A scoping study can be defined as:"..a form of knowledge synthesis that addresses an exploratory research question aimed at mapping key concepts, types of evidence, and gaps in research related to a defined area or field by systematically searching, selecting and synthesizing existing knowledge." (from: Colquhoun, H. L., Levac, D., O'Brien, K. K., Straus, S., Tricco, A. C., Perrier, L., . . . Moher, D. (2014). Scoping reviews: Time for clarity in definition, methods, and reporting. Journal of Clinical Epidemiology,(12), 1291-1294. ).
Common reasons for conducting a scoping study:
Scoping studies typically involve six steps:
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)
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 |