[R-meta] Funnel Plots for Multilevel Meta

Dear Valeria,

You find discussion of these issues in the literature, for example:

https://www.bmj.com/content/343/bmj.d4002 (Sterne et al. 2011,
Recommendations for examining and interpreting funnel plot asymmetry in
meta-analyses) - One rule of thumb is that looking at a funnel plot
doesn't make much sense with less than 10 effects.

https://onlinelibrary.wiley.com/doi/full/10.1002/jrsm.1452 (Marks-Anglin
& Chen 2020, A historical review of publication bias)

https://onlinelibrary.wiley.com/doi/10.1002/jrsm.1468 (Page et al. 2020,
Investigating and dealing with publication bias and other reporting
biases in meta?analyses of health research: A review)

Best,

Gerta

Am 12.12.2020 um 14:43 schrieb Valeria Ivaniushina:

Dear Michael and Wolfgang.

at the end of Egger's regression / funnel plot thread, Wolfgang said: "To
what extent such a plot is indicative of publication bias / small study
effects is a different issue"

Could you please say more on this topic?
Particularly I am interested in this: is a plot with 8 effects

informative?

Or a plot with less than 20 effects?

Best,
Valeria

On Fri, Dec 11, 2020 at 11:28 PM Viechtbauer, Wolfgang (SP) <
wolfgang.viechtbauer at maastrichtuniversity.nl> wrote:

A funnel plot is simply a plot of the estimates against their standard
errors (or some other measure of precision). So one can draw such a plot
whether there are multiple estimates from the same study or not. Hence,
funnel() in metafor will happily do so:

library(metafor)

dat <- dat.konstantopoulos2011
res <- rma.mv(yi, vi, random = ~ 1 | district/school, data=dat)
res
funnel(res)

One could indicate (with different colors or plotting symbols) which
estimates belong to the same study.

cols <- palette.colors(length(unique(dat$district)), palette="Alphabet")
cols <- cols[as.numeric(factor(dat$district))]
funnel(res, col=cols)

Then one can see how points from the same study (or in this case,
'district') cluster together.

To what extent such a plot is indicative of publication bias / small

study

effects is a different issue (but the same applies even to simpler
meta-analyses with a single estimate per study).

Best,
Wolfgang

-----Original Message-----
From: R-sig-meta-analysis [mailto:

r-sig-meta-analysis-bounces at r-project.org]

On Behalf Of Dylan Johnson
Sent: Friday, 11 December, 2020 20:03
To: Michael Dewey; r-sig-meta-analysis at r-project.org
Subject: Re: [R-meta] Funnel Plots for Multilevel Meta

Hi Michael,

Would it not be nonsensical to have multiple effects from the same

article

in the funnel plot though?

With the Egger's regression I was able to accommodate the fact that

their

is

nonindependence of the effects, but am unsure how to proceed with a

funnel

plot.

Dylan

Dylan Johnson, MSc

MA Student, School and Clinical Child Psychology
Department of Applied Psychology and Human Development

University of Toronto
252 Bloor Street West

Toronto, ON M5S 1V6

From: Michael Dewey<mailto:lists at dewey.myzen.co.uk>
Sent: December 11, 2020 6:12 AM
To: Dylan Johnson<mailto:dylanr.johnson at mail.utoronto.ca>; r-sig-meta-
analysis at r-project.org<mailto:r-sig-meta-analysis at r-project.org>
Subject: Re: [R-meta] Funnel Plots for Multilevel Meta

Dear Dylan

Perhaps I misunderstand you but if you have the data for a regression
type test like Egger's do you not just plot that? The funnel() function
in metafor does that and I am sure equivalent solutions can be found in
meta and many other packages.

Michael

On 11/12/2020 01:14, Dylan Johnson wrote:

Hello,

Thanks everyone for helping me sort out the Egger's test with

multi-level

meta modelling!

Is there any option in R for producing Funnel plots that are

appropriate

for the nonindependence? I imagine that the standard funnel plot would

be

deceiving if it came from a multi-level design.

Many thanks!

Best,
Dylan

Dylan Johnson, MSc

MA Student, School and Clinical Child Psychology
Department of Applied Psychology and Human Development

University of Toronto
252 Bloor Street West

Toronto, ON M5S 1V6

      [[alternative HTML version deleted]]