The aim of the article was to identify and summarize studies assessing methodologies for study selection, data abstraction, or quality appraisal in systematic reviews.

It has been suggested that some placebo interventions might be associated with larger clinical effects than others. In a systematic review, we investigated whether there is evidence from direct comparisons in randomized clinical trials including two or more placebo groups supporting this hypothesis.

To explore the outcome domains and measurement instruments reported in published randomized controlled trials of physical therapy interventions for shoulder pain (rotator cuff disease, adhesive capsulitis, or nonspecific shoulder pain).

To collate and categorize the ways in which selective inclusion and reporting can occur in randomized controlled trials (RCTs) and systematic reviews.

To estimate the frequency of data and code availability statements in a random sample of systematic reviews with meta-analysis of aggregate data, summarize the content of the statements and investigate how often data and code files were shared.

To investigate how often review authors encounter multiple results from included studies that are eligible for inclusion in a particular meta-analysis, and how often methods to select results are specified.

The Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) statement, published in 2009, was designed to help systematic reviewers transparently report why the review was done, what the authors did, and what they found. Over the past decade, advances in systematic review methodology and terminology have necessitated an update to the guideline. The PRISMA 2020 statement replaces the 2009 statement and includes new reporting guidance that reflects advances in methods to identify, select, appraise, and synthesise studies. The structure and presentation of the items have been modified to facilitate implementation. In this article, we present the PRISMA 2020 27-item checklist, an expanded checklist that details reporting recommendations for each item, the PRISMA 2020 abstract checklist, and the revised flow diagrams for original and updated reviews.

To investigate the association between methodological quality and reported conclusions of meta-analyses comparing operative with non-operative treatments for proximal humerus fractures.

The minimum clinically important difference (MCID) is used to interpret the relevance of treatment effects, e.g., when developing clinical guidelines, evaluating trial results or planning sample sizes. There is currently no agreement on an appropriate MCID in chronic pain and little is known about which contextual factors cause variation.

To evaluate how often reproducible research practices, which allow others to recreate the findings of studies, given the original data, are used in systematic reviews (SRs) of biomedical research.

To investigate the completeness and currency of published systematic reviews of remdesivir for COVID-19 and to compare this with a living guidelines approach.