Let's not reinvent the wheel 🙂    SAS provides functionality to handle categorical variables, depending on your procedure.  Or you can use the methods here: http://blogs.sas.com/content/iml/2016/02/22/create-dummy-variables-in-sas.html   At the bottom of this page there are three other links with ways to create dummy variables https://communities.sas.com/t5/SAS-Communities-Library/How-to-create-dummy-variables-Categorical-Variables/ta-p/308484 ... View more

Yes. In SAS procedures the output column for the p-values will be labeled as "Pr > statistic" where statistic might be "t" for a t-statistic, "F"  for an F statistic, "ChiSq" for a chi-square statistic, and so on.   Small values in that column indicate a  rejection of the null hypothesis at the specified significance level. ... View more

With surveyfreq if you use the where clause you remove some information and really wouldn't want to have a table statement with   tables age*sex.   Are perhaps looking to do domain analysis of age? You may want to look at SURVEYMEANS and use a Domain Sex statement. ... View more