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Gerstein Science Information Centre

Systematic & Scoping Reviews : Methodology Behind the Search Strategies

This guide is primarily for students and other researchers conducting systematic reviews and scoping reviews for coursework, thesis/dissertation requirements, or for other research purposes.

Differences between systematic and scoping reviews

Scoping studies differ from systematic reviews in several ways:

  Scoping review Systematic review
Research question Broadly defined Highly focused
Inclusion/Exclusion criteria Developed post hoc at study selection stage Developed at protocol stage
Study selection All study types Defined study types
Data extraction “Charts”  data according to key issues, themes, etc. Synthesizes & aggregates findings

HOWEVER both systematic reviews and scoping reviews require comprehensive and structured searches of the literature to maximize recall and decrease bias.


Additional information:

Guide to Knowledge Synthesis from Canadian Institutes of Health Research (CIHR)

Arksey, H., & O'Malley, L. (2005). Scoping studies: Towards a methodological framework.  International Journal of Social Research Methodology: Theory and Practice, 8 (1), 19-32. doi:10.1080/1364557032000119616


Difference between narrative reviews and evidence syntheses

Evidence syntheses differ from traditional narrative or literature reviews in several ways:

Narrative review Evidence Synthesis
Search methods not systematic, nor validated, nor peer reviewed systematic, highly structured to minimize bias ; conducted much like other scientific studies
Inclusion/Exclusion criteria Not explicitly stated Included in protocol or developed post hoc
Bias potential for authors to selectively include or exclude studies to support a position attempts to minimize bias based on protocol, non-selective reporting of outcomes and transparent and reproducible search strategies
Replication & updating Difficult since search methodology not reported in detail in methods section nor included in full in the appendices Designed to be reproducible and facilitate updating