Meta-analysis


Pyramid of Research Validity
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http://www.library.mq.edu.au/libguides/study_design_final_6.jpg

Strengthened Overall Research

Meta-analysis pools the important qualitative and quantitative results of a single study into a larger group. Doing so statistically increases the validity of the study altogether. Before the data can be collected, the analyst has to deem the trial combinable to the original study in hopes that the data can be re-analyzed. The use of meta-analysis uses an increased number of studies, more diverse population of studies, and previous statistically proven results to produce concrete numbers driven data.

Two-Step Process

The method of meta-analysis can be broken down in to a two-step process. The first involves extracting all the relevant data and calculating the results for that data, while the second part decides whether or not to create a pooled result. It is important to remember that meta-analysis should be used to help strengthen the results of the original study and should be treated as one big trial.

Highest Quality of Evidence

When it comes to the use of evidence based medicine in health care research, meta-analysis is at the highest spectrum for quality of evidence. Meta-analysis can be used to prove hypotheses and answer specific questions such as 'does this behavior affect this scenario?' Meta-analysis provides a singular organized overview of the data which helps examine specific questions.

Numerical Graph using Meta-analysis
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Benefits
  • Greater strength of data
  • Greater comparison of data
  • Greater ability to further project data
  • Considered based on evidence research

Drawbacks
  • Can be a very lengthy process and time consuming as well
  • Some studies could lack all of the data creating a skewed result
  • Advanced statistical analyse methods needed
  • Similarity of study is unaccounted for

Related Words:
Quantitative synthesis, pooling, systematic review

Systematic Review is used interchangeably with the term meta-analysis, and this is not entirely true. Systematic review is strictly the entire process of collecting, reviewing, and presenting the available research, while meta-analysis is solely the statistical method used to withdrawal and combine the data. Meta-analysis should be based upon systemic review, but that does not mean that systemic review will develop into a meta-analysis.

Resources:
http://www.cochrane-net.org/openlearning/html/mod12-2.htm
http://www.gwumc.edu/library/tutorials/studydesign101/metaanalyses.html
http://www.cochrane-net.org/openlearning/html/mod3-2.htm
http://www.slideshare.net/DineshSelvam1/meta-analysis-qualitative-research-design