How are data for the NIS collected?
We use random-digit-dialing to find households with children aged 19 to 35 months. We ask parents or guardians to tell us the vaccines-with dates-that appear on the child’s “shot card” kept in the home, and we also collect demographic and socioeconomic information. At the end of the interview, we ask for permission to contact the child’s vaccination providers. Providers are then contacted by mail to verify each child’s vaccinations.
