Meta-analysis is the statistical analysis of data from independent primary studies focused on the same subject. Key Points Meta-analytic approaches objectively appraise and synthesize outcomes across studies to determine statistical significance and relevance. Stage of meta-analysis: Formulate the research question. Identify or Understand relevant literature. Extract and consolidate study-level data. Locating primary studies Data appraisal and preparation. Synthesize study-level data into a summary measure. Exploratory analyses. Knowledge synthesis. ​Therefore, A, C, and D are the correct options. Additional Information It tries to give a quantitative assessment of the examined phenomenon, such as the effectiveness of an intervention. Narrative reviews are common in basic research, and attempts to examine past material in such a rigorous and quantitative manner are rare.