This section discusses some considerations of managing tables with the SAS System. If you are already familiar with the FREQ procedure, you may want to skip this section.
Many times, categorical data are presented to the researcher in the form of tables, and other times, they are presented in the form of case record data. SAS procedures can handle either type of data. In addition, many categorical data have ordered categories, so that the order of the levels of the rows and columns takes on special meaning. There are numerous ways that you can specify a particular order to SAS procedures.
Consider the following SAS DATA step that inputs the data displayed in Table 1.1.
data respire; input treat $ outcome ...