- Meta-analysis I
- Systematic reviews of RCTs
- Current practice guidelines
II
- Randomized controlled trials
- Controlled trials without III
randomization (quasi-experimental) - Cohort studies (epidemiologic) IV
- Case-controlled studies
(epidemiologic)
V
- Systematic review of descriptive
studies - Systematic review of qualitative
studies (meta-synthesis) - Correlational studies
VI
- Single descriptive study
- Single qualitative study
- Case series studies (epidemiologic)
- Case reports
- Concept analysis
- Opinion of authorities• Reports of expert committees VII
- Manufacturer's recommendations
- Tr aditional literature reviews
HIGHEST
LOWEST
FIGURE 1-1 Evidence Hierarchy
8 CHAPTER 1 What Is Evidence-Based Practice?