KEYWORDS:
Provider record check, verbal consent, provider vaccination data

BACKGROUND:
The National Immunization Survey (NIS) measures vaccination coverage among children aged 19-35 months in the U.S., the 50 states, and 28 urban areas. A random-digit-dialing telephone screening survey is used to identify households with age eligible children. During the household interview, parents/guardians are asked for consent to contact children’s vaccination providers. In the provider survey, questionnaires are mailed to vaccination providers to obtain the children’s vaccination histories. The NIS is sponsored by the National Immunization Program (NIP) and the National Center for Health Statistics (NCHS)and conducted by Abt Associates, Inc.

OBJECTIVE(S):
To describe the steps involved in obtaining provider vaccination data and show how the percentage of children with provider data has increased considerably from earlier time periods.

METHOD(S):
Key NIS provider survey indicators were examined for 1999 and 2000. Key statistics include the percentage of children with consent, the percentage of children with complete provider name and address information, and the percentage of providers that respond with vaccination histories.

RESULT(S):
For Q4/1999-Q3/2000 84% of parents/guardians gave consent to contact vaccination providers. Among children for whom consent was obtained, we mailed provider questionnaires to the 93% of providers with usable address information. More than three-fourths of the questionnaires mailed were returned with vaccination history information. In 1995 51% of children had provider-reported vaccination data. By Q4/1999-Q3/2000 this had risen to 67%.

CONCLUSIONS(S):
Procedures were developed and implemented to: reduce the percentage of children without consent to contact providers; increase the accuracy of identification of provider names and addresses; and follow-up with providers to have completed questionnaires returned. These procedures were effective in increasing the percentage of children with provider-reported vaccination data in the NIS.

LEARNING OBJECTIVES:
To describe methods that can be used in an immunization survey to increase the percentage of children with provider-reported vaccination data.