*Program 11-2 Testing for numeric and character missing values
 (without the missing function);
data test_miss;
   set learn.blood;
   if Gender = ' ' then MissGender + 1;
   if WBC = . then MissWBC + 1;
   if RBC = . then MissWBC + 1;
   if Chol lt 200 and Chol ne . then Level = 'Low ';
   else if Chol ge 200 then Level = 'High';
run;

*Program 11-3 Demonstrating the MISSING function;
data test_miss;
   set learn.blood;
   if missing(Gender) then MissGender + 1;
   if missing(WBC) then MissWBC + 1;
   if missing(RBC) then MissWBC + 1;
   if Chol lt 200 and not missing(Chol) then 
      Level = 'Low ';
   else if Chol ge 200 then Level = 'High';
run;