Table 1.
Feature | Narrative review | Systematic review |
---|---|---|
Research question | Often unclear or broad | Specified and specific |
Literature sources and search | Not usually specified | Comprehensive sources (more than one database) and explicit search strategy |
Study selection | Not usually specified | Explicit selection criteria and selection by two independent reviewers |
Quality assessment included studies | Not usually present or only implicit | Critical appraisal on the basis of explicit quality criteria |
Synthesis | Often a qualitative summary | Often also a quantitative summary (meta-analysis) |