At A Glance

Noteworthy Characteristics

  • Provides information on prenatal and post-birth health status, prenatal health care.
  • Measured children’s height/length, weight, and middle upper arm circumference.
  • Includes data on breastfeeding and nutrition practices for very young children.
  • Includes measures of physical activity, sedentary behaviors, and sleep.
  • Includes information on participation in food assistance programs.
  • Provides geocode information to the zip code level.
  • Oversampled Chinese children, other Asian and Pacific Islander children, American Indian and Alaska Native children, twins, and low/very low birth weight children.



To collect data about the care and education, health, and development of children from birth through kindergarten entry.

Target Population

Children born in the United States (U.S.) in 2001.


Began in 2001. Conducted periodically (see Special Notes for additional details). Final year of collection was 2007.


National Center for Education Statistics, U.S. Department of Education. Learn more about the federal agencies that collaborated on the ECLS-B.

Special Note(s)

The Early Childhood Longitudinal Study (ECLS) program includes three longitudinal surveys that examine child development, school readiness, and early school experiences. In addition to the ECLS-B, the ECLS program includes the Early Childhood Longitudinal Study, Kindergarten Class of 1998-99 (ECLS-K) and the Early Childhood Longitudinal Study, Kindergarten Class of 2010-11 (ECLS-K:2011).

Data collections for the ECLS-B occurred when the children were approximately 9 months old (2001-2002), 2 years old (2003-2004), and 4 years old/preschool age (2005-2006). Additionally, in the 2006-07 school year, data were collected from all participating sample children, approximately 75 percent of whom were in kindergarten or higher. In the 2007-08 school year, data were collected from the approximately 25 percent of participating sample children who had not yet entered kindergarten or higher in the 2006-07 collection, as well as children who were repeating kindergarten in the 2007-2008 school year.

The longitudinal nature of the data allows for an examination of changes in children’s health status, including identifying health issues and special needs as children age.

System contact:
Gail Mulligan
Project Officer
National Center for Education Statistics
Phone: +1 (202) 245-8413

Information regarding prenatal care and delivery was obtained from the National Center for Health Statistics and is included in the data file.


Sample Design

Longitudinal survey.

Chinese children, other Asian and Pacific Islander children, American Indian and Alaska Native children, twins, and children born with low and very low birth weight were oversampled to allow for reliable estimates for these groups of children, which are relatively small in the general population.

To learn more:

Request sampling reports from the Institute of Education Sciences Data Security Office: (available to requestors with a restricted-use data license). Learn more.

Visit the following websites for publicly available information on the ECLS-B sample:
o 2006
o 2007

Sample Size

Approximately 14,000 children (born in 2001). The study’s final round of data collection occurred in the fall of the 2007-2008 school year.

Key Variables


NameMethods of Assessment
Disability (cognitive; equipment use; hearing; general; movement/physical; vision)Interview/questionnaire (parent/caregiver; teacher)
Father figure(s) in the house; existence of non-resident biological fatherInterview/questionnaire (parent/caregiver)
Household compositionInterview/questionnaire (parent/caregiver)
Household income and assetsInterview/questionnaire (parent/caregiver)
Month and year of birth (parent)Interview/questionnaire (parent/caregiver)
Race/ethnicity of the childBirth certificate and Interview/questionnaire (parent/caregiver)
Receipt of welfare or other public assistanceInterview/questionnaire (parent/caregiver)


NameMethods of Assessment
Breastfeeding/formula feedingInterview/questionnaire (parent/caregiver)
Eating routinesInterview/questionnaire (parent/caregiver)
Feeding practices (e.g., sleeps with a bottle)Interview/questionnaire (parent/caregiver)
Household food sufficiencyInterview/questionnaire (parent/caregiver)
Nutrition and dietInterview/questionnaire (parent/caregiver)
Participation in school breakfast or lunch programInterview/questionnaire (parent/caregiver)
Receipt of federal reimbursement for meals and snacksInterview/questionnaire (childcare provider)

Physical Activity-Related

NameMethods of Assessment
Frequency of physical activityInterview/questionnaire (teacher)
Neighborhood safetyInterview/questionnaire (parent/caregiver)
Before and after school care group versus individual activity participationInterview/questionnaire (parent/caregiver)
Participation in after-school activities (including indoor and outdoor play)Interview/questionnaire (parent/caregiver)


