Systematic review

A systematic review is a type of literature review that collects and critically analyzes multiple research studies or papers. A review of existing studies is often quicker and cheaper than embarking on a new study. Researchers use methods that are selected before one or more research questions are formulated, and then they aim to find and analyze studies that relate to and answer those questions. Systematic reviews of randomized controlled trials are key in the practice of evidence-based medicine.

An understanding of systematic reviews, and how to implement them in practice, is highly recommended for professionals involved in the delivery of health care. Besides health interventions, systematic reviews may examine clinical tests, public health interventions, environmental interventions, social interventions, adverse effects, and economic evaluations. Systematic reviews are not limited to medicine and are quite common in all other sciences where data are collected, published in the literature, and an assessment of methodological quality for a precisely defined subject would be helpful.

A systematic review aims to provide a complete, exhaustive summary of current literature relevant to a research question. The first step in conducting a systematic review is to perform a thorough search of the literature for relevant papers. The Methodology section of a systematic review will list all of the databases and citation indexes that were searched such as Web of Science, Embase, and PubMed and any individual journals that were searched. The titles and abstracts of identified articles are checked against pre-determined criteria for eligibility and relevance to form an inclusion set. This set will relate back to the research problem. Each included study may be assigned an objective assessment of methodological quality preferably by using methods conforming to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement (the current guideline) or the high quality standards of Cochrane collaboration.

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