/****************************************************************/ 
 /*          S A S   Macros                                      */ 
 /*                                                              */ 
 /*    NAME: mPlan                                               */ 
 /*   TITLE: Randomisation Schedule generation                   */ 
 /*  AUTHOR: Jimmy Xiao (jimmy.xiao@ClinStReport.com)            */ 
 /*  SYSTEM: SAS                                                 */ 
 /*    DATE: Jul, 2004                                           */ 
 /*   PROCS: Proc Plan                                           */ 
 /*    MISC:                                                     */ 
 /*                                                              */ 
 /****************************************************************/ 
%Macro mPlan(group=2,Ratio=2:1,block=6,total=144,outset=out,seed=9999);
%if %length(%cmpres(&group))=0 %then %let group=2;
%if %length(%cmpres(&ratio))=0 %then %let group=2:1;
%if %length(%cmpres(&block))=0 %then %let block=6;
%if %length(%cmpres(&total))=0 %then %let group=144;
%if %length(%cmpres(&OutSet))=0 %then %let OutSet=out;
%if %length(%cmpres(&seed))=0 %then %let seed=9999;


%let tRatio=0;
%do i=1 %to &group;
	%let Ratio&i=%scan(&Ratio,&i,:);
	%let tRatio=%eval(&tRatio+&&Ratio&i);
%end;
%if %sysfunc(mod(&block,&tRatio)) ne 0 %then %do;
	%put ERROR: Either Parameter BLOCK or RATIO is assigned wrong,macro Stopped!;
	%goto TheEnd;
%end;
proc plan seed=&seed ;
   factors Serial=%eval(&total/&block) 
		ordered block=&block ordered / noprint;
   treatments treat=█
   output out=&outset(drop=block serial) treat 
	cvals=(	%do i=1 %to %eval(&block/&tRatio);
				%do j=1 %to &group; 
					%do k=1 %to &&ratio&j; "%sysfunc(byte(&j+64))" %end ;
				%end;
			%end;);;
run; 

data &outset;
	format patient best.;
	set &outset;
	patient=_N_;
run;

%theEnd:;

%mend;

/* Sample Usage */
/* To generate 144 randomization codes for 1:1 designed two treatment arms trial */
%mPlan(group=2,Ratio=1:1,block=4,total=144,outset=out1,seed=9999);