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ERIC Number: EJ747791
Record Type: Journal
Publication Date: 2006-Jun
Pages: 14
Abstractor: Author
Reference Count: 0
ISSN: ISSN-1082-989X
Assessing Heterogeneity in Meta-Analysis: Q Statistic or I[squared] Index?
Huedo-Medina, Tania B.; Sanchez-Meca, Julio; Marin-Martinez, Fulgencio; Botella, Juan
Psychological Methods, v11 n2 p193-206 Jun 2006
In meta-analysis, the usual way of assessing whether a set of single studies is homogeneous is by means of the Q test. However, the Q test only informs meta-analysts about the presence versus the absence of heterogeneity, but it does not report on the extent of such heterogeneity. Recently, the I[squared] index has been proposed to quantify the degree of heterogeneity in a meta-analysis. In this article, the performances of the Q test and the confidence interval around the I[squared] index are compared by means of a Monte Carlo simulation. The results show the utility of the I[squared] index as a complement to the Q test, although it has the same problems of power with a small number of studies.
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Publication Type: Journal Articles; Reports - Evaluative
Education Level: N/A
Audience: N/A
Language: English
Sponsor: N/A
Authoring Institution: N/A