Codes and Frequencies
For sample children under 6 years old who reported any information regarding their polio vaccine(s) and who received at least four polio vaccines, IMAPOLAGE4 reports the person's age when he or she received the fourth polio vaccine.
Users are strongly encouraged to visit the Universe tab for more information on changes in the universe across surveyed years.
- 1991: Sample persons under age 6 who reported any information on polio vaccines and received four or more polio vaccines.
- 1991 : SAMPWEIGHT