On the Construct Validity of Stereotype Threat Measures: Some Possible Boundary Conditions

Since 1995, much research has focused on the negative effects that stereotype threat (ST) may have on task and test performance (e.g., Nguyen & Ryan, 2008). To date, however, no research has examined the underlying meaning of this construct in a manner precise enough to determine if it is indeed a unique and meaningful concept and any potential boundaries. Therefore, the main goal of the current research was to obtain a better understanding of what distinctions, if any, exist between ST and similar constructs. Using a factorial design and examining correlations among variables, measures of ST were compared to measures of three similar or related constructs: Stereotype Priming, Test Anxiety, and Test Motivation. In an attempt to clarify the meaning of both (1) these commonly used self-report measures, and (2) common experimental manipulations of those variables, a 3 (Blatant Stereotype Threat Cue vs. Implicit Stereotype Threat Cue vs. Stereotype Prime) x 2 (Well-Known Stereotype vs. Novel Stereotype) design was utilized. Significant differences between targets and non-targets of the ST were found for two of the dependent variables. A significant main effect for novelty of the stereotype and several significant interactions between novelty and cue type were found. More importantly, however, analyses of the qualitative data provided a better understanding of the ST phenomenon, its boundaries, and how it should be defined in the future. The potentials reasons for this effect and the limitation of the study are discussed

\u3ci\u3eIn Vitro\u3c/i\u3e Validation of Patient-Specific Hemodynamic Simulations in Coronary Aneurysms Caused by Kawasaki Disease

To perform experimental validation of computational fluid dynamics (CFD) applied to patient specific coronary aneurysm anatomy of Kawasaki disease. We quantified hemodynamics in a patient-specific coronary artery aneurysm physical phantom under physiologic rest and exercise flow conditions. Using phase contrast MRI (PCMRI), we acquired 3-component flow velocity at two slice locations in the aneurysms. We then performed numerical simulations with the same geometry and inflow conditions, and performed qualitative and quantitative comparisons of velocities between experimental measurements and simulation results. We observed excellent qualitative agreement in flow pattern features. The quantitative spatially and temporally varying differences in velocity between PCMRI and CFD were proportional to the flow velocity. As a result, the percent discrepancy between simulation and experiment was relatively constant regardless of flow velocity variations. Through 1D and 2D quantitative comparisons, we found a 5–17% difference between measured and simulated velocities. Additional analysis assessed wall shear stress differences between deformable and rigid wall simulations. This study demonstrated that CFD produced good qualitative and quantitative predictions of velocities in a realistic coronary aneurysm anatomy under physiological flow conditions. The results provide insights on factors that may influence the level of agreement, and a set of in vitro experimental data that can be used by others to compare against CFD simulation results. The findings of this study increase confidence in the use of CFD for investigating hemodynamics in the specialized anatomy of coronary aneurysms. This provides a basis for future hemodynamics studies in patient-specific models of Kawasaki disease

Researchers' experiences of the design and conduct challenges associated with parallel-group cluster-randomised trials and views on a novel open-cohort design

BACKGROUND: Two accepted designs exist for parallel-group cluster-randomised trials (CRTs). Closed-cohort designs follow the same individuals over time with a single recruitment period before randomisation, but face challenges in settings with high attrition. (Repeated) cross-sectional designs recruit at one or more timepoints before and/or after randomisation, collecting data from different individuals present in the cluster at these timepoints, but are unsuitable for assessment of individual change over time. An 'open-cohort' design allows individual follow-up with recruitment before and after cluster-randomisation, but little literature exists on acceptability to inform their use in CRTs. AIM: To document the views and experiences of expert trialists to identify: a) Design and conduct challenges with established parallel-group CRT designs,b) Perceptions of potential benefits and barriers to implementation of open-cohort CRTs,c) Methods for minimising, and investigating the impact of, bias in open-cohort CRTs. METHODS: Qualitative consultation via two expert workshops including triallists (n = 24) who had worked on CRTs over a range of settings. Workshop transcripts were analysed using Descriptive Thematic Analysis utilising inductive and deductive coding. RESULTS: Two central organising concepts were developed. Design and conduct challenges with established CRT designs confirmed that current CRT designs are unable to deal with many of the complex research and intervention circumstances found in some trial settings (e.g. care homes). Perceptions of potential benefits and barriers of open cohort designs included themes on: approaches to recruitment; data collection; analysis; minimising/investigating the impact of bias; and how open-cohort designs might address or present CRT design challenges. Open-cohort designs were felt to provide a solution for some of the challenges current CRT designs present in some settings. CONCLUSIONS: Open-cohort CRT designs hold promise for addressing the challenges associated with standard CRT designs. Research is needed to provide clarity around definition and guidance on application.</p

