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Objectives COVID-19, since its emergence in December 2019, has globally impacted research. Over 360 000 COVID-19-related manuscripts have been published on PubMed and preprint servers like medRxiv and bioRxiv, with preprints comprising about 15% of all manuscripts. Yet, the role and impact of preprints on COVID-19 research and evidence synthesis remain uncertain. Materials and Methods We propose a novel data-driven method for assigning weights to individual preprints in systematic reviews and meta-analyses. This weight termed the "confidence score" is obtained using the survival cure model, also known as the survival mixture model, which takes into account the time elapsed between posting and publication of a preprint, as well as metadata such as the number of first 2-week citations, sample size, and study type. Results Using 146 preprints on COVID-19 therapeutics posted from the beginning of the pandemic through April 30, 2021, we validated the confidence scores, showing an area under the curve of 0.95 (95% CI, 0.92-0.98). Through a use case on the effectiveness of hydroxychloroquine, we demonstrated how these scores can be incorporated practically into meta-analyses to properly weigh preprints. Discussion It is important to note that our method does not aim to replace existing measures of study quality but rather serves as a supplementary measure that overcomes some limitations of current approaches. Conclusion Our proposed confidence score has the potential to improve systematic reviews of evidence related to COVID-19 and other clinical conditions by providing a data-driven approach to including unpublished manuscripts. [ABSTRACT FROM AUTHOR]

Prediction modeling for clinical decision making is of great importance and needed to be updated frequently with the changes of patient population and clinical practice. Existing methods are either done in an ad hoc fashion, such as model recalibration or focus on studying the relationship between predictors and outcome and less so for the purpose of prediction. In this article, we propose a dynamic logistic state space model to continuously update the parameters whenever new information becomes available. The proposed model allows for both time‐varying and time‐invariant coefficients. The varying coefficients are modeled using smoothing splines to account for their smooth trends over time. The smoothing parameters are objectively chosen by maximum likelihood. The model is updated using batch data accumulated at prespecified time intervals, which allows for better approximation of the underlying binomial density function. In the simulation, we show that the new model has significantly higher prediction accuracy compared to existing methods. We apply the method to predict 1 year survival after lung transplantation using the United Network for Organ Sharing data. [ABSTRACT FROM AUTHOR]

Small study effects occur when smaller studies show different, often larger, treatment effects than large ones, which may threaten the validity of systematic reviews and meta‐analyses. The most well‐known reasons for small study effects include publication bias, outcome reporting bias, and clinical heterogeneity. Methods to account for small study effects in univariate meta‐analysis have been extensively studied. However, detecting small study effects in a multivariate meta‐analysis setting remains an untouched research area. One of the complications is that different types of selection processes can be involved in the reporting of multivariate outcomes. For example, some studies may be completely unpublished while others may selectively report multiple outcomes. In this paper, we propose a score test as an overall test of small study effects in multivariate meta‐analysis. Two detailed case studies are given to demonstrate the advantage of the proposed test over various naive applications of univariate tests in practice. Through simulation studies, the proposed test is found to retain nominal Type I error rates with considerable power in moderate sample size settings. Finally, we also evaluate the concordance between the proposed tests with the naive application of univariate tests by evaluating 44 systematic reviews with multiple outcomes from the Cochrane Database. [ABSTRACT FROM AUTHOR]

Funnel plots have been widely used to detect small-study effects in the results of univariate meta-analyses. However, there is no existing visualization tool that is the counterpart of the funnel plot in the multivariate setting. We propose a new visualization method, the galaxy plot, which can simultaneously present the effect sizes of bivariate outcomes and their standard errors in a 2-dimensional space. We illustrate the use of the galaxy plot with 2 case studies, including a meta-analysis of hypertension trials with studies from 1979–1991 (Hypertension. 2005;45(5):907–913) and a meta-analysis of structured telephone support or noninvasive telemonitoring with studies from 1966–2015 (Heart. 2017;103(4):255–257). The galaxy plot is an intuitive visualization tool that can aid in interpreting results of multivariate meta-analysis. It preserves all of the information presented by separate funnel plots for each outcome while elucidating more complex features that may only be revealed by examining the joint distribution of the bivariate outcomes. [ABSTRACT FROM AUTHOR]

The article discusses various reports published within the issue which includes elements of palliative care, importance of deactivating implantable cardioverter defibrillators and palliative care needs of individuals of all ages, independent of diagnosis and living circumstances.

Aims To evaluate outcomes for left main coronary artery (LMCA) stenting and compare results between protected (left coronary grafted) and unprotected LMCA stenting in the current bare-metal stent era.Methods We reviewed outcomes among 142 consecutive patients who underwent protected or unprotected LMCA stenting since 1997. All-cause mortality, myocardial infarction (MI), target-lesion revascularization (TLR), and the combined majoradverse clinical event (MACE) rates at one year were computed.Results Ninety-nine patients (70%) underwent protected and 43 patients (30%) underwent unprotected LMCA stenting. In the unprotected group, 86% were considered poor surgical candidates. Survival at one year was 88% for all patients, TLR 20%, and MACE 32%. At one year, survival was reduced in the unprotected group (72% vs. 95%, P<0.001) and MACE was increased in the unprotected patients (49% vs. 25%, P=0.005).Conclusions In the current era, stenting for both protected and unprotected LMCA disease is still associated with high long-term mortality and MACE rates. Stenting for unprotected LMCA disease in a high-risk population should only be considered in the absence of other revascularization options. Further studies are needed to evaluate the role of stenting for unprotected LMCA disease. [ABSTRACT FROM PUBLISHER]

Background. Erectile dysfunction (ED) may be one manifestation of a generalized vascular disorder characterized by endothelial dysfunction. Statin drugs may improve endothelial function, even before altering the lipid profile. Objective. We sought to determine whether the addition of a statin with sildenafil would improve ED in men who initially responded poorly to sildenafil. Methods. Men with moderate-to-severe ED despite an adequate sildenafil trial were enrolled in this randomized, double-blind, placebo-controlled pilot study. ED was defined using a validated self-administered questionnaire as a score of ≤16 on the International Index of Erectile Function (erectile function domain score range of 6–30). Improvement in ED score with sildenafil was reassessed at 6 and 12 weeks of treatment with atorvastatin (80 mg daily) or matching placebo. Results. Twelve men (mean age 58 ± 13 years) with a mean domain score of 8.2 ± 6.9 and a mean duration of ED of 3.7 years were enrolled in the study. Treatment with atorvastatin decreased mean low-density lipoprotein cholesterol by 43% and resulted in an improvement with sildenafil in domain score of 7.8 ( P = 0.036); an effect was apparent by 6 weeks. The increase in domain score in placebo patients was not statistically significant. Conclusions. Treatment with atorvastatin improved sexual function and the response to oral sildenafil in men who did not initially respond to treatment with sildenafil. The results of this pilot study support the hypothesis that vascular endothelial dysfunction contributes to ED in sildenafil nonresponders and deserves further testing in a large clinical trial. Herrmann HC, Levine LA, Macaluso J Jr, Walsh M, Bradbury D, Schwartz S, Mohler ER III, and Kimmel SE. Can atorvastatin improve the response to sildenafil in men with erectile dysfunction not initially responsive to sildenafil? Hypothesis and pilot trial results. J Sex Med 2006;3:303–308. [ABSTRACT FROM AUTHOR]