strains at superficial muscle fibers ( - 14 +/- 2.6% at L0, n = 57) and aponeurosis (0.8 +/- 0.9% at L0) decrease with increasing muscle length. The same holds for transverse muscle surface strains in superficial muscle fibers and aponeurosis, which are comparable at intermediate muscle length, but differ at long and short muscle length. Because transverse strains during isometric contraction change with initial muscle length, it is concluded that the effect of muscle length on muscle deformation cannot be studied in plane strain models. These results do not counteract the use of these models to study deformation in contractions with approximately - 9 % longitudinal muscle fiber strain, as transverse strain in superficial muscle fibers and in aponeurosis tissue is minimal in that case. Aponeurosis surface area change decreases with increasing initial muscle length, but muscle fiber surface area change is - 11%, independent of muscle length. Assuming incompressible muscle material, this means that strain perpendicular to the muscle surface equals 11%. Taking the relationship between transverse and longitudinal muscle fiber strain into account, it is hypothesized that superficial muscle fibers flatten during isometric contractions.

Cardiac tagging permits non-invasive study of myocardial motion with high accuracy. Unfortunately, tagging contrast is impaired at later heart phases due to longitudinal relaxation. Histogram modification is presented as a method for improving contrast in later, faded images of a tagging series by altering these images such that their intensity histograms approximate the shape of the first, unfaded image of the series. This technique greatly improves the contrast and facilitates automatic detection of tags. Furthermore, a method is described for automatically tracking tag positions in short-axis images of the left ventricle modulated with a tagging grid. The method differs from previously reported methods in that, in one single filtering process in the Fourier domain, both the grid crossings as well as the grid centers are detected, and thus increased sampling resolution is obtained. The method was validated by applying a mathematical model of left ventricular motion to tagged images of the thigh muscle. The average discrepancy between theoretically predicted and automatically detected tag positions was 0.04 +/- 0.17 mm (mean +/- SD).

Objectives: In multiple-choice tests using a 'don't-know' option the number of correct minus incorrect answers was used as the test score (formula scoring) in order to reduce the measurement error resulting from random guessing. In the literature diverging results are reported when comparing formula scoring and number-right scoring, the scoring method without the don't-know option., Design: To investigate which method was most appropriate, both scoring methods were used in true-false tests (block tests) taken at the end of a second- and third-year educational module (block). The students were asked to answer each item initially by choosing from the response options true, false or don't know, and secondly to replace all don't-know answers by a true-false answer., Setting: Maastricht University, The Netherlands., Subjects: Medical students., Results: The correct scores for the don't-know answered items were found to be 4.5% and 5.9%, respectively, higher than expected with pure random guesswork. This represents a source of bias with formula scoring, because students who were less willing to guess obtained lower scores. The average difference in the correct minus incorrect score for the two scoring methods (2.5%, P < 0.001, and 3.4%, P < 0. 001, respectively) indicates the size of the bias (compare: the standard deviation of the score equals 11%). Test reliability was higher with formula scoring (0.72 vs. 0.66 and 0.74 vs. 0.66), but the difference decreased when the test was restricted to items which were close to the core content of the block (0.81 vs. 0.77, resp. 0. 75 vs. 0.70)., Conclusions: In deciding what scoring method to use, less bias (number-right scoring) has to be weighed against higher reliability (formula scoring). Apart from these psychometric reasons educational factors must be considered.

Motion and deformation of the cardiac wall may be measured by following the positions of implanted radiopaque markers in three dimensions, using two x-ray cameras simultaneously. Regularly, calibration of the position measurement system is obtained by registration of the images of a calibration object, containing 10-20 radiopaque markers at known positions. Unfortunately, an accidental change of the position of a camera after calibration requires complete recalibration. Alternatively, redundant information in the measured image positions of stereo pairs can be used for calibration. Thus, a separate calibration procedure can be avoided. In the current study a model is developed that describes the geometry of the camera setup by five dimensionless parameters. Maximum Likelihood (ML) estimates of these parameters were obtained in an error analysis. It is shown that the ML estimates can be found by application of a nonlinear least squares procedure. Compared to the standard unweighted least squares procedure, the ML method resulted in more accurate estimates without noticeable bias. The accuracy of the ML method was investigated in relation to the object aperture. The reconstruction problem appeared well conditioned as long as the object aperture is larger than 0.1 rad. The angle between the two viewing directions appeared to be the parameter that was most likely to cause major inaccuracies in the reconstruction of the 3-D positions of the markers. Hence, attempts to improve the robustness of the method should primarily focus on reduction of the error in this parameter.

