/* Data Analysis Project 1 */
/* Response is "severity of illness" on a 7 point scale.   
It measures severity of schizophrenia illness in patients.  
*/
OPTIONS NOCENTER LINESIZE=81 PAGESIZE=66;
TITLE1 'Schizophrenia data';
DATA ONE; 
INFILE 'D:\mystuff\RMbook\rmnotes\comps\dap1.dat';
*Alter file name to point to your copy of the data set;
INPUT ID severity WEEK DRUG SEX ;
 
/* The coding for the variables is as follows:
   ID     = subject ID number
   severity = IMPS79 = overall disease severity (1=normal, ..., 7=among the most extremely ill)
   WEEK   = 0,1,2,3,4,5,6 (most of the obs. are at weeks 0,1,3, and 6)
   DRUG     0=placebo  1=drug (chlorpromazine, fluphenazine, or thioridazine)
   SEX      0=female   1=male
*/

/* calculate the maximum value of WEEK for each subject
   (suppress the printing of the output for this procedure) */
PROC MEANS NOPRINT; CLASS ID; VAR WEEK; OUTPUT OUT=TWO MAX=MAXWEEK;
RUN;

/* determine if a subject has data at WEEK 6
   DROPOUT  = 0 (for completers) or = 1 (for dropouts) */
DATA THREE; SET TWO;
     DROPOUT=0;
     IF MAXWEEK LT 6 THEN DROPOUT=1;

/* dataset with all subjects (adding the DROPOUT variable) */
DATA FOUR; MERGE ONE THREE; BY ID;
proc sort;
by dropout id week;
run;