Study Design | Level of Evidence |
---|---|
Meta-analyses (MAs) | |
Systematic reviews (SRs) | |
Randomized controlled clinical trials (RCTs) | |
Non-randomized controlled clinical trials (Non-RCTs) | |
Cohort studies | |
Case-control studies | |
Crossover studies | |
Cross-sectional studies | |
Case studies | |
Consensus opinion of experts | |
Anecdotal reports or testimonies |