




Sterne, Jonathan A.C.; Harbord, Roger M.. 
Funnel plots are a visual tool for investigating publication and other bias in metaanalysis. They are simple scatterplots of the treatment effects estimated from individual studies (horizontal axis) against a measure of study size (vertical axis). The name “funnel plot” is based on the precision in the estimation of the underlying treatment effect increasing as the sample size of component studies increases. Therefore, in the absence of bias, results from small studies will scatter widely at the bottom of the graph, with the spread narrowing among larger studies. Publication bias (the association of publication probability with the statistical significance of study results) may lead to asymmetrical funnel plots. It is, however, important to realize that... 
Tipo: Journal Article 
Palavraschave: Metafunnel; Funnel plots; Metaanalysis; Publication bias; Smallstudy effects; Research Methods/ Statistical Methods. 
Ano: 2004 
URL: http://purl.umn.edu/116233 
 


Harris, Ross J.; Bradburn, Michael J.; Deeks, Jonathan J.; Harbord, Roger M.; Altman, Douglas G.; Sterne, Jonathan A.C.. 
This article describes updates of the metaanalysis command metan and options that have been added since the command’s original publication (Bradburn, Deeks, and Altman, metan — an alternative metaanalysis command, Stata Technical Bulletin Reprints, vol. 8, pp. 86–100). These include version 9 graphics with flexible display options, the ability to metaanalyze precalculated effect estimates, and the ability to analyze subgroups by using the by() option. Changes to the output, saved variables, and saved results are also described. 
Tipo: Article 
Palavraschave: Metan; Metaanalysis; Forest plot; Research Methods/ Statistical Methods. 
Ano: 2008 
URL: http://purl.umn.edu/120926 
 


