Systematic review is broadly defined as the rigorous evaluation and synthesis of a class of research by a specialized evaluation team, with a primary focus on identifying and retrieving international evidence related to one or more specific issues, evaluating and synthesizing research findings, providing guidance for practice, policy and in some cases further in-depth research. Systematic reviews are mainly used to reveal international evidence, identify areas that require further research, and identify conflicting research findings. According to the Cochrane Handbook, a systematic review is "the use of a clear, systematic approach designed to minimize bias, provide more reliable evidence, and from which to draw conclusions, make decisions". Systematic reviews follow structured steps and processes that adopt rigorous methodologies to guarantee the reliability and validity of research results. Therefore, systematic reviews can not only identify current evidence gaps, deficiencies, and trends, but can also be used to guide clinical decision-making, policy-making, and other important contents.
