Dear all,
Sorry for the double posting and previous "messy" message. 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(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,
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,
targ=list(ni=prevalence_2020_cow_nomv$ssizeanimal))
print(pes.da.lcm, digits=3)
print(pes.da.records, digits=3)
print(subganal.lcmbi, digits=3)
print(pes.lcmbi, digits=3)
And to produce the forest plot I use the following code:
subganal.lcmbi=rma(yi, vi, data=ies.da.lcmbi, mods=~lcmbi, method="DL")
pes.summary=metaprop(nlameanimal, ssizeanimal, author, data=ies.da.lcmbi,
sm="PFT",
method.tau="DL",
method.ci="NAsm",
byvar=lcmbi,
tau.common=TRUE,
tau.preset=sqrt(subganal.lcmbi$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