Data from smart design
id: id of subject
status : 1-death, 2-response for second randomization, 0-censoring
A0 : treament at first randomization
A1 : treament at second randomization
At.f : treament given at record (A0 or A1)
TR : time of response
sex : 0-males, 1-females
consent: 1 if agrees to 2nd randomization, censored if not
R: 1 if response
trt1: A0
trt2: A1