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Added value of FDG-PET for detection of progressive supranuclear palsy
Full text linkBackground : Diagnostic criteria for progressive supranuclear palsy (PSP) include midbrain atrophy in MRI and hypometabolism in [18F]fluorodeoxyglucose (FDG)-positron emission tomography (PET) as supportive features. Due to limited data regarding their relative and sequential value, there is no recommendation for an algorithm to combine both modalities to increase diagnostic accuracy. This study evaluated the added value of sequential imaging using state-of-the-art methods to analyse the images regarding PSP features. Methods : The retrospective study included 41 PSP patients, 21 with Richardson’s syndrome (PSP-RS), 20 with variant PSP phenotypes (vPSP) and 46 sex- and age-matched healthy controls. A pretrained support vector machine (SVM) for the classification of atrophy profiles from automatic MRI volumetry was used to analyse T1w-MRI (output: MRI-SVM-PSP score). Covariance pattern analysis was applied to compute the expression of a predefined PSP-related pattern in FDG-PET (output: PET-PSPRP expression score). Results : The area under the receiver operating characteristic curve for the detection of PSP did not differ between MRI-SVM-PSP and PET-PSPRP expression score (p≥0.63): about 0.90, 0.95 and 0.85 for detection of all PSP, PSP-RS and vPSP. The MRI-SVM-PSP score achieved about 13% higher specificity and about 15% lower sensitivity than the PET-PSPRP expression score. Decision tree models selected the MRI-SVM-PSP score for the first branching and the PET-PSPRP expression score for a second split of the subgroup with normal MRI-SVM-PSP score, both in the whole sample and when restricted to PSP-RS or vPSP. Conclusions : FDG-PET provides added value for PSP-suspected patients with normal/inconclusive T1w-MRI, regardless of PSP phenotype and the methods to analyse the images for PSP-typical features
A short history of Christianity beyond the West
Full text linkToday, the majority of the world's Christian population lives in the Global South. Knowledge of their history is therefore indispensable. This textbook offers a compact and vivid overview of the history of Christianity in Asia, Africa and Latin America since 1450, focussing on diversity and interdependence, local actors and global effects. Maps, illustrations and numerous photos as well as continuous references to easily accessible source texts support the reader's own reading and its use in various forms of academic teaching
Imaging endolymphatic space of the inner ear in vestibular migraine
Full text linkBackground: Vestibular migraine (VM), the most frequent episodic vertigo, is difficult to distinguish from Ménière’s disease (MD) because reliable biomarkers are missing. The classical proof of MD was an endolymphatic hydrops (EH). However, a few intravenous gadolinium-enhanced MRI studies of the inner ear (iMRI) also revealed an EH in VM. The major questions were the frequency and distribution characteristics of EH in VM for diagnostic use.
Methods: In a prospective case-control study of 200 participants, 75 patients with VM (49 females; mean age 46 years) and 75 with MD (36 females; mean age 55 years), according to the Bárány and International Headache Society, and 50 age-matched participants with normal vestibulocochlear testing (HP), were enrolled. Analyses of iMRI of the endolymphatic space included volumetric quantification, stepwise regression, correlation with neurotological parameters and support vector machine classification.
Results: EH was maximal in MD (80%), less in VM (32%) and minimal in HP (22%). EH was milder in VM (mean grade 0.3) compared with MD (mean grade 1.3). The intralabyrinthine distribution was preferably found in the vestibulum in VM, but mainly in the cochlea in MD. There was no interaural lateralisation of EH in VM but in the affected ear in MD. The grade of EH in the vestibulum was correlated in both conditions with the frequency and duration of the attacks.
Conclusion: Three features of the iMRI evaluation were most supportive for the diagnosis of VM at group and individual levels: (1) the bilateral manifestation, (2) the low-grade EH and (3) the intraaural distribution
Designing a Digital Flash Reading Test for Data-Based Decisions in Inclusive Classrooms: Duration and Word Length as Difficulty-Generating-Item Characteristics
Full text linkStandardized assessment tools are essential for informed, data-driven decision-making. Reading speedily is a crucial early skill that all students should have the opportunity to develop in inclusive classrooms. To facilitate classroom-based reading diagnostics in this area of reading, we developed a flash reading test that reliably measures the performance of students with and without learning disabilities and intellectual disabilities. This test can be administered in the classroom and completed independently by students, taking only a few minutes, without requiring them to read aloud. The test is designed to provide an accurate assessment of the speed of lexical recall for all students. To evaluate the difficulty-generating-item characteristics of the new instrument, 400 primary and special school students participated in the test. The results indicate that students with low abilities and disabilities are particularly differentiated by the combination of a short display duration and short words. We provide information for test developers interested in designing similar assessments and teachers who can use this instrument to make informed decisions in the classroom
Longitudinal analysis of anthropometric measures over 5 years in patients with Friedreich ataxia in the EFACTS natural history study
Full text linkGOLD grade-specific characterization of COPD in the COSYCONET multi-center trial: comparison of semiquantitative MRI and quantitative CT
Full text linkObjectives
We hypothesized that semiquantitative visual scoring of lung MRI is suitable for GOLD-grade specific characterization of parenchymal and airway disease in COPD and that MRI scores correlate with quantitative CT (QCT) and pulmonary function test (PFT) parameters.
