is a research technique for combining the results of all the published and even unpublished results on one question and drawing a conclusion based on the entire set of studies on the topic.

The research technique you're referring to is called a Meta-Analysis. Here are the steps involved in conducting a Meta-Analysis:

1. Formulate the Problem: Clearly define the research question you want to answer. This includes specifying the population, the interventions or exposures, the comparators, and the outcomes.

2. Search for Relevant Studies: Conduct a comprehensive search of published and unpublished studies that address your research question. This often involves searching multiple databases and other sources.

3. Select Studies: Apply pre-determined inclusion and exclusion criteria to select the studies that are relevant to your research question.

4. Extract Data: Extract relevant data from the selected studies. This often includes information about the study design, the population, the interventions or exposures, the outcomes, and the results.

5. Assess Study Quality: Assess the quality of the selected studies. This often involves evaluating the risk of bias in the studies.

6. Analyze Data: Use statistical methods to combine the results of the selected studies. This often involves calculating a pooled effect estimate.

7. Interpret Results: Interpret the results of the meta-analysis in the context of the overall evidence. This includes considering the quality of the studies, the consistency of the results, and the relevance of the results to your research question.

8. Report Results: