What about using Excel? I use it to create block randomization for
animal studies. Put the labels to identify the animal groups in one
column. Create a suitable size block, then copy it several times so that
you have a total number greater than what you'll actually need. Fill the
next column with the formula "=rand()". That will put a random number
next to each animal label. Then copy that column and use 'paste special'
to convert the random number function to a fixed value. Finally sort
each block separately by the random number. Now you have a bunch of
blocks with each group represented in random order. Just work your way
down that list in order. If I understood your question correctly, each
of your blocks would represent a different weight range.
--
Claudio M. Martin, MD, MSc, FRCPC _/_/ _/_/ _/_/_/_/_/ _/_/
Assistant Professor, Medicine/Physiology _/ _/ _/ _/
University of Western Ontario _/ _/ _/ _/
519-667-6786 FAX 519-667-6748 _/_/ _/_/ _/ _/_/
Mail: Critical Care Trauma Centre, London Health Sciences Centre
Victoria Campus, 375 South Street, London, Ontario, Canada N6A 4G5
URLs: [Critical Care] http://critcare.lhsc.on.ca
[Academic Health Sciences Network] http://ahsn.lhsc.on.ca