[R-sig-ME] Simulating Cluster RCTs

[Kevin E. Thorpe]

Hi All.

Apologies if this is the wrong list but after searching I have not found 
what I am looking for.

I would like (mainly for teaching) to be able to simulate cluster RCTs 
with continuous and binary outcomes. It appears to me that 
simulate.merMod in lme4 may be one way to do this. Unfortunately, I am a 
bit lost in the help file. For one thing, in the newparams argument, I 
have no idea what theta is.

Also, in the simulations I would like to be able to specify an ICC to 
control the clustering effect as well as the usual things (e.g. mean 
response in the control group, treatment effect, number of clusters and 
cluster sizes).

I would be most appreciative for any guidance or examples of this type 
of simulation, either with simulate.merMod or other approaches.

Thank you in advance for your time.

Kevin

-- 
Kevin E. Thorpe
Head of Biostatistics,  Applied Health Research Centre (AHRC)
Li Ka Shing Knowledge Institute of St. Michael's Hospital
Assistant Professor, Dalla Lana School of Public Health
University of Toronto
email: kevin.thorpe using utoronto.ca  Tel: 416.864.5776  Fax: 416.864.3016