Definition
For children born in the 3 to 5 years before the survey, VACPOLIO4 indicates whether the child has received the fourth in a series of polio vaccinations, either an oral polio vaccine (OPV) or an inactivated polio vaccine (IPV).
The polio vaccination primary series usually consists of a birth dose, 3 additional administrations, and a single inactivated polio dose. The complementary variables VACOPV0 (H0), VACOPV1 (H4), VACOPV2 (H6), and VACOPV3 (H8), and VACIPV1 (H60) report the birth, first, second, third, and inactivated polio administrations, respectively.
VACPOLIO4 uses composite coding, with a first digit of 2 indicating the child has been vaccinated and the second digit indicating the source of information (a dated entry on the vaccination card, an undated mark on the vaccination card, or the mother's report).