Publications by authors named "A Zapf"

Background: To intraindividually compare the diagnostic performance of positron emission computed tomography (F-18-FDG-PET/CT) and diffusion-weighted magnetic resonance imaging (DW-MRI) in a non-inferiority design for the discrimination of peripheral nerve sheath tumours as benign (BPNST), atypical (ANF), or malignant (MPNST) in patients with neurofibromatosis type 1 (NF1).

Results: In this prospective single-centre study, thirty-four NF1 patients (18 male; 30 ± 11 years) underwent F-18-FDG-PET/CT and multi-b-value DW-MRI (11 b-values 0 - 800 s/mm²) at 3T. Sixty-six lesions corresponding to 39 BPNST, 11 ANF, and 16 MPNST were evaluated.

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Evaluating diagnostic test accuracy during epidemics is difficult due to an urgent need for test availability, changing disease prevalence and pathogen characteristics, and constantly evolving testing aims and applications. Based on lessons learned during the SARS-CoV-2 pandemic, we introduce a framework for rapid diagnostic test development, evaluation, and validation during outbreaks of emerging infections. The framework is based on the feedback loop between test accuracy evaluation, modelling studies for public health decision-making, and impact of public health interventions.

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Background: Transgender and gender diverse (TGD) people in remote areas face challenges accessing health-care services, including mental health care and gender-affirming medical treatment, which can be associated with psychological distress. In this study, we aimed to evaluate the effectiveness of a 4-month TGD-informed e-health intervention to improve psychological distress among TGD people from remote areas in northern Germany.

Methods: In a randomised controlled trial done at a single centre in Germany, adults (aged ≥18 years) who met criteria for gender incongruence or gender dysphoria and who lived at least 50 km outside of Hamburg in one of the northern German federal states were recruited and randomly assigned (1:1) to iTransHealth intervention or a wait list control group.

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Article Synopsis
  • The field of meta-analysis for diagnostic test accuracy studies is evolving, focusing on methods to analyze multiple thresholds of sensitivity and specificity.
  • A case study highlighted the application of various methods for meta-analyzing diagnostic test studies, but no comprehensive simulation has compared these methods systematically.
  • This article presents a simulation study that evaluates three frequentist approaches for analyzing ROC curves, finding that Hoyer et al.'s method performed the best in most scenarios and is suggested for practical use.
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Background And Aims: The optimal antithrombotic therapy in patients with device-detected atrial fibrillation (DDAF) is unknown. Concomitant vascular disease can modify the benefits and risks of anticoagulation.

Methods: These pre-specified analyses of the NOAH-AFNET 6 (n = 2534 patients) and ARTESiA (n = 4012 patients) trials compared anticoagulation with no anticoagulation in patients with DDAF with or without vascular disease, defined as prior stroke/transient ischaemic attack, coronary or peripheral artery disease.

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