Many parametric tests assume an underlying normal distribution for the population. If your data do not meet this assumption, you might prefer to use a nonparametric analysis.
Base SAS software provides several tests for normality in the UNIVARIATE procedure. Depending on your sample size, PROC UNIVARIATE performs the Kolmogorov-Smirnov, Shapiro-Wilk, Anderson-Darling, and Cramér-von Mises tests. For more information, see the chapter "The UNIVARIATE Procedure" in the Base SAS Procedures Guide.