Which research method combines data from multiple studies to provide the highest level of evidence?

A meta-analysis is a statistical technique that combines quantitative results from multiple independent studies addressing the same research question, producing a single pooled estimate with greater statistical power and precision than any individual study. Meta-analyses are typically conducted as part of a systematic review and sit at the top of the evidence hierarchy (level 1 evidence). In dentistry, Cochrane meta-analyses guide clinical guidelines on topics such as antibiotic prophylaxis, fluoride use, and surgical techniques.