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About the National Data
Baseline: 1.3 percent of children born in 2015 had received 0 doses of recommended vaccinations by their 2nd birthday
Target: 1.3 percent
Maintain the baseline
The National Immunization Survey (NIS) uses a quarterly, random-digit-dialed sample of telephone numbers to reach households with children aged 19–35 months in the 50 states and selected local areas and territories, followed by a mail survey sent to the children's vaccination providers to collect vaccination information. Data are weighted to represent the population of children aged 19–35 months (or of children born during a calendar year), with adjustments for households with multiple telephone lines and mixed telephone use (landline and cellular), household nonresponse, and exclusion of households without telephone service. Beginning in 2011, surveys include landline and cellular telephone households. In 2018, surveys only included cellular telephone households. This measure tracks the proportion of children born during a calendar year receiving zero doses of any recommended vaccine by age two years. The Kaplan-Meier method will be used to account for censoring of vaccination status among children whose vaccination history is unknown after age 19-23 months.