Systematic reviews

Overview of systematic review steps and resources to assist researchers conducting reviews.

Identifying existing systematic reviews

One of the first and most important steps of the systematic review process is to ask yourself 'Has anyone done this before, or is anyone currently working on it?'. Systematic review registration sites will help you find published reviews and those that are currently in progress.

Searching registration sites and registering your protocol

Making protocols publicly available increases transparency and can reduce duplication of effort. In some cases journal publishers may refuse to publish systematic reviews that aren't already registered before their completion. Note: Systematic reviews need to be at the protocol stage before being registered.

The following registration sites and systematic review databases can be searched to identify registered systematic review protocols, and published systematic reviews. Begin by searching for your topic in some of the following.

Campbell Collaboration This link opens in a new window
The Campbell Collaboration collaborates closely with its sibling organization, the Cochrane Collaboration. Disciplines: education, criminal justice and social welfare.
Cochrane Library This link opens in a new window
Collection of databases in medicine and other healthcare specialities provided by Cochrane. At its core is the collection of Cochrane Reviews, a database of systematic reviews and meta-analyses which summarize and interpret the results of medical research.

Cochrane Reviews
Proposing and registering new Cochrane Reviews.
Discipline: Health care
Collaboration for Environmental Evidence
CEE seeks to promote and deliver evidence syntheses on issues of greatest concern to environmental policy and practice as a public service.
Discipline: Environmental issues
Database of Abstracts of Reviews of Effects (DARE)
Joanna Briggs Institute Systematic Review Register
This is a list of registered systematic reviews that are currently under way.
Discipline: Health care
Open Science Framework
OSF provides a place to register review protocols. Designed to be applicable across disciplines (i.e., psychology, economics, law, physics, or any other field) and across review types (i.e., scoping review, review of qualitative studies, meta-analysis, or any other type of review). For non-health reviews, create a free account then add a new registry item and select the ‘Generalized Systematic Review Registration’ form.
PROSPERO
An international database of prospectively registered systematic reviews in health and social care (no Scoping Reviews). Disciplines: Health and Social Care, Welfare, Public Health, Education, Crime, Justice, and International Development
PROSPERO: Registration guidance
Guidance notes for registering a systematic review protocol with PROSPERO
Research Registry
Offers registration for all types of research studies, including case reports, observational/interventional studies, systematic reviews and meta-analyses.
Systematic Reviews
This journal publishes high quality systematic review products including systematic review protocols.

Finding systematic reviews in other databases

The best way to find systematic reviews in databases is by using peer reviewed study-type filters which can be added to your search strategy as an additional search string (combined with AND).

Some databases include filtering or limiting options to identify systematic reviews and meta analyses, however their use is generally not recommended for systematic searching, and should be used with caution. They will save time but there is a risk that relevant articles will be missed. This is because many studies, especially recent studies, may not yet have been indexed or correctly indexed by the database, so non-indexed articles will not be retrieved when using the limit.

Ovid Embase

Ovid Embase has a search filter that will pick up systematic reviews and meta-analyses. Use the link below to learn about the filter:

Embase systematic review & meta-analysis filter
This filter is one of several Embase filters provided by Ovid on their Expert Searches page.

PubMed

It is safe to use the PubMed built-in Systematic Review filter as it uses a combination of keywords and publication type. However, the Meta-analysis filter in PubMed only uses publication type, so should be supplemented with additional keywords. The following search string will cover both systematic reviews and meta-analyses and can be combined with the rest of your PubMed search using AND.

Systematic review[sb] OR metaanalys*[all] OR meta analys*[all] OR meta-analysis[pt]

PubMed 'article type' filters
Learn more about ‘article type’ filters in PubMed, and view the full ‘systematic review’ filter search strategy.

Ovid Medline

To locate systematic reviews in Ovid Medline:

Run your topic search/es
Run the following meta-analysis search string: meta analysis.pt. or metaanalys*.mp. or meta analys*.mp.
In your Search History, combine the final topic search with the meta-analysis keyword searching using AND. This will create a search labelled 1 and 2 in your Search History
Select Display results for the final topic search (before the meta-analysis search) - in the image below, search 1
Select Additional limits
Navigate to the Subject Subsets
Select Systematic Reviews to apply the filter to your final topic search
Finally, combine your Systematic review filtered search with your Meta-analysis filtered search using OR

Your Search History should look like this: