382,714 papers found

Random-effects meta-analysis is a widely applied methodology to synthesize research findings of studies related to a specific scientific question. Besides estimating the mean effect, an important aim of the meta-analysis is to summarize the heterogeneity, that is, the variation in the underlying effects caused by the d…

A random-effects meta-analysis by Glantz et al. recently concluded that the odds of several diseases among current e-cigarette users and smokers were similar. This report details serious deficiencies. We used descriptive analysis methods to assess the studies the authors selected for cardiovascular disease (CVD), strok…

Meta-analyses, which present the best source of information on the effectiveness of interventions, are influenced by several biases. One category relates to the convenience of selective inclusion of those primary studies, which are more easily available than others. This availability bias includes bias from excluding t…

This study aims to provide evidence regarding whether Qingufei paidu decoction (, QFPD) treatment in the acute phase shows long-term benefits for coronavirus disease 2019-associated sequelae. The 10 databases will be retrieved. Every reference list of related trials and gray literature will be searched as well. Study s…

There is a deficit between existing levels of paediatric clinical research in low- and middle-income countries (LMICs) and what is warranted based on the disease burden in children in these countries. Lack of market protections, low ability to pay and cost-based pricing are key commercial barriers to industry-funded pa…

The relationship between the treatment effect and the baseline risk is a recognized tool to investigate the heterogeneity of treatment effects in meta-analyses of clinical trials. Since the baseline risk is difficult to measure, a proxy is adopted, which is based on the rate of events for the subject under the control…

BACKGROUND: Several studies have documented that specific Indigenous groups have been disproportionately affected by previous pandemics. The objective of this paper is to describe the protocol to be used in a review and meta-analysis of the literature on Indigenous groups and influenza. Using this protocol as a guide,…

Reference intervals, or reference ranges, aid medical decision-making by containing a pre-specified proportion (e.g., 95%) of the measurements in a representative healthy population. We recently proposed three approaches for estimating a reference interval from a meta-analysis based on a random effects model: a frequen…

With great interest, we have read the recent article "The risk of malignancy in patients with IgG4-related disease: a systematic review and meta-analysis" by Yu et al. While we have a great appreciation for the work conducted by the authors there are some methodological issues need to be considered. First, the period o…

One of the key features of network meta-analysis is ranking of interventions according to outcomes of interest. Ranking metrics are prone to misinterpretation because of two limitations associated with the current ranking methods. First, differences in relative treatment effects might not be clinically important and th…

Mendelian randomization (MR) uses genetic variants as instrumental variables to infer whether a risk factor causally affects a health outcome. Meta-analysis has been used historically in MR to combine results from separate epidemiological studies, with each study using a small but select group of genetic variants. In r…

An aggregate data meta-analysis is a statistical method that pools the summary statistics of several selected studies to estimate the outcome of interest. When considering a continuous outcome, typically each study must report the same measure of the outcome variable and its spread (eg, the sample mean and its standard…

We have developed a method, called Meta-STEPP (subpopulation treatment effect pattern plot for meta-analysis), to explore treatment effect heterogeneity across covariate values in the meta-analysis setting for time-to-event data when the covariate of interest is continuous. Meta-STEPP forms overlapping subpopulations f…

This paper proposes a new method to evaluate informative hypotheses for meta-analysis of Cronbach's coefficient alpha using a Bayesian approach. The coefficient alpha is one of the most widely used reliability indices. In meta-analyses of reliability, researchers typically form specific informative hypotheses beforehan…

This article examines an improved alternative to the random effects (RE) model for meta-analysis of heterogeneous studies. It is shown that the known issues of underestimation of the statistical error and spuriously overconfident estimates with the RE model can be resolved by the use of an estimator under the fixed eff…

Systematic reviews and meta-analyses have long been fundamental tools for evidence-based clinical practice. Initially, meta-analyses were proposed as a technique that could improve the accuracy and the statistical power of previous research from individual studies with small sample size. However, one of its main limita…

Dose-response studies are performed to investigate the potency of a compound. EC50 is the concentration of the compound that gives half-maximal response. Dose-response data are typically evaluated by using a log-logistic model that includes EC50 as one of the model parameters. Often, more than one experiment is carried…

OBJECTIVES: To collect reasons for selecting the methods for meta-analysis of diagnostic accuracy from authors of systematic reviews and improve guidance on recommended methods. STUDY DESIGN AND SETTING: Online survey in authors of recently published meta-analyses of diagnostic accuracy. RESULTS: We identified 100 el…

In this article, we present an overview and tutorial of statistical methods for meta-analysis of diagnostic tests under two scenarios: (1) when the reference test can be considered a gold standard and (2) when the reference test cannot be considered a gold standard. In the first scenario, we first review the convention…

INTRODUCTION: Emerging studies have compared the analgesic effects of quadratus lumborum block versus caudal block in paediatric surgeries, but the results remain controversial. This protocol of a systematic review and meta-analysis aims to determine whether quadratus lumborum block is better than caudal block for post…