[R-meta] Categorical mixed effect models and interpretation of results

[Alexander Sullivan (BIO - Student)]

Dear all,


In my meta-analysis I have [say] 100 experiments, from 30 studies, across 12 species. These experiments can be equally divided into two treatment levels [low and high]. If I want to determine if there is a significant difference in effect sizes between these two treatment levels would this be the right code:

res <- rma.mv(yi, vi, method = "REML", data = mydata, mods = ~factor(Treatment), random = ~1|Study_id)

... and then from the output of this model if the Qm statistic is significant I could say there is a significant difference in effect sizes between the two treatments?

Thank you for your time,


Alex


MSc Ecology and Conservation student
University of East Anglia, UK

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