Heterogeneity measures
heterogi #Q #df [, level(#) format(%fmt) ncchi2 ]
where
#Q is the Cochran's Chi-Square or Q-test #df is the degrees of freedom
Description
heterogi provides the statistics H and I^2 to quantify heterogeneity in a meta-analysis.
Remark
It is an immediate command, see help immed. The Q-test can be obtained by metan or meta command. Options
level(#) specifies the width of the confidence interval; see help level.
format(%fmt) specifies the display format for presenting numbers in the table's cells.
ncchi2 specifies the use of the noncentral chi-squared distribution to calculate confidence intervals. The default is the test-based confidence interval (Higgins and Thompson, 2002).
Examples
. heterogi 14.4 24 . heterogi 14.4 24, level(99) . heterogi 14.1 11, nc . heterogi 81.5 19, nc f(%3.2f) . heterogi 41.5 7 . heterogi 130.3 3
Authors
Nicola Orsini, Division of Nutritional Epidemiology, IMM, Karolinska Institutet, Sweden Julian P.T. Higgins, MRC Biostatistics Unit, Cambridge, UK Matteo Bottai, Arnold School of Public Health, University of South Carolina, USA Iain Buchan, Northwest Institute for Bio-Health Informatics, University of Manchester, UK
Reference
Higgins J.P.T. and Thompson S.G., Quantifying heterogeneity in a meta-analysis, Statistics in Medicine, 2002, 21: 1539-1558
Support
http://nicolaorsini.altervista.org nicola.orsini@ki.se
Also see
On-line: help for metan, meta (if installed)