Meta-analysis.

Meta-analysis is a research method that systematically combines information from a number of research studies to draw one or more conclusions from the body of available evidence. Meta-analysis is most useful in addressing questions for which a substantial body of high-quality research already exists, because the quality of the conclusions drawn by a meta-analysis depends in large part on the quality of the studies included. Meta-analysis can be particularly useful when studies have produced inconsistent or conflicting results. As the number of published research studies on a particular topic increases, meta-analysis is an important tool to help make sense of the available evidence.