Getting Started Example for PROC SEQTEST
/****************************************************************/
/* S A S S A M P L E L I B R A R Y */
/* */
/* NAME: SEQTGS */
/* TITLE: Getting Started Example for PROC SEQTEST */
/* PRODUCT: STAT */
/* SYSTEM: ALL */
/* KEYS: group sequential test */
/* PROCS: SEQDESIGN, SEQTEST, REG */
/* DATA: */
/* */
/* SUPPORT: Yang Yuan UPDATE: Aug 21, 2007 */
/* REF: PROC SEQTEST, GETTING STARTED EXAMPLE */
/* MISC: */
/****************************************************************/
ods graphics on;
proc seqdesign altref=-10.0;
TwoSidedOBrienFleming: design nstages=4
method=obf
;
samplesize model=twosamplemean(stddev=20);
ods output Boundary=Bnd_LDL;
run;
ods graphics off;
data ldl;
do j=1 to 86;
Trt=0; Ldl= 20*rannor(960303);
Ldl= int( 100*Ldl) / 100; output;
Trt=1; Ldl= -7.8 + 20*rannor(960303);
Ldl= int( 100*Ldl) / 100; output;
end;
run;
data ldl_1;
set ldl;
if j <= 22;
run;
data ldl_2;
set ldl;
if j <= 43;
run;
data ldl_3;
set ldl;
if j <= 65;
run;
proc print data=ldl_1(obs=10);
var Trt Ldl;
title 'First 10 Obs in the Trial Data';
run;
proc reg data=LDL_1;
model Ldl=Trt;
ods output ParameterEstimates=Parms_LDL1;
run;
data Parms_LDL1;
set Parms_LDL1;
if Variable='Trt';
_Scale_='MLE';
_Stage_= 1;
keep _Scale_ _Stage_ Variable Estimate StdErr;
run;
proc print data=Parms_LDL1;
title 'Statistics Computed at Stage 1';
run;
ods graphics on;
proc seqtest Boundary=Bnd_LDL
Parms(Testvar=Trt)=Parms_LDL1
infoadj=prop
;
ods output Test=Test_LDL1;
run;
ods graphics off;
proc reg data=LDL_2;
model Ldl=Trt;
ods output ParameterEstimates=Parms_LDL2;
run;
data Parms_LDL2;
set Parms_LDL2;
if Variable='Trt';
_Scale_='MLE';
_Stage_= 2;
keep _Scale_ _Stage_ Variable Estimate StdErr;
run;
proc print data=Parms_LDL2;
title 'Statistics Computed at Stage 2';
run;
proc seqtest Boundary=Test_LDL1
Parms(Testvar=Trt)=Parms_LDL2
infoadj=prop
;
ods output Test=Test_LDL2;
run;
proc reg data=LDL_3;
model Ldl=Trt;
ods output ParameterEstimates=Parms_LDL3;
run;
data Parms_LDL3;
set Parms_LDL3;
if Variable='Trt';
_Scale_='MLE';
_Stage_= 3;
keep _Scale_ _Stage_ Variable Estimate StdErr;
run;
proc print data=Parms_LDL3;
title 'Statistics Computed at Stage 3';
run;
ods graphics on;
proc seqtest Boundary=Test_LDL2
Parms(Testvar=Trt)=Parms_LDL3
infoadj=prop
;
ods output Test=Test_LDL3;
run;
ods graphics off;