Comparing two values in a column

[Anita_n]

@Reeza I tried that, it's similar to what @ballardw  first posted. You have N=8. N should be =4 because I have 4 patients. In proc ttest for example there is a way to pair two columns. For a example using your tranposed data set 'wide'. Is there something like that in proc means or any other procedure to calculate the mean, min, max etc?

proc ttest data= wide plots=none;
paired visit_1*visit_2;
ods output ttests=ttest_1;
ods output Statistics=Stat_1;
run;

[Reeza]

Only the first proc means has N=8 the remaining have other N's that reflect different summaries.
All of the proc means are also saving the output to a data set.
Please review the code in detail.

[Anita_n]

@PaigeMiller @Reeza @ballardw : I finally solved it this way 

proc sql;
create table test1 as select patid as patid1, visit as visit1 , var as var1 from test where visit=1;

create table test2 as select patid as patid2, visit as visit2 , var as var2 from test where visit=2;

create table test3 as select a.*, b.*  from test1 as a right join test2 as b on a.patid1=b.patid2;

quit;

proc means data=test3 n mean std min max nmiss;
var  var1;
run;

and as result :

That is what I wanted, thanks for the help 

[andreas_lds]

or just

proc sql;
   select n(a.var) as n, mean(a.var) as mean, std(a.var) as std /*  insert other stats */
      from work.test a
         join work.test b on a.patid = b.patid and a.visit = 1 and b.visit = 2
   ;
quit;

[Reeza]

Which is identical to the last proc means in my example.