3rd course treatment.chemotherapy:Prid:Pt:Subsequent cancer Rx:Nom
3rd course treatment.chemotherapy:prid:pt:subsequent cancer rx:nom
3rd course treatment.chemotherapy:Presence or Identity:To identify measures at a point in time:Subsequent cancer Rx:Nominal
3rd course treatment.chemotherapy:presence or identity:to identify measures at a point in time:subsequent cancer rx:nominal