{"id":658,"date":"2016-01-21T17:36:32","date_gmt":"2016-01-21T17:36:32","guid":{"rendered":"https:\/\/www.vdh.virginia.gov\/epidemiology\/?page_id=658"},"modified":"2025-08-25T12:56:39","modified_gmt":"2025-08-25T16:56:39","slug":"nis","status":"publish","type":"page","link":"https:\/\/www.vdh.virginia.gov\/immunization\/datamanagement\/nis\/","title":{"rendered":"National Immunization Survey (NIS)"},"content":{"rendered":"
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Beginning in 1994, NIS has collected information about the immunization coverage of children 19 months to 35 months of age.\u00a0 Beginning in 2008, information has also been collected about adolescents, 13-17 years of age, across the United States.\u00a0 Data are used to monitor immunization coverage in the preschool population in 78 non-overlapping geographic areas.\u00a0 The survey is a collaborative effort between CDC, the National Center of Health Statistics and the\u00a0 National Center for Immunization and Respiratory Diseases.\u00a0 More information regarding the NIS can be found at\u00a0https:\/\/www.cdc.gov\/nis\/about\/?CDC_AAref_Val=https:\/\/www.cdc.gov\/vaccines\/imz-managers\/nis\/index.html<\/a>.<\/p>\n

How accurate and reliable are these numbers?<\/strong><\/h3>\n

The NIS is accurate and reliable.\u00a0 The accuracy is supported by the agreement between the NIS, a telephone survey, and the National Health Interview survey, a nationally representative, household, door-to-door survey. The reliability of the NIS is reflected in the size of the confidence interval; it is more reliable at the national level than at the state or urban level.\u00a0 This is because the number of interviews overall is so much larger than the number of interviews for any state.<\/p>\n

Why do the NIS vaccination coverage rates differ from other surveys?<\/strong><\/h3>\n

There are many possible reasons why the rates could differ, because the systems use:<\/p>\n