st: Standardised age-sex adjusted prevalence rates

[Miranda Kim <mk@mrc.soton.ac.uk>]

In Stata 11, I would like to calculate age-sex-adjusted prevalence rates 
of a disease for cohorts from different countries that are standardised 
to a “standard population” which consists of all country cohorts put 
together.
At present my data is structured as follows
Variables (in columns): serial, age category, sex, disease(yes/no), 
country code
So each line corresponds to a distinct participant in a cohort 
identified by the country code.
At the moment I am looking at the stset and stsplit commands, but any 
advice on the most appropriate commands or helpful references for this 
would be much appreciated.
Many thanks,
Miranda

*
*   For searches and help try:
*   http://www.stata.com/help.cgi?search
*   http://www.stata.com/support/statalist/faq
*   http://www.ats.ucla.edu/stat/stata/