The Impact of Questionnaire Mode on Estimates of Health Insurance Coverage and Vaccines for Children Program Eligibility in the National Immunization Survey

Thursday, May 12, 2022

Rachel Francis

NORC at the University of Chicago
Zachary H. Seeskin

NORC at the University of Chicago
Amie Conley

NORC at the University of Chicago
Laurie D. Elam-Evans

National Center for Immunization and Respiratory Diseases
Chalanda Smith

National Center for Immunization and Respiratory Diseases
Holly A. Hill

National Center for Immunization and Respiratory Diseases
Michael Chen

National Center for Immunization and Respiratory Diseases, CDC

The National Immunization Surveys (NIS) monitor vaccination coverage and access in the United States for children ages 19-35 months, adolescents ages 13-17 years, and for influenza vaccination, children ages 6 months-17 years. The NIS currently operates as a random digit dialing (RDD) mobile telephone survey. In 2021, a pilot was conducted to assess the viability of using an address-based sampling (ABS) approach with multiple modes of data collection, including a self-administered web survey and self-administered paper-and-pencil interviewing (PAPI) in addition to telephone. We compared estimates of health insurance coverage and eligibility for the Vaccines for Children (VFC) program from the RDD and ABS versions of the NIS questionnaires and found estimates from the NIS-ABS Pilot indicated higher rates of private insurance coverage and lower rates of coverage with Medicaid and other public insurance types compared to the NIS-RDD. Additionally, estimates of VFC eligibility were higher in the NIS-RDD compared with the NIS-ABS Pilot version. These differences appear to be attributable to differences in both the questionnaires and the characteristics of respondents by survey mode.