META-ANALYSIS: DEFINITION, APPLICATIONS AND SYNERGY WITH SPATIAL DATA

Abstract

The concept of meta-analysis is defined and considerations about the origin and meaning of the term are given . A historical approach shows that the underlying idea have been applied in several research areas. Applications in medicine, agriculture and ecology are presented. Meta-analysis is described as a synthesis of the past research on a stated topic which presents emphasis in generation of quantitative conclusions. It is not a data analysis specific technique, but rather a paradigm from which the researcher has a new approach to joint another's results and conclusions. Some sources of data on which meta-analysis may be practiced are presented. These data are often from published papers, but may be from customary records of several institutions, or be a mix of these two types with new data, collected by the proper meta-analysis executing researcher. The potential synergy between meta-analysis and spatial data analysis in agricultural research is highlighted. Care in application are recommended in relation to data bias and its adequacy to proposed objectives. The conclusion is that, as any tool, the meta-analysis is not a panacea, but in some cases it presents obvious advantages, such as, costs/benefit relation. It is a challenge to know it well so as to use it.