[R-meta] Dear Wolfgang

[Ju Lee]

Dear Wolfgang,

I hope you are doing well.

My research group is currently working on a project where they are trying to compare effect sizes generated from their current mixed-effect meta-analysis with effect sizes (based on similar response variables) calculated in other meta-analysis publications.

We are currently using log response ratio and are trying to make some statement or analysis to compare our grand mean effect sizes with other studies. In more details, we are examining how herbivorous animal control plant growth in degraded environment. Now, there is already a meta-analysis out there that has examined this (in comparable manner) in natural environment as opposed to our study.

My colleagues want to know if there is a way to make some type of comparison (ex. whether responses are stronger in degraded vs. natural environemnts) between two effect sizes from these different studies using statistical approaches.
So far what they have from other meta-analysis publication is grand mean hedges'd and var which they transformed to lnRR and var in hopes to compare with our lnRR effect sizes.

My view is that this is not possible unless we can have their actual raw dataset and run a whole new model combining with our original raw dataset. But I wanted to reach out to you and the community  if there is an alternative approaches to compare mean effect sizes among different meta-analysis which are assumed to have used similar approaches in study selection and models (another issue being different random effect structures used in different meta-analysis which may not be very apparent from method description).

Thank you for reading and I hope to hear from you!
Best,
JU

	[[alternative HTML version deleted]]