Before embarking on your systematic search, you'll want to define your research topic in an easily searchable way. This involves separating out the key concepts of your research question. There are various tools to help you do this. One of the most commonly used is PICO (pictured below). These worksheets can help you formulate a searchable question.
The PICO model is used for quantitative research and can also be utilized for qualitative research.
You can also use alternate models such as ECLIPSE or SPICE to construct your question.
Van de Voorde, C. & Léonard, C. (2007). Search for Evidence and Critical Appraisal: Health Services Research (HSR). Belgian Health Care Knowledge Centre http://www.kce.fgov.be/index_en.aspx?SGREF=5211ECLIPSE
Setting (What is the context of the question?)
Van de Voorde, C. & Léonard, C. (2007). Search for Evidence and Critical Appraisal: Health Services Research (HSR). Belgian Health Care Knowledge Centre http://www.kce.fgov.be/index_en.aspx?SGREF=5211
Image credit: Adapted by Charlotte Beck and Suzan Zagar, UBC Library from the EBM Generator. 2012. Levels of Evidence Pyramid.
The Levels of Evidence can be visualized in a pyramid structure. This pyramid is organized into information that is searchable through individual databases, which is broken down into filtered information and unfiltered information, and information that is not searchable via individual databases. The pyramid can be broken down as follows, beginning at the top of the pyramid going down:
Searchable via Individual Databases:
Not searchable through individual databases: Background information / Expert Opinion
When considering what type of studies to include in your systematic review, think about the evidence pyramid above. Higher quality studies near the top of the pyramid are considered the best source of evidence.