FILENAME goptions URL "http://192.38.117.59/~linearpredictors/datafiles/goptions.sas";
%include goptions;

FILENAME url URL "http://192.38.117.59/~linearpredictors/datafiles/readSurgery.sas";
%include url;

DATA surgery;
SET surgery; WHERE surgtype IN (2,3);
RUN;

/* confidence limits for discrepancies between complication frequencies */

/* OR, corresponding to link=logit */
    
PROC GENMOD DESCENDING DATA=surgery;
    CLASS surgtype;
    MODEL complication = surgtype / dist=binomial link=logit;
    estimate 'OR, abdominal vs gynecolocical' surgtype 1 -1 / exp;
RUN;

/* Relative risk, corresponding to link=log */
    
PROC GENMOD DESCENDING DATA=surgery;
    CLASS surgtype;
    MODEL complication = surgtype / dist=binomial link=log;
    estimate 'RR, abdominal vs gynecolocical' surgtype 1 -1 / exp;
RUN;

/* Difference, corresponding to link=identity */
    
PROC GENMOD DESCENDING DATA=surgery;
    CLASS surgtype;
    MODEL complication = surgtype / dist=binomial link=identity;
    estimate 'difference, abdominal vs gynecolocical' surgtype 1 -1;
RUN;