Validity in teacher assessment. An exploration of the judgement processes of assessors

Assessment of teaching is currently becoming more and more common practice. As such assessment is generally based on complex, qualitative data from multiple sources (e.g., lesson plans, video-taped lessons, written reflections of the teacher on his or her performance), the overall quality of the assessment depends heavily on the judgement processes of assessors. Assessors have the essential tasks of consideration of evidence from separate sources and combination of this evidence to attain a coherent overall judgement. In the current research, the judgement processes of twenty-four assessors were analysed. All assessors judged the same student teacher, using a specific assessment procedure. The results of the research provide insight in the potential threats to the validity of the judgement process and of the assessment overall. An example of such a threat is a tendency to consider mainly confirmatory evidence for initial interpretations as opposed to also considering counterevidence or alternative interpretations. Assessors are not always aware of such threats, and even when they are, the do not always know how to overcome these threats. The results of this research have implications for ensuring the quality of assessment and for the preparation of assessors. Assessor training should explicitly be aimed at increasing awareness of the relevant judgement processes, specific threats to the quality of these processes and potential succesful strategies to overcome these threats.UBL - phd migration 201

Semi-quantitative assessment of right ventricular function in comparison to a 3D volumetric approach: A cardiovascular magnetic resonance study

Right ventricular (RV) volume measurements with cardiovascular magnetic resonance (CMR) is considered the gold standard, but acquisition and analysis remain timeconsuming. The aim of our study was therefore to investigate the accuracy and performance of a semi-quantitative assessment of RV function in CMR, compared to the standard quantitative approach. Seventy-five subjects with pulmonary hypertension (15), anterior myocardial infarction (15), inferior myocardial infarction (15), Brugada syndrome (15) and normal subjects (15) underwent cine CMR. RV end-systolic and enddiastolic volumes were determined to calculate RV ejection fraction (EF). Four-chamber cine images were used to measure tricuspid annular plane systolic excursion (TAPSE). RV fractional shortening (RVFS) was calculated by dividing TAPSE by the RV end-diastolic length. RV EF correlated significantly with TAPSE (r = 0.62, p < 0.01) and RVFS (r = 0.67, p < 0.01). Sensitivity to predict RV dysfunction was comparable between TAPSE and RVFS, with higher specificity for RVFS, but comparable areas under the ROC curve. Intra- and inter-observer variability of RV EF was better than TAPSE (3%/4% versus 7%/15%, respectively). For routine screening in clinical practice, TAPSE and RVFS seem reliable and easy methods to identify patients with RV dysfunction. The 3D volumetric approach is preferred to assess RV function for research purposes or to evaluate treatment response