What is a meta -analysis?
meta -analysis is an analytical overview of several research studies on a common topic. Scientific research is based on statistical findings, but these studies are often limited by the sample size, because only a small sample of possible data can be obtained during the project. The aim of the meta -analysis is to overcome this difficulty by combining findings from several studies and create a more complex image of the research problem. Although this type of analysis has advantages, it also has disadvantages such as distortion of selection and possible distortion of statistics that can lead to false conclusions.
meta-analysis can be performed in any field of study where there is a set of statistical research literature. However, in order to be valid, the analysis must be done systematically, as a research study itself. After creating the problem, some studies are selected for the analysis based on specific criteria.
The nature of the criteria dependent meta -analysis. For example, a researcher performing a meta -analysis of treatment in patients sufferingHe played studies specifically about this topic. The researcher can further narrow the selection of literature by selecting only studies that have been performed with appropriate methodology. For example, a randomization requirement or a random selection of samples to prevent distortion can be a criterion for inclusion.
After the collection and review of studies, statistical methods are used to combine and filter data. Since the size of the sample in the meta -analysis is in a normal research study effectively much greater than the size of the sample, it may be possible for the analysis to reveal statistical patterns that a single study could not show. Small sample of one research study can also increase certain random effects from progortin. Meta -analysis can be used to solve the contradictions between studies resulting from such random fluctuations.
Perhaps the biggest disadvantage of the meta -analysis process is the problem of choice. Since the researcher siThey must choose which studies to be included in their analysis are unavoidable distortion in overall statistical conclusions. A researcher with a given agenda could distort the selection to prefer some conclusions to others. Although the theme of the analysis is sufficiently narrow that all available literature can be reviewed, unpublished studies will not be included. Critics of meta -analysis point to this as evidence that this process is not really objective or scientific.