[R-meta] Help with variance stabilizing transformation methods in Metafor
Thank you for the tip Wolfgang! Silly of me not to have thought of that... Then I guess you have helped me out with everything! Regards, Todor On 17 January 2018 at 22:28, Viechtbauer Wolfgang (SP) <
wolfgang.viechtbauer at maastrichtuniversity.nl> wrote:
Just divide the person times by 100 before the analysis. See: http://www.metafor-project.org/doku.php/analyses: stijnen2010#poisson-normal_model_for_the_meta-analysis_of_incidence_rates Then the forest plot will automatically show you rates per 100 pt yrs. Best, Wolfgang -----Original Message----- From: R-sig-meta-analysis [mailto:r-sig-meta-analysis- bounces at r-project.org] On Behalf Of Todor Krastev Sent: Wednesday, 17 January, 2018 21:34 To: Guido Schwarzer Cc: r-sig-meta-analysis at r-project.org Subject: Re: [R-meta] Help with variance stabilizing transformation methods in Metafor Dear Guido, Thank you for your prompt reply! It took me some time to fix it and react to your email, but I did manage in the end to fit the Poisson-normal model as described in Stijnen (2010), which led to much more logical effect estimates in my meta-analysis. I didnt quite succeed to work it out with the Meta package due to some errors in the GLMM function and changed the decimal places manually (x100) in Metafor to obtain the numbers as %. As you can see in the attachment, I also obtained the 0.73 value with Poisson (see attachment). Also, maybe Wolfgang knows an simpler way to transform Forest plot values in Metafor also to achieve numbers per 100 pt yrs? I also checked out the Meta package and does look super neat in the way it presents the individual study estimates in grey colour (makes the 95%CI visible in large studies) and also automatically gives you the weighing of studies and the measure of heterogeneity (all these I had to add manually). It definitely got my attention and I shall try it out for my next project. Thank you once again for your great help! Regards, Todor