OPTIONS LINESIZE=88 PAGESIZE=53 NOCENTER NODATE NONUMBER NOFMTERR;
*********************************************************************;
* Project name: Learn to use EPIINFO                                 ;
*     Program Name             Date            Programmer            ;
TITLE "Sourse:hw15.sas        12/01/99              CJ"              ;
* Description:  Soil ingestion studies are conducted to estimated the;
*   quantity of soil casually ingested by children and adults        ;
*********************************************************************;
LIBNAME new "C:\temp";

DATA food(drop=al0);     SET new.food;
     rename al_f=al_fd f_pid=Fd_pid;

DATA fecal(drop=al0);
     SET new.fecal;
     rename al_f=al_fl;

DATA soil(keep=al0 pidx);
     SET new.soil;


proc sort data=food;  by pidx;
proc sort data=fecal; by pidx;
proc sort data=soil;  by pidx;


*************************************;
* Q1: estimates of soil ingestion on ;
* on each study day of each subject  ;
*************************************;

DATA d1;
  merge soil food fecal;  by pidx;


proc sort data=d1; by f_pid;

data d2;
  set d1;
  by f_pid;
  if first.f_pid;

data NEW.d3(keep=pidx f_pid digest);
   set d2;
   if al_fl gt al_fd then do;
    digest=(al_fl-al_fd)*1000/al0;
    end;
   label digest='estimates of*soil ingestion*on each study day*(mg)';

proc print;

proc print data=NEW.d3 split="*";
TITLE2 "Table1. Estaimates of soil ingestion on each study day of each subjects";
   ID pidx;

RUN;