/* pain1.sas (2018 version) */
title 'Multivariate repeated measures analysis of the pain data';

/* Read data from an old .xls spreadsheet */
proc import datafile="/folders/myfolders/441s18/Lecture/Pain.xls" 
            out=ouch0 dbms=xls replace;
            getnames=yes;
proc print;

/*           Dose 1         Dose 2         Dose 3
             ------         -----          ------
Drug 1     Drug1Dose1     Drug1Dose2     Drug1Dose3
Drug 2     Drug2Dose1     Drug2Dose2     Drug2Dose3   */

/* Computing sum and contrast variables in the data step */
data ouch1;
     set ouch0;
     /* Pairwise differences */
     d12 = Drug1Dose1-Drug1Dose2; d13 = Drug1Dose1-Drug1Dose3; 
     d14 = Drug1Dose1-Drug2Dose1; d15 = Drug1Dose1-Drug2Dose2; 
     d16 = Drug1Dose1-Drug2Dose3; 
     d23 = Drug1Dose2-Drug1Dose3; d24 = Drug1Dose2-Drug2Dose1; 
     d25 = Drug1Dose2-Drug2Dose2; d26 = Drug1Dose2-Drug2Dose3;
     d34 = Drug1Dose3-Drug2Dose1; d35 = Drug1Dose3-Drug2Dose2; 
     d36 = Drug1Dose3-Drug2Dose3;
     d45 = Drug2Dose1-Drug2Dose2; d46 = Drug2Dose1-Drug2Dose3; 
     d56 = Drug2Dose2-Drug2Dose3;
     /* Marginal means and interactions */
     Drug1 = mean(of Drug1Dose1--Drug1Dose3); 
     Drug2 = mean(of Drug2Dose1--Drug2Dose3);
     Dose1 = (Drug1Dose1+Drug2Dose1)/2; 
     Dose2 = (Drug1Dose2+Drug2Dose2)/2; 
     Dose3 = (Drug1Dose3+Drug2Dose3)/2; 
     Drugdiff = drug1-drug2;
     doseD12 = dose1-dose2; doseD13 = dose1-dose3; 
     doseD23 = dose2-dose3;
     DrugEffect1 = Drug1Dose1-Drug2Dose1;
     DrugEffect2 = Drug1Dose2-Drug2Dose2;
     DrugEffect3 = Drug1Dose3-Drug2Dose3;
     label DrugEffect1 = 'Drug effect for dose 1'
           DrugEffect2 = 'Drug effect for dose 2'
           DrugEffect3 = 'Drug effect for dose 3';
     int1 = DrugEffect1-DrugEffect2; 
     int2 = DrugEffect1-DrugEffect3;
     int3 = DrugEffect2-DrugEffect3;

proc means data=ouch1  n mean stddev maxdec=3;
     var Drug1Dose1 -- Drug2Dose3   
         Drug1 Drug2 
         Dose1-Dose3 
         DrugEffect1-DrugEffect3;
run;

/* Test for overall differences, main effects and interaction.
   Just look at the multivariate output.  */
ods select MultStat (persist);

proc reg data=ouch1;
     title2 'Overall test';
     model d12-d16 = ;
     Overall: mtest intercept = 0;
run;

proc reg data=ouch1;
     title2 'Main Effect of Drug';
     model drugdiff = ;
     Drug: mtest intercept = 0;
     /* Could have used test or just looked at the t statistic. */
run;

proc reg;
     title2 'Main Effect of Dose Level';
     model dosed12 dosed13 = ;
     Dose: mtest intercept = 0;
run;

proc reg data=ouch1;
     title2 'Drug by Dose Interaction';
     model int1 int2 = ;
     Drug_by_Dose: mtest intercept = 0;
run;

/* Follow up, including tests of pairwise difference
   even though the overall test was not significant. */

ods select all; /* Turning off the selection */

proc means data=ouch1 n mean t probt;
     title2 'Follow up with matched t-tests';
     var d12 -- d56        
         dosed12--dosed23  
         int1-int3 ;

/* Specify transformations of response variables within proc reg 

             Dose 1         Dose 2         Dose 3
             ------         -----          ------
Drug 1     Drug1Dose1     Drug1Dose2     Drug1Dose3
Drug 2     Drug2Dose1     Drug2Dose2     Drug2Dose3   */


/* Strangely, after the first time I use ods select in a job, it only
   seems to work when I precede it with quit. ods is a little flaky 
   with SAS University Edition; maybe that's the reason. */

quit; ods select MultStat;
proc reg data=ouch0 plots=none;
     title2 'Specify new response variables within proc reg';
     model Drug1Dose1 -- Drug2Dose3 = ;
     Overall: mtest intercept = 0, 
              Drug1Dose1-Drug1Dose2, Drug1Dose1-Drug1Dose3,
              Drug1Dose1-Drug2Dose1, Drug1Dose1-Drug2Dose2,
              Drug1Dose1-Drug2Dose3;
     Drug: mtest intercept = 0, 
           Drug1Dose1+Drug1Dose2+Drug1Dose3  
         - Drug2Dose1-Drug2Dose2-Drug2Dose3;
     Dose: mtest intercept = 0, 
           Drug1Dose1+Drug2Dose1 - Drug1Dose2-Drug2Dose2,
           Drug1Dose2+Drug2Dose2 - Drug1Dose3-Drug2Dose3;
     Interaction: mtest intercept = 0, 
                  Drug1Dose1-Drug2Dose1 - Drug1Dose2+Drug2Dose2,
                  Drug1Dose1-Drug2Dose1 - Drug1Dose3+Drug2Dose3;
run;

quit; ods select  MultStat GLM.Repeated.WithinSubject.ModelANOVA;
proc glm data=ouch0;
     title2 'Two-factor within cases the easy way';
     model Drug1Dose1--Drug2Dose3 = ;
     repeated Drug 2, Dosage 3 / short summary;
     /* Factor on the right changes fastest (like numbers) */
run;

quit; ods select  MultStat GLM.Repeated.WithinSubject.ModelANOVA;
proc glm data=ouch0;
     title2 'Overall test the easy way';
     model Drug1Dose1--Drug2Dose3 = ;
     repeated treatment / short summary;
run;