[R-meta] Mismatch between output from sub-group analysis and forest plot

[Joao Afonso]

Dear all,

I am conducting a meta-analysis on prevalence and incidence data. As there
is plenty of heterogeneity I am doing a sub-group analysis. However I am
finding the output of the same and forest plots produced to have different
values for the pooled estimates. I am using the double arcsine
transformation and then have the data back-transformed to produce the
estimates. The model is the following:




















*iies.da.lcmbi<-ies.da %>%  filter(is.na
<http://is.na>(lcmbi)==FALSE)subganal.lcmbi=rma(yi, vi, data=ies.da.lcmbi,
mods=~lcmbi, method="DL")pes.da.lcm=rma(yi, vi, data=ies.da.lcmbi,
mods=~lcmbi=="Records", method="DL")pes.da.records=rma(yi, vi,
data=ies.da.lcmbi, mods=~lcmbi=="Locomotion Scoring Method",
method="DL")pes.subg.lcmbi=predict(subganal.lcmbi,transf=transf.ipft.hm
<http://transf.ipft.hm>,targ=list(ni=prevalence_2020_cow_nomv$ssizeanimal))dat.samevar=data.frame(estimate=c((pes.da.lcm$b)[1],
(pes.da.records$b)[1]),stderror=c((pes.da.lcm$se)[1],
(pes.da.records$se)[1]),tau2=subganal.lcmbi$tau2)pes.da.lcmbi=rma(estimate,
sei=stderror,method="DL",data=dat.samevar)pes.lcmbi=predict(pes.da.lcmbi,
transf=transf.ipft.hm <http://transf.ipft.hm>,
targ=list(ni=prevalence_2020_cow_nomv$ssizeanimal))print(pes.da.lcm,
digits=3) print(pes.da.records, digits=3) print(subganal.lcmbi,
digits=3)print(pes.lcmbi, digits=3) *


And to produce the forest plot I use the following code:

*subganal.lcmbi=rma(yi, vi, data=ies.da.lcmbi, mods=~lcmbi, method="DL")*
*pes.summary=metaprop(*nlameanimal*, *ssizeanimal*, author,
data=ies.da.lcmbi,*
*                     sm="PFT",*
*                     method.tau="DL",*
*                     method.ci <http://method.ci>="NAsm",*
*                     byvar=lcmbi,*
*                     tau.common=TRUE,*
*                     tau.preset=sqrt(subganal.lcmbi$tau2))*
*precision=sqrt(ies.da.lcmbi$vi)*
*jpeg(file="forest_cow_cow_lcmbi.jpeg", width=11, height=12, units="in",
res=300)*
*forest(pes.summary,*
*       xlim=c(0,1),*
*       pscale=1,*
*       rightcols=FALSE,*
*       leftcols=c("studlab", "effect", "ci"),*
*       leftlabs=c("Study", "Prevalence", "95% C.I."),*
*       text.random="Prevalence of Lameness in British Dairy Cattle",*
*       bylab = "Lameness Data Source",*
*       print.byvar = TRUE,*
*       xlab="Prevalence of Lameness", smlab="",*
*       weight.study="random", squaresize=0.5, col.square="navy",*
*       col.diamond="maroon", col.diamond.lines="maroon",*
*       pooled.totals=FALSE,*
*       comb.fixed=FALSE,*
*       fs.hetstat=10,*
*       print.tau2=TRUE,*
*       print.Q=TRUE,*
*       print.pval.Q=TRUE,*
*       print.I2=TRUE,*
*       digits=2,*
*       sortvar = precision)*
*dev.off()*

What could I be doing wrong? I will be extremely grateful for any help or
guidance.

Wishing all a great afternoon,

Joao
-- 
João Afonso
DVM, MSc Veterinary Epidemiology
PhD Student
Department of Infection and Global Health
University of Liverpool
+351914812305

	[[alternative HTML version deleted]]