In anesthetized dogs with chronic, complete AV block we studied the characteristics of ventricular repolarization and refractoriness. Therefore, we determined: (1) steady-state values of ventricular effective refractory period (VERP), action potential duration (APD), and stimulus T interval (STI) before and after d-sotalol treatment at various pacing cycle lengths (PCLs); and (2) the dynamics of VERP, APD, and STI before and after d-sotalol treatment after the abrupt PCL decreases. VERP, APD, and STI showed a normal frequency dependency. All three parameters increased significantly after d-sotalol administration. During steady-state and dynamic measurements, STI was always longer than APD and APD was always longer than VERP in an individual animal, irrespective of PCL and conditions. Standard deviations of steady-state and dynamic values indicated a considerable interindividual variation. However, the dynamics of VERP, APD, and STI after an abrupt decrease in PCL were highly correlated (linear regression analysis: r2 > or = 0.93). The best mathematical model to describe these dynamics was a bi-exponential model (r2 > or = 0.98) with a very short first and a much longer second time constant. We found that there was a very consistent relation between VERP, APD, and STI, not only during steady-state but also in the dynamic situation after various abrupt PCL decreases. This relation does not change after the administration of d-sotalol. Therefore, STI could be used to predict steady-state and dynamic values of VERP and APD. Since STI can be made available online in implantable pacing systems this could lead to the development of new features in these devices.

During the ejection phase, motion of the left ventricular (LV) wall is such that all myocardial fibers shorten to the same extent. In a mathematical model of LV mechanisms it was found that this condition could be satisfied only if torsion around the long axis followed a unique function of the ratio of cavity volume to wall volume. When fiber shortening becomes non-uniform due to cardiac pathology, this pathology may be reflected in aberration of the torsional motion pattern. In the present study we investigated whether the predicted regular motion pattern could be found in nine healthy volunteers, using Magnetic Resonance Tagging. In two parallel short-axis cross-sections, displacement, rotation, and area ejection were derived from the motion of tags, attached non-invasively to the myocardium. Information from both sections was combined to determine area ejection, quantified as the change in the logarithm of the ratio of cavity area to wall area, and torsion, represented by the shear angle on the epicardium. Linear regression was applied to torsion as a function of area ejection. The slope thus found (-0.173 +/- 0.024 rad, mean +/- S.D.) was similar to the slope as predicted by the model of LV mechanics (-0.194 +/- 0.026 rad). In conclusion, the relation between area ejection and torsion could be assessed noninvasively in humans. In healthy volunteers, the relation was close to what was predicted by a mathematical model of LV mechanics, and also close to what was found earlier in experiments on animals.

Motion and deformation of an object may be quantified by following attached markers in video or cine frame sequences. When recording cardiac motion by video (256 x 256 pixels, 50 Hz), generally no more than approximately 20 markers can be followed due to difficulties in proper identification of marker images. In the present study we developed the lower rank (LR) tracking method which can automatically follow considerably more than 20 markers. The performance of the method was evaluated in computer simulations of naturally moving myocardial markers observed in a sequence of 60 video frames. White noise was added to the marker coordinates. Realistic loss of data due to detection failure was simulated by deleting a generated marker image when the distance to another marker image was below a given minimum value. In a test, realistic values were substituted for the noise level sigma (0.5 pixel) and the minimum marker distance dm (4 pixels). For numbers of markers ranging from 50 to 100, 95-90% of the detected marker images was correctly tracked. Less than 0.7% was part of a false track, i.e. a track containing images of different markers. Under less favourable conditions (sigma = 1 pixel; dm = 8 pixels) the method was robust: for 75 markers with 40% of the marker images missing, still 70% of the detected images was correctly tracked, while the fraction in false tracks did not increase. The LR tracking method appears reliable for automatic tracking of large amounts of moving markers in a sequence of video or cine frames.