Meta Analysis and Systematic Review
A systematic review provides a detailed analysis of the current state of knowledge available on a certain topic. The purpose is to comprehensively present and synthesize all the available evidence pertainign to a given treatment method or diagnostic technique. The strength of a systematic review is that is includes original studies according to predefined inclusion and exclusion criteria, thus limiting bias. By contrast, in an un-systematic (narrative) review, the author is free to include whatever data they choose, which can be biased based on the particular author's perspective.
If a sufficient number of Randomized controlled trials or observational studies exist reporting the same outcome, these results may be pooled or statistically combined in order to calculate a larger, combined effect. This is called a Meta Analysis, and is the most compelling level of scientific evidence, particularly if it is based on data from pooled RCTs.
- Systematic in the collection of data
- Effective at assessing the efficacy of a specific intervention
- Can only be conducted if there is a sufficient number of similar studies