[R-meta] Fwd:

[Im]

Dear All!
Thanks a lot everyone for helping me to conduct the meta analyses and
making me reach to results stage of the manuscript.

However, I still have some crucial questions regarding interpretation of
meta-analysis with HR values, alongwith meta-analysis of their respective
P-values.


*Data Collection:*

Mainly, I have gathered *2-4 P values each of Hazard Ratios (HR values
given with CIs) from studies on* *specific* *prognostic markers
reporting* *DFS,
OS and DSS*.


*R Studio Codes for meta-analysis of HR values:*

*library(meta)*


*settings.meta(digits = 2, layout = "RevMan5") *

*HR <- c(1.34,1.95)
                             ** (Hypothetical values)*

*  lower.HR <- c(1.10,0.75)        *

*upper.HR <- c(2.34,2.25)       *

*     study<- c("ABC et al. 2018","EFG et al. 2020")*

*m2<-metagen(log(HR),lower=log(lower.HR),upper=log(upper.HR),studlab=study,sm="HR")*

*m2*

*forest(m2)*


*  grid::grid.text("Meta-analysis of Prognostic marker for Multivariate
DFS",                 0.5, 0.94, gp = grid::gpar(cex = 1.5)) *


*R Studio Codes for meta-analysis of P values:*

*install.packages("BiocManager")*



*BiocManager::install("multtest")*



*install.packages("metap")*



*library(metap)*



*pvals <- c(0.08,0.3)            **(Hypothetical values)*



*result <- sumlog(pvals)*



*result*


*Results of Meta-analysis with P values:*

1. chisq =  16.66974  with df =  4  p =  0.002240369


2. chisq =  35.80921  with df =  8  p =  1.902998e-05   (Do we report this
result as 0.000019 in the manuscript ?)



*Questions:*


1.Please view attached first image of forest plot which I have got from
"Meta" Package in RStudio. The P value in this forest plot is for
heterogeneity, but the P value for overall effect size is not there as
presented in the second attached image as: *(Test or overall effect z=0.35,
p=0.7)*. Should I, and if "yes" then how to report this P value in my
forest plot ?

And is this P value similar to the P value which I am getting from
meta-analysis of P values with "metap" package ? which P value to be
reported ideally and usually ?


2. Regarding *"metap*" package my cumulative P values are too low, so how
to interpret these results. Is there no image OR forest plot for them to
report ? Does the significance level (0.005) changes for cumulative P
values ?


3. Can I report these cumulative P value meta-analysis results along
with regular meta-analysis of cumulative HR values (forest plots) ?


I will be much grateful for your much valuable expert advice to finalize my
results.
best regards,
Imran

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