Duplicating meta-regression results from PROC MIXED with lmer
Rolf, I actually don't believe that this is a SAS vs R issue since I have 3 sources that report the same results. I know that STATA, SAS and the mima function from R can all be used to give the correct results. The question is related more to how I can get similar results with lmer. Currently, the code I provided generates VERY different results, especially related to between study variance estimation (tau) and regression coefficient standard errors. Basically, I think I got it all wrong in my coding of the models with covariates (f3 and f4), but I can't understand why. Brant
On May 5, 2009, at 11:43 PM, Rolf Turner wrote:
On 6/05/2009, at 3:00 PM, Brant Inman wrote:
R-experts: In 2002, Hans Van Houwelingen et al. published a tutorial on how to do meta-regression in Statistics in Medicine. They used the classic BCG dataset of Colditz to demonstrate correct methodology and computed the results using PROC MIXED in SAS. In trying to duplicate the results presented in this paper, I have discovered that I can reproduce certain items with lmer but not others. I was hoping that someone might point out how I could correctly program R code to arrive at the correct solution.
<snip> There appears to be a tacit assertion here that the results from PROC MIXED in The-Package-That-Must-Not-Be-Named are the correct results. This assertion is very likely to bring the wrath of Doug Bates down upon your head. An outcome to be devoutly avoided! :-) cheers, Rolf Turner ###################################################################### Attention: This e-mail message is privileged and confidential. If you are not the intended recipient please delete the message and notify the sender. Any views or opinions presented are solely those of the author. This e-mail has been scanned and cleared by MailMarshal www.marshalsoftware.com ######################################################################