Definition
VACOPV1STIM indicates whether the child received the first polio dose just after birth (as opposed to later).
If the child received the first polio dose immediately after birth, that indicates the child received the birth dose of polio (OPV 0), which can be found in VACOPV0. If VACOPV0 is not available in a particular sample, users may wish to recode children from VACOPV1 who received the first dose just after birth as having received VACOPV0 (the birth dose of polio vaccine) rather than VACOPV1 (the first dose of polio vaccine, administered later).