In most of the statistical tests, you need check assumption of normality. There is a test called Shapiro-Wilk W test that can be used to check normal distribution. If the p-value is greater than .05, it means we cannot reject the null hypothesis that a variable is normally distributed.
SAS Macro for Normality
/*************************************************
*input = dataset to check;
*vars = Specify variable(s) for which you want to check normality;
*output = dataset to output with normality status;
**************************************************/
ods output TestsForNormality = Normal;
proc univariate data = &input normal;
var &vars;
run;
ods output close;
data &output;
set Normal ( where = (Test = 'Shapiro-Wilk'));
if pValue > 0.05 then Status ="Normal";
else Status = "Non-normal";
drop TestLab Stat pType pSign;
run;
%mend;
%normal(input=test, vars=X1 X2, output=Normality);
proc univariate data = &input normal;
var &vars;
run;
ods output close;
data &output;
set Normal ( where = (Test = 'Shapiro-Wilk'));
if pValue > 0.05 then Status ="Normal";
else Status = "Non-normal";
drop TestLab Stat pType pSign;
run;
%mend;
%normal(input=test, vars=X1 X2, output=Normality);
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