Click each tab to learn more about the advantages and disadvantages of SLRs.
If done properly, all relevant research (all sources, types, and languages) is identified and appraised .
People who need to know the overall answer to a question from all currently available studies can get a quick answer.
Their conclusions come from a combination of multiple studies that have been assessed for relevance and quality.
Systematic reviews tend to be widely cited by other researchers.
The best available information can be applied in daily professional life.
It can take time to thoroughly conduct an SLR and formally publish it.
A systematic review needs to be regularly updated to include all new published primary research that has accumulated since starting.
For example, there may only be one randomized controlled trial, or only best practice guidelines or consensus statements from scholarly or professional associations.
This is known as “garbage in, garbage out” (or “GIGO”).
Unfortunately, some research studies are of poor quality or poorly performed. Others are incompletely reported or partially duplicate data.
Systematic reviewers should include comments appraising the evidence sources, warnings on how trustworthy the overall conclusions are, and recommendations on future primary studies needed.
Some studies are biased or simply never published (called “publication bias”), because researchers and journals tend to prefer to publish only “positive” results.