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Systematic Review Guide


What is a systematic review? 

A Systematic review “attempts to collate all empirical evidence that fits pre-specified eligibility criteria in order to answer a specific research question.  It uses explicit, systematic methods that are selected with a view to minimizing bias, thus providing more reliable findings from which conclusions can be drawn and decisions made.

How long does it take to complete a systematic review?

The entire process--from creating a research question, through conducting the literature search, screening results, analyzing data, and writing a manuscript can take as long as 18 months. We can usually complete the literature search for the systematic review within 4-6 weeks. 

Does Becker Library charge any fees for the systematic review service?

Our systematic review service is available for free to all Washington University faculty, staff, and students, and to faculty/staff at Barnes Jewish Hospital and St. Louis Children's Hospital. Please note, however, that you may need to budget money for interlibrary loan (for materials Becker Library doesn't own), or to purchase software. 

Am I expected to include my collaborating librarian as an author on a published systematic review?

The amount of work your collaborating librarian completes for the systematic review typically meets the ICJME criteria for authorship (for more info, see the Becker SR Service tab). We ask that you do not include your collaborating librarian's search methods or search strategies in a published manuscript unless they are included as an author. 

Why is my collaborating librarian including so many databases in the search? 

The goal of a systematic review search is to find all available evidence for your research topic. This means putting together a detailed, thorough search strategy. It also means searching multiple database resources. There is no single database that indexes all journals (not even Google Scholar), so it is necessary to search more than one. You can discuss the databases that will be searched (and recommend those you would like to include) when you consult with your collaborating librarian. 

How many articles are typically retrieved in a systematic review search?

The number of articles retrieved depends on how narrowly/widely focused the research question is, the novelty of the topic, and other factors. It is not unusual to receive a few hundred results for a narrowly-focused question, or a few thousand results for a broader question. It is important to keep in mind that you will very likely receive far more results than a typical literature search.  Early in the planning process for your systematic review you should carefully consider the time commitment that will be necessary for screening a potentially large number of results.

Why is my collaborating librarian including search results for clinical trials or other grey literature resources? 

Systematic review guidelines encourage researchers to include information from grey literature resources in their analysis. Unpublished data from grey literature resources may have a significant impact on the conclusions of your systematic review. Using grey literature also decreases the potential for publication bias.

Will my collaborating librarian retrieve full text articles for my SR project?

Full text article retrieval is not part of our systematic review service. However, if you run into problems with accessing full text or have any questions we are happy to help. Your collaborating librarian can assist you with questions or concerns.