How important should the significance level be in the decision process to include single results in a Meta-Analysis?
In a Meta-Analysis of different studies some of the included studies describe their results as insignificant. The outcomes of the single studies are reported for control and intervention groups separately and should be included in the Meta-Analysis.
- Does the principle of a meta-analysis permit the inclusion of single insignificant results?
- Has the insignificance of single studies to be accounted for in the calculation of the overall effect of the meta-analysis?