Comparison of the English and French versions of the CASPer® Test in a bilingual population.

This article was migrated. The article was marked as recommended. Objective The University of Ottawa MD program has two different streams to which candidates may apply: a francophone stream and an anglophone stream. As the admissions office receives applications in both French and English, they are required to ensure that the tools used to assess candidates are psychometrically equivalent across both streams. CASPer is a standardized test they recently adopted to assess the non-cognitive competencies of applicants and is offered in both English and French. The objective of this study is to compare the psychometric properties of the English and French versions of CASPer. Methods We collected data from all CASPer test-takers across three cohorts (n = 12,463; entry 2016, entry 2017, entry 2018). We first compared the difficulty of the test between the French and English version using proxy indicators (i.e., time to completion, typing speed). We then compared the psychometric properties of the two versions based on their internal-consistency reliability and applicant acceptability. Results There were some indications that the French version may be slightly more difficult than the English version of the CASPer test. However, it is unclear whether this difficulty is due to the difficulty of the individual test items or to differences in the characteristics of the cohort. Nevertheless, a comparison of the psychometric indicators suggests that both French and English versions of CASPer are psychometrically sound and equivalent. Conclusion Although CASPer scores cannot be directly compared between the English and French versions, the psychometric properties of the assessment were retained across the two versions. These results provide preliminary evidence that the psychometric strengths of the English version of CASPer likely extend to the French version of the assessment.

Calibrating the X-ray attenuation of liquid water and correcting sample movement artefacts during in operando synchrotron X-ray radiographic imaging of polymer electrolyte membrane fuel cells.

Synchrotron X-ray radiography, due to its high temporal and spatial resolutions, provides a valuable means for understanding the in operando water transport behaviour in polymer electrolyte membrane fuel cells. The purpose of this study is to address the specific artefact of imaging sample movement, which poses a significant challenge to synchrotron-based imaging for fuel cell diagnostics. Specifically, the impact of the micrometer-scale movement of the sample was determined, and a correction methodology was developed. At a photon energy level of 20 keV, a maximum movement of 7.5 µm resulted in a false water thickness of 0.93 cm (9% higher than the maximum amount of water that the experimental apparatus could physically contain). This artefact was corrected by image translations based on the relationship between the false water thickness value and the distance moved by the sample. The implementation of this correction method led to a significant reduction in false water thickness (to ∼0.04 cm). Furthermore, to account for inaccuracies in pixel intensities due to the scattering effect and higher harmonics, a calibration technique was introduced for the liquid water X-ray attenuation coefficient, which was found to be 0.657 ± 0.023 cm(-1) at 20 keV. The work presented in this paper provides valuable tools for artefact compensation and accuracy improvements for dynamic synchrotron X-ray imaging of fuel cells.