Interpreting Quality of Life after Brain Injury (QOLIBRI) scores: Cross-walk with the Short Form-36

The Quality of Life after Brain Injury (QOLIBRI) instruments are traumatic brain injury-specific assessments of health-related quality of life (HRQoL), with established validity and reliability. The purpose of the study is to help improve the interpretability of the two QOLIBRI summary scores (the QOLIBRI Total score and the QOLBRI Overall Scale score). An analysis was conducted of 761 patients with traumatic brain injury (TBI) that took part in the QOLIBRI validation studies. A cross-walk between QOLIBRI scores and the SF-36 Mental Component Summary norm-based scoring system was performed using geometric mean regression analysis. The exercise supports a previous suggestion that QOLIBRI Total scores &lt; 60 indicate low or impaired HRQoL, and indicate that the corresponding score on the QOLIBRI-OS is &lt;52. The percentage of cases in the sample that fell into the &lsquo;impaired HRQoL&rsquo; category were 36% for the Mental Component Summary, 38% for the QOLIBRI Total, and 39% for the QOLIBRI-OS. Relationships between the QOLIBRI scales and the Glasgow Outcome Scale &ndash; Extended (GOSE), as a measure of global function, are presented in the form of means and standard deviations that allow comparison with other studies, and data on age and gender are presented for the QOLIBRI-OS. While bearing in mind the potential imprecision of the comparison, the findings provide a framework for evaluating QOLIBRI summary scores in relation to generic HRQoL that improves their interpretability

Clinically Valuable Quality Control for PET/MRI Systems:Consensus Recommendation From the HYBRID Consortium

International audienceQuality control (QC) of medical imaging devices is essential to ensure their proper function and to gain accurate and quantitative results. Therefore, several international bodies have published QC guidelines and recommendations for a wide range of imaging modalities to ensure adequate performance of the systems. Hybrid imaging systems such as positron emission tomography/computed tomography (PET/CT) or PET/magnetic resonance imaging (PET/MRI), in particular, present additional challenges caused by differences between the combined modalities. However, despite the increasing use of this hybrid imaging modality in recent years, there are no dedicated QC recommendations for PET/MRI. Therefore, this work aims at collecting information on QC procedures across a European PET/MRI network, presenting quality assurance procedures implemented by PET/MRI vendors and achieving a consensus on PET/MRI QC procedures across imaging centers. Users of PET/MRI systems at partner sites involved in the HYBRID consortium were surveyed about local frequencies of QC procedures for PET/MRI. Although all sites indicated that they perform vendor-specific daily QC procedures, significant variations across the centers were observed for other QC tests and testing frequencies. Likewise, variations in available recommendations and guidelines and the QC procedures implemented by vendors were found. Based on the available information and our clinical expertise within this consortium, we were able to propose a minimum set of PET/MRI QC recommendations including the daily QC, cross-calibration tests, and an image quality (IQ) assessment for PET and coil checks and MR image quality tests for MRI. Together with regular checks of the PET-MRI alignment, proper PET/MRI performance can be ensured

Anti-interleukin-13 and anti-interleukin-4 agents versus placebo, anti-interleukin-5 or anti-immunoglobulin-E agents, for children and adults with asthma

This is a protocol for a Cochrane Review (Intervention). The objectives are as follows: To assess the efficacy and safety of anti-interleukin-13 or anti-interleukin-4 agents, compared with placebo, anti-Immunoglobulin E agents, or anti-interleukin-5 agents, for the treatment of children, adolescents, or adults with asthma