help doiplot (See also: https://www.epigear.com/index_files/metaxl.html)

Title

doiplot -- A postestimation program after metan for the visualization of asymmetry and heterogeneity in meta-analysis

Syntax

doiplot varlist [if] [in] [, options]

varlist should contain the two variables created by a prior run of metan as part of the result set in the form of:

_ES _seES (effect size and standard error) Ratio-based or proportion effect estimates will automatically be appropriately transformed by metan.

Description

doiplot generates the Doi plot and its variants (combinations with the funnel and Galbraith plots).
The plots also include the LFK index and Egger's test P-value as a note.
The Doi plot replaces the conventional scatter (funnel) plot of precision versus effect with a folded normal quantile (Z-score) versus effect plot.
Combined with the Galbraith plot, the Doi-Galbraith plot delivers a combined graphical overview of both study symmetry and heterogeneity at a glance.

Options

dg (the default) plots an overlay of the Doi plot and Galbraith plot with a note reporting the LFK index.

df plots an overlay of the Doi plot and the funnel plot with a note reporting the LFK index and Egger’s P-value.

dp plots only the Doi plot with the LFK index as a note.

fp plots the conventional funnel plot with a note reporting Egger’s P-value.

gp plots the Galbraith plot.

Examples

The data for the example is taken from Ross Harris (2006), originally prepared for metan9.

. use http://fmwww.bc.edu/repec/bocode/m/metan_example_data, clear

Generating _ES _seES with metan.

. quietly metan tdeath tnodeath cdeath cnodeath, or ivhet nograph

The Doi-Galbraith plot.

. doiplot _ES _seES

The Doi-Funnel plot.

. doiplot _ES _seES, df

Authors

Chang Xu, Department of Population Medicine, College of Medicine, Qatar University, Qatar

xuchang2016@runbox.com

Luis Furuya-Kanamori, UQ Centre for Clinical Research, The University of Queensland, Australia

Suhail A.R. Doi, Department of Population Medicine, College of Medicine, Qatar University, Qatar

sardoi@gmx.net

References

Egger M, Davey Smith G, Schneider M, Minder C. Bias in meta-analysis detected by a simple, graphical test. BMJ. 1997;315(7109):629-634.

Furuya-Kanamori L, Barendregt JJ, Doi SAR. 2018. A new improved graphical and quantitative method for detecting bias in meta-analysis. Int J Evid Based Healthc 16: 195-203.

Furuya-Kanamori L, Xu C, Lin L, Doan T, Chu H, Thalib L, Doi SAR. P value-driven methods were underpowered to detect publication bias: analysis of Cochrane review meta-analyses. J Clin Epidemiol. 2020;118:86-92.

Galbraith R. Graphical display of estimates having differing standard errors. Technometrics, 1988; 30(3): 271–281

Funding

This work was supported by Program Grant #NPRP10-0129-170274 from the Qatar National Research Fund (a member of Qatar Foundation). The findings herein reflect the work and are solely the responsibility of the authors.

LFK was supported by an Australian National Health and Medical Research Council Fellowship (APP1158469).