Systematic Reviews

Why is it important to have a plan?

It is important to develop a review plan or protocol* to determine the inclusion and exclusion criteria to use. 

The benefits of having a protocol before the beginning of a review:

• relate to the validity and merit of a research process that reduces risk of bias
• promotes a systematic rather than ad hoc approach to the review process
• facilitates communication with others and promotes consistency between review team members 

*It is recommended that you register your systematic review protocol prior to conducting your review. This will improve transparency and reproducibility, and will also ensure that other research teams do not duplicate efforts. If you are working with the Cochrane or Campbell Collaborations, you will publish your protocol with those organizations.

Planning

Researchers want to develop a plan or protocol with their research team. Before diving further into the investigation, it is important to ensure someone has not previously conducted a systematic review on the same topic. There are are many databases to research published systematic reviews such as the Cochrane Library. 

According to the Methodological Expectations of Cochrane Intervention Reviews (MECIR) a protocol should identify:

• Background and Objectives
  • The context of the population or phenomenon. There is a pre-existing body of literature that should be used to examine why this review is important. 
    • The Objectives section should succinctly identify the research question. 
• Inclusion/exclusion criteria
  • This section identifies the study's scope including types of studies, participants' characteristics, and the pre-identified interventions being examined. Identify what will disqualify a study from being used in the review. 
• Search methods
  • What are the sources of information? This section will tentatively layout the intended search terms and databases or other information resources to be used. 
• Data Collection and Analysis
  • This is the information in studies used for analysis and the methods for obtaining the information. Criteria for bias assessment should be listed as well as technical information regarding statistical methods used for analysis and combining study results. 
• Other Information
  • This includes information such as declaration of interests, author acknowledgements and contributions, and support or funding resources. 

Preferred Reporting Items for Systematic Reviews and Meta-Analysis. The aim of the PRISMA Statement is to help authors improve the reporting of systematic reviews and meta-analyses. We have focused on randomized trials, but PRISMA can also be used as a basis for reporting systematic reviews of other types of research, particularly evaluations of interventions.