*/ Thanks Dr.John Petkau from UBC Stats Department for the data./*

data exacerb;
infile 'C:\Documents and Settings\Administrator\Desktop\QIF\exacerb.txt';
input datnum id time edss relap dose locat age sex dur visit @@;
t1 = time;
t2 = time*time;
run;
proc print data = exacerb;
var t2;
run;
proc genmod data=exacerb descending;
class id; 
model relap = dose t1 t2 dur / dist=bin link=logit;
repeated subject=id / type=exch corrw covb modelse;
run;
%include 'C:\Documents and Settings\Administrator\Desktop\QIF\QIFv01.sas';
%qif(data=exacerb, yvar=relap, xvar=dose t1 t2 dur, id=id, dist=bin, corr=exch, print=Y, 
     outpar=par2, outqif=qif2, outcov=cov2, outres=binres);