Systematic Reviews
Learn more about the WHSC Library Systematic Review Service, access the Systematic Review Request Form, and read about guidance on conducting these types of reviews on our Systematic Reviews Guide.
Defining Evidence Synthesis
Evidence synthesis is “a way of combining information from multiple studies that have investigated the same thing, to come to an overall understanding of what they found” (Cochrane). Systematic reviews and scoping reviews are types of evidence synthesis in which a research team seeks to find and synthesize all scholarly research on a given topic. Evidence synthesis projects are conducted with strict methodologies to ensure that the reviews are reproducible, transparent, and unbiased.
The Review Process
Conducting this type of research is a time-intensive process that can take several months to a year to complete and requires a team of independent reviewers. Systematic and scoping reviews involve strict methodologies and reporting guidelines which must be followed. A typical process looks something like this:
- An a priori protocol is completed and registered in a registry such as PROSPERO
- An extensive literature search is conducted across multiple databases
- The results are screened by independent researchers blinded to each other’s decisions in a tool such as Covidence
- The full texts of the included reports are reviewed
- The results from these included reports are synthesized narratively and/or statistically through meta-analysis
- The manuscript is written according to PRISMA Reporting Guidelines.
The WHSC Library Systematic Review Team
Informationists from the WHSC Library can support research teams wanting to conduct a systematic or scoping review. Learn more about the Tier 1 and Tier 2 services we offer, as well as guidance on different types of reviews, conducting evidence synthesis projects, and tools to assist with these types of reviews at our Systematic Reviews Guide.
Systematic versus Scoping Reviews
Systematic reviews typically address a specific, answerable question which often in the form of a PICO question. Some examples of specific, answerable PICO questions include the following:
- How do the outcomes of dorsal bridge plating compare to volar locking plate fixation in the treatment of isolated distal radius fractures in patients aged 60 years and older?
- Is gabapentin compared to placebo effective in decreasing pain symptoms in middle-aged male amputees suffering from phantom limb pain?
Scoping reviews typically address a broader question with the intent to evaluate the scope of the existing literature and where further research is needed. These questions can be in the form of the PICO framework or other research question frameworks. Some examples of scoping review questions include:
- How are isolated distal radius fractures treated in low to middle-income countries in patients aged 60 years and older?
- What are the experiences of women undergoing IVF treatment as assessed by a particular tool?
Systematic Review Service
The WHSC Library offers systematic review support services. Click here to find out more or submit a support request.
