/*sibling data for McNemar test */

data siblings;
input older younger count ;
datalines;
 1 1 15
 1 2 7
 2 1 5
 2 2 10
;
run;

/* normal approximation and exact McNemar test */
proc freq data=siblings; 
weight count;
tables older*younger / agree;
exact mcnem;
run;

/* comparison with approach for independent data*/
data notsiblings;
input age $ time $ count ;
datalines;
 older "<1min" 22
 older ">1min" 15
 younger "<1min" 20
 younger ">1min" 17
;
proc freq data=notsiblings order=data;
weight count;
tables age*time /chisq riskdiff;
run;