有了交互作用,计算OR值的时候就必须要考虑到交互变量是在什么水平,比如在算A vs P的OR值在sex = F 的水平上,SAS code如下:
ods output parameterEstimates=estimate ContrastEstimate=OR;
proc logistic data=Neuralgia;
class Treatment Sex;
model Pain= Treatment sex treatment*sex;
contrast 'A vs P at gender = F' treatment 2 1 treatment*sex -2 -1 /estimate=exp;
run;
ods output close;(例子为引用)