Methods
Five hundred ninety-eight subjects from the COSYCONET study (median age = 67 (60–72)) at risk for COPD or with GOLD1-4 underwent PFT, same-day paired inspiratory/expiratory CT, and structural and contrast-enhanced MRI. QCT assessed total lung volume (TLV), emphysema, and air trapping by parametric response mapping (PRMEmph, PRMfSAD) and airway disease by wall percentage (WP). MRI was analyzed using a semiquantitative visual scoring system for parenchymal defects, perfusion defects, and airway abnormalities. Descriptive statistics, Spearman correlations, and ANOVA analyses were performed.
Results
TLV, PRMEmph, and MRI scores for parenchymal and perfusion defects were all higher with each GOLD grade, reflecting the extension of emphysema (all p < 0.001). Airway analysis showed the same trends with higher WP and higher MRI large airway disease scores in GOLD3 and lower WP and MRI scores in GOLD4 (p = 0.236 and p < 0.001). Regional heterogeneity was less evident on MRI, while PRMEmph and MRI perfusion defect scores were higher in the upper lobes, and WP and MRI large airway disease scores were higher in the lower lobes. MRI parenchymal and perfusion scores correlated moderately with PRMEmph (r = 0.61 and r = 0.60) and moderately with FEV1/FVC (r = −0.56).
Conclusion
Multi-center semiquantitative MRI assessments of parenchymal and airway disease in COPD matched GOLD grade-specific imaging features on QCT and detected regional disease heterogeneity. MRI parenchymal disease scores were correlated with QCT and lung function parameters
Exposure Profiles for the Long‐Term Use of Disinfectants and Cleaning Products and Asthma
Full text linkBackground:
Using disinfectants and cleaning products (DCPs) at home and work is known to influence both the onset and course of asthma, but most epidemiological studies did not consider the multiplicity and correlations of exposures to DCPs. We aimed to identify exposure profiles for the long-term weekly use of DCPs by latent class analysis (LCA) and assess their associations with asthma.
Methods:
LCA was conducted on data from 1143 young adults initially recruited in the German centers of Phase II of the International Study of Asthma and Allergies in Childhood (ISAAC) and followed up three times. In our LCA model, we included the use of cleaning sprays, disinfectant sprays, and nonspray disinfection methods, measured at ages 19–24 (first assessment) and 29–34 years (second assessment). Associations between identified exposure profiles and current as well as incident asthma/wheeze were evaluated by logistic regression.
Results:
We identified five long-term exposure profiles to DCPs (latent classes): no weekly use of DCPs (55% of participants), use in first assessment (7%), use in second assessment (18%), persistent use (8%), and persistent cleaning sprays use (12%). Compared to “no weekly use,” being in the “persistent use” profile was associated with both current asthma (OR = 1.68, 95% CI = [0.48–5.88]) and current wheeze (OR = 1.71, 95% CI = [0.75–3.90]). For incident asthma/wheeze, interval estimates were very wide.
Conclusions:
Our study identified five distinct long-term exposure profiles to DCPs. Among those, only a persistent weekly use of multiple DCPs over time seemed to have an adverse effect on asthma. However, large confidence intervals indicate considerable uncertainty
Ratio Bias Across Cultures and Disciplines: How Academic Background Shapes Statistical Decision‐Making
Full text linkRatios are an instrumental component of the communication of probabilities such as COVID incidence rates, side effects of medical drugs, or political decision-making; hence, they are a critical component of an individual's statistical decision-making. Research on the ratio bias has shown inconsistent results based on six major shortcomings which we surmount by replicating an identical experiment with students in Germany, Turkey, and Italy, with a physical, textual, and graphical depiction, and accounting for different levels of exposure to probabilities. In six studies (N = 1338), we show that lower exposure to probabilities leads to significantly more ratio bias–conform choices. The results also suggest that higher levels of statistical numeracy and risk literacy reduce ratio bias–conform choices. Our contribution helps to better understand the ratio bias concerning different populations and highlights different baselines for ratio bias–conform choices among subgroups in the population
Rational choices elicit stronger sense of agency in brain and behavior
Full text linkThe sense of agency is the subjective feeling of control over one's own actions and the associated outcomes. Here, we asked whether and to what extent the reasons behind our choices (operationalized by value differences, expected utility, and counterfactual option sets) drive our sense of agency. We simultaneously tested these three dimensions during a novel value-based decision-making task while recording explicit (self-reported) and implicit (brain signals) measures of agency. Our results show that choices that are more reasonable also come with a stronger sense of agency: humans report higher levels of control over the outcomes of their actions if (1) they were able to choose between different option values compared to randomly picking between options of identical value, (2) their choices maximizes utility (compared to otherwise) and yields higher than expected utility, and (3) they realize that they have not missed out on hidden opportunities. EEG results showed supporting evidence for factors (1) and (3): We found a higher P300 amplitude for picking than choosing and a higher Late-Positive Component when participants realized they had missed out on possible but hidden opportunities. Together, these results suggest that human agency is not only driven by the goal-directedness of our actions but also by their perceived rationality