Documentation Example 1 for PROC SEQTEST
/****************************************************************/
/* S A S S A M P L E L I B R A R Y */
/* */
/* NAME: SEQTEX1 */
/* TITLE: Documentation Example 1 for PROC SEQTEST */
/* PRODUCT: STAT */
/* SYSTEM: ALL */
/* KEYS: group sequential test */
/* PROCS: SEQDESIGN, SEQTEST, GENMOD */
/* DATA: */
/* */
/* SUPPORT: Yang Yuan UPDATE: Aug 21, 2007 */
/* REF: PROC SEQTEST, EXAMPLE 1 */
/* MISC: */
/****************************************************************/
ods graphics on;
proc seqdesign altref=0.15
boundaryscale=mle
;
OBrienFleming: design method=obf
nstages=4
alt=upper
stop=both
alpha=0.025
;
samplesize model=twosamplefreq(nullprop=0.6 test=prop);
ods output Boundary=Bnd_Count;
run;
data count;
do j=1 to 215;
Trt=0;
Resp= ranbin( 312511, 1, 0.55);
output;
Trt=1;
Resp= ranbin( 312511, 1, 0.74);
output;
end;
run;
data count_1;
set count;
if (j <= 54);
run;
data count_2;
set count;
if (j <= 108);
run;
proc print data=count(obs=10);
var Trt Resp;
title 'First 10 Obs in the Trial Data';
run;
proc genmod data=count_1;
model Resp= Trt;
ods output ParameterEstimates=Parms_Count1;
run;
data Parms_Count1;
set Parms_Count1;
if Parameter='Trt';
_Scale_='MLE';
_Stage_= 1;
keep _Scale_ _Stage_ Parameter Estimate StdErr;
run;
proc print data=Parms_Count1;
title 'Statistics Computed at Stage 1';
run;
proc seqtest Boundary=Bnd_Count
Parms(Testvar=Trt)=Parms_Count1
infoadj=none
errspendmin=0.001
boundaryscale=mle
errspend
plots=errspend
;
ods output Test=Test_Count1;
run;
proc genmod data=Count_2;
model Resp= Trt;
ods output ParameterEstimates=Parms_Count2;
run;
data Parms_Count2;
set Parms_Count2;
if Parameter='Trt';
_Scale_='MLE';
_Stage_= 2;
keep _Scale_ _Stage_ Parameter Estimate StdErr;
run;
proc print data=Parms_Count2;
title 'Statistics Computed at Stage 2';
run;
proc seqtest Boundary=Test_Count1
Parms(Testvar=Trt)=Parms_Count2
infoadj=none
boundaryscale=mle
;
ods output Test=Test_Count2;
run;