funnelplot: Funnel plot for publication bias

In rmeta: Meta-Analysis

Description

Plots the treatment difference for trials against the size of the trial (or other specified variable). Asymmetry in the plot often indicates publication bias. Generic, with methods for meta-analysis objects.

Usage

funnelplot(x,...)
## Default S3 method:
funnelplot(x, se, size=1/se, summ=NULL,
        xlab="Effect", ylab="Size", colors=meta.colors(),
        conf.level=0.95, plot.conf=FALSE,
        zero=NULL, mirror=FALSE, ...)

Arguments

x	Treatment difference
se	Standard error of x
size	Variable for the vertical axis
summ	summary treatment difference
xlab	x-axis label
ylab	y-axis label
colors	list of colors for components of the plot
conf.level	For confidence interval plotting
plot.conf	Plot confidence intervals instead of just points?
zero	location of a null hypothesis line
mirror	Add points reflected around summ?
...	further arguments to be passed from or to methods.

Details

With the default value of size the plot should appear as a upwards-pointing funnel shape. Publication bias often causes one side of the funnel to be trimmed near the base. The mirror plot creates a symmetric funnel by reflecting the plot around the summ value. In the presence of publication bias the added points will separate from the real studies.

Value

Used for its side-effect.

Author(s)

Thomas Lumley

See Also

meta.DSL, meta.MH, meta.summaries, metaplot

Examples

data(catheter)
a <- meta.MH(n.trt, n.ctrl, col.trt, col.ctrl, data=catheter,
             names=Name, subset=c(13,6,5,3,7,12,4,11,1,8,10,2))
funnelplot(a$logOR, a$selogOR)
funnelplot(a$logOR, a$selogOR,
           plot.conf=TRUE, summ=a$logMH, mirror=TRUE)
funnelplot(a, plot.conf=TRUE)

Example output

Loading required package: grid

rmeta documentation built on May 2, 2019, 1:10 p.m.