At A Glance
Noteworthy Characteristics
- Contains information on breastfeeding patterns for children 6 months to 3 years.
- Provides state-specific information and information from select local areas.
Website
https://www.cdc.gov/vaccines/imz-managers/nis/index.html
Purpose
To collect data on vaccinations and breastfeeding for children in the United States (U.S.).
Target Population
Children ages 19 through 35 months living in the U.S. NIS covers all 50 states, the District of Columbia, the U.S Virgin Islands, Guam, Puerto Rico, and other selected major urban areas.
Conducted
Began in 1994. Conducted annually, with release of annual data within about nine months after end of the data collection year. Check for the most current data and data collection instruments
Sponsor
National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, U.S. Department of Health and Human Services.
Special Note(s)
Household telephone survey with mailed survey of children’s vaccination providers.
Contact:
lxe1@cdc.gov
Public-use files are released within 9 months after the end of each calendar year of data collection.
Learn more about vaccination coverage estimates and related NIS information.
Learn more about breastfeeding practices based on NIS and other sources.
Sampling
Sample Design
Cross-sectional survey.
Random, multi-stage, stratified, probability sampling. Oversampling of major urban areas. Learn more
about the sampling design.
Random digit dialed telephone survey. Cellular telephone sample was added in 2011.
Sample Size
Approximately 24,900 children in 2014.
Key Variables
Demographic
| Name | Methods of Assessment |
|---|---|
| Age of child | Interview/questionnaire (maternal) |
| Family income | Interview/questionnaire (maternal) |
| Maternal age, education | Interview/questionnaire (maternal) |
| Maternal race/ethnicity (restricted use only) | Interview/questionnaire (maternal) |
| Maternal marital status | Interview/questionnaire (maternal) |
| Participation in the Special Supplemental Program for Women, Infants, and Children (WIC) | Interview/questionnaire (maternal) |
| Sex of child | Interview/questionnaire (maternal) |
| Race/ethnicity of child | Interview/questionnaire (maternal) |
| Child's birth order | Interview/questionnaire (maternal) |
Diet-Related
| Name | Methods of Assessment |
|---|---|
| Age at which child was no longer breastfeed | Interview/questionnaire (maternal) |
| Age at which child was no longer exclusively breastfed | Interview/questionnaire (maternal) |
| Breastfeeding | Interview/questionnaire (maternal) |
Geocode/Linkage
| Name | Methods of Assessment |
|---|---|
| State, selected city and county areas | N/A |
Data Access and Cost
Data Availability
Download data from the National Immunization Survey website.
Cost
Free of charge.
Special Note(s)
Learn more about accessing non-public NIS data files.
Geocode/Linkage
Geocode Variable(s)
State, selected city and county areas.
Existing Linkages
NIS data on immunization status have been linked to National Survey of Children with Special Health Care Needs data on insurance coverage using a unique household identifier and demographic characteristics. Learn more.
NIS data on immunization status also have been linked to National Survey of Children’s Health (NSCH) data on insurance coverage, recent preventive health care, and having a personal health care provider using a unique household identifier and demographic characteristics. Learn more.
Special Note(s)
Contact the National Center for Health Statistics Research Data Center to request access to collected data not included on public-use files.
Selected Publications
Diet-Related
Anstey EH, Chen J, Elam-Evans LD, Perrine CG. Racial and Geographic Differences in Breastfeeding — United States, 2011–2015. MMWR Morb Mortal Wkly Rep 2017;66:723–727.
Centers for Disease Control and Prevention. Breastfeeding trends and updated national health objectives for exclusive breastfeeding--United States, birth years 2000-2004. Morbidity and Mortality Weekly Report 2007;56(30):760-763.
Centers for Disease Control and Prevention. Progress in Increasing Breastfeeding and Reducing Racial/Ethnic Differences – United States 2000-2008 births. Morbidity and Mortality Weekly Report 2013;62(5):77-80
Centers for Disease Control and Prevention. Racial and ethnic differences in breastfeeding initiation and duration, by state --- National Immunization Survey, United States 2004—2008. Morbidity and Mortality Weekly Report 2010;59(11):327-334.
Centers for Disease Control and Prevention. Racial and socioeconomic disparities in breastfeeding--United States, 2004. Morbidity and Mortality Weekly Report 2006;55(12):335-339.
Joyce T and Reeder J. Changes in breastfeeding among WIC participants following implementation of the new food package. Matern Child Health J. 2015 Apr;19(4):868-76.
Methods
Centers for Disease Control and Prevention. NIS Survey Methods. Available at: https://www.cdc.gov/nchs/data/series/sr_01/sr01_061.pdf
Scanlon KS, Li R, Chen J, Grummer-Strawn L. Estimation of breastfeeding rates in the United States from the National Immunization Survey: the effect of adding a cellular telephone sample of respondents. Available at: http://www.cdc.gov/breastfeeding/data/nis_data/estimation-bf-rates.htm
Smith PJ, Hoaglin DC, Battaglia MP et al. Statistical Methodology of the National Immunization Survey, 1994-2002. Hyattsville (MD): National Center for Health Statistics. Vital and Health Statistics, Series 2, Number 138.
Smith PJ, Hoaglin DC, Rao JNK, Battaglia MP, Daniels D. Evaluation of adjustments for partial non-response bias in the U.S. National Immunization Survey. Journal of the Royal Statistical Society Series A. 2004;167(1):141-156.
Resources
Documentation/Codebook(s)
http://www.cdc.gov/vaccines/imz-managers/coverage/nis/child/index.html
