# The Summary Statistics
The AAAstudy data is characterized with an equal spaced measurement of 6 months. The measurements of the subjects is unbalance which may have been due to drop out. The summary statistics is explored and compared using the Analysis of Increments and the Analysis of Area under the Curve. The ttest procedure in SAS is applied to test the evolution of the AAA measures. The test result suggest an evolution in the measurement among the subject over the study period.
```{}
proc sort data = LDA.renamedLDA; /*Analysis of Increments*/
by patient;
run;
proc print data= LDA.renamedLDA ; run;
data LDA.summary;
set LDA.renamedLDA;
by patient;
retain M1;
if FIRST.patient then do;
M1= D_max_Abdominaal__mm_; end;
if LAST.patient then do;
M2=D_max_Abdominaal__mm_;
LDA_ch = M2 - M1;
output;
end;
run;
proc print data= LDA.summary noobs; var patient M1 M2 LDA_ch; run;
proc ttest data=LDA.summary;
var LDA_ch;
run;
```
