Systematic reviews should incorporate as much relevant evidence as possible to reduce
bias and research waste and increase reliability of results. Clinical trials registers are a key …

Objective To evaluate the impact of searching clinical trial registries in systematic reviews.
Design Methodological systematic review and reanalyses of meta-analyses. Data sources …

Background: Since 2005, International Committee of Medical Journal Editors (ICMJE)
member journals have required that clinical trials be registered in publicly available trials …

Preparing a review entails many judgments. The focus of the review must be decided.
Studies that are relevant to the focus of the review must be identified, selected for inclusion …

Background Publication bias is a major threat to the validity of systematic reviews. Searches
of clinical trials registries can help to identify unpublished trials, though little is known about …

Background It is generally believed that exhaustive searches of bibliographic databases are
needed for systematic reviews of health care interventions. The CENTRAL database of …

Updating of systematic reviews is generally more efficient than starting all over again when
new evidence emerges, but to date there has been no clear guidance on how to do this. This …

One of the key elements in evidence-based medicine (EBM) is reliable information from
research on the benefits and harms of specific interventions, actions or strategies. This is …

Abstract The Cochrane Collaboration was established in 1993, following the opening of the
UK Cochrane Centre in 1992, at a time when searching for studies for inclusion in …

Objective: To develop optimal search strategies in Medline for retrieving systematic reviews.
Design: Analytical survey. Data sources: 161 journals published in 2000 indexed in Medline …