Evidence Hierarchies

Evidence hierarchies are systems that rank different types of information based on their reliability and strength in supporting conclusions or decisions. At the top are systematic reviews and meta-analyses, which summarize and analyze multiple studies. Below them are randomized controlled trials, followed by cohort and case-control studies. Observational studies and expert opinions come next, being less robust due to potential biases. This hierarchy helps people assess which evidence carries more weight, ensuring informed decisions in fields like medicine, policy, and research. Essentially, it guides us in discerning credible sources from less trustworthy ones.