When I read the way that this user is working with SAS, I took a look around support.sas.com to find examples to allow you to work with your own data. (Take a look at this.) If this example isn't quite right for you, plug in your own key words.
Let me know what other papers, SAS Samples and examples you find that help you analyze prevalence data. Have you developed your own analysis techniques? What are you doing with the data after analysis?