Background and objectives: The COVID-19 pandemic has had an unprecedented reliance on informal caregivers as one of the pillars of healthcare systems. The aim of this study was to assess the quality of life of informal caregivers during the COVID-19 epidemic in Serbia. Materials and Methods: A cross-sectional study was conducted among informal caregivers during the COVID-19 epidemic in Serbia. Physical and mental quality of life was measured by the 36-Item Short-Form Health Survey. Additional data included sociodemographic characteristics, caregiver and care recipient characteristics, and COVID-19 related concerns. The qualitative component was performed using focus groups and individual in-depth interviews. Results: Out of 112 informal caregivers enrolled, most were female (80%), and the average age was 51.1 ± 12.3 years. The majority was delivering care to one person, who was a family member, on a daily basis (86.4%, 92%, and 91.1%, respectively). In multiple regression models, significant predictors of caregivers’ physical health were delivering care to a family member and a higher level of care complexity, while significant predictors of caregivers’ mental health were a higher level of care complexity and increased concerns about self-health and the health of the person being cared for due to the COVID-19 epidemic. Conclusions: Informal caregivers are experiencing negative physical and mental health outcomes during the COVID-19 epidemic in Serbia.

Citations are an important, but often overlooked, part of every scientific paper. They allow the reader to trace the flow of evidence, serving as a gateway to relevant literature. Most scientists are aware of citations errors, but few appreciate the prevalence of these problems. The purpose of this study was to examine how often frequently cited papers in biomedical scientific literature are cited inaccurately. The study included an active participation of first authors of included papers; to first-hand verify the citations accuracy. Findings from feasibility study, where we reviewed 1,540 articles containing 2,526 citations of 14 most cited articles in which the authors were affiliated with the Faculty of Medicine University of Belgrade, were further evaluated for external confirmation in an independent verification set of articles. Verification set included 4,912 citations identified in 2,995 articles that cited 13 most cited articles published by authors affiliated with the Mayo Clinic Division of Nephrology and Hypertension. A citation was defined as being accurate if the cited article supported or was in accordance with the statement by citing authors. At least one inaccurate citation was found in 11% and 15% of articles in the feasibility study and verification set, respectively, suggesting that inaccurate citations are common in biomedical literature. The most common problem was the citation of nonexistent findings (38.4%), followed by an incorrect interpretation of findings (15.4%). One fifth of inaccurate citations were due to chains of inaccurate citations. Based on these findings, several actions to reduce citation inaccuracies have been proposed.

Introduction: The analysis of cell-free DNA (cfDNA) for genetic abnormalities is a promising new approach for the diagnosis and prognosis of pancreatic cancer patients. Insights into the molecular characteristics of pancreatic cancer may provide valuable information, leading to its earlier detection and the development of targeted therapies. Material and Methods: We conducted a systematic review and a meta-analysis of studies that reported cfDNA in pancreatic ductal adenocarcinoma (PDAC). The studies were considered eligible if they included patients with PDAC, if they had blood tests for cfDNA/ctDNA, and if they analyzed the prognostic value of cfDNA/ctDNA for patients’ survival. The studies published before 22 October 2020 were identified through the PubMED, EMBASE, Web of Science and Cochrane Library databases. The assessed outcomes were the overall (OS) and progression-free survival (PFS), expressed as the log hazard ratio (HR) and standard error (SE). The summary of the HR effect size was estimated by pooling the individual trial results using the Review Manager, version 5.3, Cochrane Collaboration. The heterogeneity was assessed using the Cochran Q test and I2 statistic. Results: In total, 48 studies were included in the qualitative review, while 44 were assessed in the quantitative synthesis, with the total number of patients included being 3524. Overall negative impacts of cfDNA and KRAS mutations on OS and PFS in PDAC (HR = 2.42, 95% CI: 1.95–2.99 and HR = 2.46, 95% CI: 2.01–3.00, respectively) were found. The subgroup analysis of the locally advanced and metastatic disease presented similar results (HR = 2.51, 95% CI: 1.90–3.31). In the studies assessing the pre-treatment presence of KRAS, there was a moderate to high degree of heterogeneity (I2 = 87% and I2 = 48%, for OS and PFS, respectively), which was remarkably decreased in the analysis of the studies measuring post-treatment KRAS (I2 = 24% and I2 = 0%, for OS and PFS, respectively). The patients who were KRAS positive before but KRAS negative after treatment had a better prognosis than the persistently KRAS-positive patients (HR = 5.30, 95% CI: 1.02–27.63). Conclusion: The assessment of KRAS mutation by liquid biopsy can be considered as an additional tool for the estimation of the disease course and outcome in PDAC patients.