What is a systematic review?

A systematic review is rigorous process of reviewing all relevant literature on a given topic for the purpose of answering a well defined question or set of questions.

Systematic reviews are used in the creation of medical practice guidelines, they are used to inform social and health related policy decisions and they are used to assess the current state of knowledge in specific areas. Of course, there are many other uses for the systematic review process, but these areas are where the majority of work is being done today.

Why conduct a systematic review?

There are many reasons why systematic reviews are considered to be a powerful research tool:

  1. Because they look at the total body of work on a given topic, they provide statistically more powerful results than single studies
  2. Reviews are typically much less expensive and time consuming than primary research
  3. Unlike primary medical research, there is no significant regulatory overhead associated with conducting a review
  4. If done before a primary study, their results can be used to “tune” the primary study to address only the missing questions or, in the case of a medical therapeutic study, to make the study safer with fewer patient interventions