Keywords
Meta-analysis
Research synthesis
Synthesis methods Revisión sistemática
Meta-análisis
Síntesis de la investigación
Métodos de síntesis
How to Cite
Abstract
Systematic reviews (SR) and meta-analyses (MA) are essential research methodologies for the rigorous accumulation of knowledge in any empirical science. While MA enable more robust conclusions regarding the question of interest, the necessary conditions for their implementation are not always met. In such cases, SR can be conducted as an alternative. This tutorial examines the key similarities and differences between SR and MA, with a focus on the methodological processes involved in conducting an SR without MA. The phases discussed include formulation of the research question, definition of inclusion and exclusion criteria, literature search, data extraction, risk of bias assessment, outcome measurement, synthesis methods, and report writing. Special attention is given to two core features that distinguish SR from MA: the measurement of study outcomes (e.g., effect sizes, probability levels, direction of effects) and quantitative synthesis methods alternative to those typically employed in MA. An example is used throughout to illustrate each phase of the SR process. Finally, the tutorial discusses on the strengths and limitations of SR in comparison to MA.
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