What do you study in a systematic review?

Systematic reviewsrequire more time and manpower than traditional literature reviews. Before beginning a systematic review, researchers should address these questions:

Is there is enough literature published on the topic to warrant a review?

Systematic reviews are designed to distill the evidence from many studies into actionable insights. Is there a body of evidence available to analyze, or does more primary research need to be done?

Can your research question be answered by a systematic review?

Systematic review questions should be specific and clearly defined. Questions that fit the PICO (problem/patient, intervention, comparison, outcome)formatare usually well-suited for the systematic review methodology. The research question determines the search strategy, inclusion criteria, anddata that you extract from the selected studies, so it should be clearly defined at the start of the review process.

Do you have a protocol outlining the review plan?

The protocol is the roadmap for the review project. A good protocol outlinesstudy methodology,includes the rationale for the systematic review, and describes thekey questionbroken into PICO components. It is also a good place to plan outinclusion/exclusion criteria, databases that will be searched, data abstraction andmanagement methods, and how the studies will be assessed for methodological quality.

Do you have a team of experts?

A systematic review is team effort. Having multiple reviewers minimizes bias and strengthens analysis. Teams or often composed ofsubject experts, two or more literature screeners,a librarian to conduct the search, and a statistician to analyze the data.

Do you have the time that it takes to properly conduct a systematic review?

Systematic reviews typically take 12-18months.

Do you have a method for discerning bias?

There are many types of bias, including selection, performance, & reporting bias, and assessing the risk of bias of individual studies is an important part of your study design.

Can you afford to have articles in languages other than English translated?

You should include all relevant studies in your systematic review, regardless of the language they were published in, so as to avoid language bias.