Twelve tips to aid interpretation of post-assessment psychometric reports.

Post-assessments psychometric reports are a vital component of the assessment cycle to ensure that assessments are reliable, valid and fair to make appropriate pass-fail decisions. Students' scores can be summarised by examination of frequency distributions, central tendency measures and dispersion measures. Item discrimination indicies to assess the quality of items, and distractors that differentiate between students achieving or not achieving the learning outcomes are key. Estimating individual item reliability and item validity indices can maximise test-score reliability and validity. Test accuracy can be evaluated by assessing test reliability, consistency and validity and standard error of measurement can be used to measure the variation. Standard setting, even by experts, may be unreliable and reality checks such as the Hofstee method, P values and correlation analysis can improve validity. The Rasch model of student ability and item difficulty assists in modifying assessment questions, pinpointing areas for additional instruction. We propose 12 tips to support test developers in interpreting structured psychometric reports, including analysis and refinement of flawed items and ensuring fair assessments with accurate and defensible marks.

Increased pulse wave velocity is not associated with elevated augmentation index in patients with diabetes.

OBJECTIVE: Increased arterial stiffness is a risk factor for cardiovascular disease and is a feature associated with diabetes. Pulse wave velocity (PWV) is an accepted index of arterial stiffness and augmentation index (AI) derived from radial applanation tonometry has been advocated as a measurement of arterial stiffness. This study compares the relationship between PWV and AI in people with and without diabetes. DESIGN AND METHODS: A total of 66 people with diabetes and 66 age-matched non-diabetic controls were studied. Central aortic pressure waves were generated using applanation tonometry over the radial artery and used to calculate AI. Carotid-femoral PWV (PWVcf) was measured simultaneously. RESULTS: Relative to controls, diabetes was associated with increased pulse pressure (PP) and PWVcf (P < 0.01). In contrast, AI did not differ between groups even after adjustment for heart rate. This observation remained consistent irrespective of diabetes type, arterial site, and the presence or absence of antihypertensive therapy. Multiple regression analysis revealed diabetes to be a significant determinant of PWVcf, but not AI. CONCLUSIONS: PP and PWVcf are increased in people with diabetes, but this is not associated with increased AI. These findings conclusively demonstrate that AI is not a reliable measure of arterial stiffness in people with diabetes.

Stabilisation of coronary stents using rapid right ventricular pacing.

AIMS: Excessive movement of coronary stents within the artery can make precise stent placement difficult. This study assessed the use of rapid right ventricular pacing to reduce stent motion to improve the accuracy of placement. METHODS AND RESULTS: During percutaneous coronary intervention, if excessive stent movement prevented accurate stent placement, rapid right ventricular pacing was performed to reduce stent motion within the coronary artery during both stent positioning and deployment. Post procedural angiograms were analysed by two independent operators to measure stent movement during sinus rhythm and during rapid right ventricular pacing. Rapid right ventricular pacing was considered necessary in ten patients. No procedural complications occurred. Mean stent excursion for all patients in sinus rhythm was 2.9 mm (SD 1.6) and during rapid right ventricular pacing this was reduced to 0.8 mm (SD 0.6) (p<0.001). Movement assessed by individual operators ranged from 0.7 to 6.5 mm during sinus rhythm and from 0.1 to 2.4 mm during right ventricular pacing. CONCLUSIONS: Rapid right ventricular pacing is an effective and safe method to reduce stent movement and facilitate accurate stent deployment. This simple technique can be easily applied in any interventional cardiac catheterisation laboratory without the need for additional training or equipment.

Jittery, a Mutator distant relative with a paradoxical mobile behavior: excision without reinsertion.

The unstable mutation bz-m039 arose in a maize (Zea mays) stock that originated from a plant infected with barley stripe mosaic virus. The instability of the mutation is caused by a 3.9-kb mobile element that has been named Jittery (Jit). Jit has terminal inverted repeats (TIRs) of 181 bp, causes a 9-bp direct duplication of the target site, and appears to excise autonomously. It is predicted to encode a single 709-amino acid protein, JITA, which is distantly related to the MURA transposase protein of the Mutator system but is more closely related to the MURA protein of Mutator-like elements (MULEs) from Arabidopsis thaliana and rice (Oryza sativa). Like MULEs, Jit resembles Mutator in the length of the element's TIRs, the size of the target site duplication, and in the makeup of its transposase but differs from the autonomous element Mutator-Don Robertson in that it encodes a single protein. Jit also differs from Mutator elements in the high frequency with which it excises to produce germinal revertants and in its copy number in the maize genome: Jit-like TIRs are present at low copy number in all maize lines and teosinte accessions examined, and JITA sequences occur in only a few maize inbreds. However, Jit cannot be considered a bona fide transposon in its present host line because it does not leave footprints upon excision and does not reinsert in the genome. These unusual mobile element properties are discussed in light of the structure and gene organization of Jit and related elements.