NameMethods of Assessment
Physical sleep environment: Items needed for sleep (e.g., stuffed animal, pacifier)Interview/Questionnaire with Parent
Schedule-related sleep environment: Adolescent work schedule/ school scheduleInterview/Questionnaire with Parent
Schedule-related sleep environment: Caregiver work scheduleInterview/Questionnaire with Parent
Sleep continuity: Number of awakeningsInterview/Questionnaire with Parent
Sleep disordered breathing: Sleep position (back, side, etc.)Interview/Questionnaire with Parent
Sleep disturbances and quality: Need of parent to initiate or resume sleepInterview/Questionnaire with Parent
Sleep disturbances and quality: Trouble falling back asleep at nightInterview/Questionnaire with Parent
Sleep timing and regularity: Sleep timing on workdays/schooldaysInterview/Questionnaire with Parent
Sleep timing and regularity: Time to bedInterview/Questionnaire with Parent
Sleep timing and regularity: Time woke upInterview/Questionnaire with Parent
Sleep-related behaviors: Bedwetting wetting, nocturia (nocturia may not apply to children)Questionnaire
Sleep-related policies: Daycare (napping/eating/recess schedules)Questionnaire
Sleep-related policies: Daycare (napping/eating/recess schedules)Interview/Questionnaire with Parent
Social sleep environment: Sleep location (e.g., living room)Interview/Questionnaire with Parent


NameMethods of Assessment
Child’s birth weightBirth certificate and Interview/questionnaire (parent/caregiver)
Height (length at 9 months), weight, and middle upper arm circumferenceMeasured
Mother’s weightInterview/questionnaire (parent/caregiver)
Mother’s weight before pregnancyInterview/questionnaire (parent/caregiver)
Mother’s weight gain during pregnancyInterview/questionnaire (parent/caregiver)
Parents’ weight loss due to food insufficiencyInterview/questionnaire (parent/caregiver)


NameMethods of Assessment
Zip code, county and state, NCES School IDN/A


NameMethods of Assessment
Child disabilty/iesInterview/questionnaire (parent/caregiver)
Child healthInterview/questionnaire (parent/caregiver)

Data Access and Cost

Data Availability

ECLS-B data in micro-data form (i.e., case-level data) are available only through a restricted-use data license agreement with the Institute of Education Sciences (IES). The restricted-use data DVD includes the raw data files, electronic codebook (ECB), user manuals, sampling reports, survey instruments, and data file record layouts. Learn more about the most recent data release, the ECLS-B Longitudinal 9-Month-Kindergarten 2007 Restricted-Use Data File and Electronic Codebook DVD. This longitudinal file contains all cases that ever participated in the study and includes important updates and corrections to errors discovered in previously released data.

A subset of variables from the ECLS-B 9-month data collection is available to the general public in the Data Analysis System (DAS), a software application that allows users to build tables of weighted estimates from the ECLS-B variables included in the DAS. An online tool allows calculation of t-tests from estimates produced in the DAS. Users also can produce correlation matrices for use in linear regression analysis.


Free of charge.

Special Note(s)

ECLS-B restricted-use data are provided to license holders on a password-protected DVD. Supplemental data sets (e.g., the Twin Triad dataset) also are available to restricted license holders. Learn more by visiting the Frequently Asked Questions section of the ECLS-B website.


Geocode Variable(s)

Zip codes as well as county and state information for the study child’s household and childcare center/provider are available on the ECLS-B Longitudinal 9-Month-Kindergarten 2007 Restricted-Use Data File. NCES school IDs are also available.

Existing Linkages

Additional information on children’s elementary schools is available by linking to school data from the National Center for Educational Statistics Common Core of Data (NCES/CCD) and Private School Universe Survey/Private School Survey Series (PSS) universe files, which pertain to U.S. public and private schools, respectively.

Special Note(s)

Although the ECLS-B data identifies the child’s state of residence, the sample was not designed to support state-level (or city- or county-level) estimates, as the sample is not representative of children in particular states (or cities or counties). As a result, conclusions cannot be made about children in any particular state using the ECLS-B data. Generalizations related to geographic location at the region level and by locale can be obtained using the data.

Selected Publications

For additional publications using ECLS-B data, visit ECLS Publications and Products and ECLS Bibliography.


Gibbs BG, Forste R. Socioeconomic status, infant feeding practices and early childhood obesity. Pediatr Obes. 2014 Apr;9(2):135-46.

Jacknowitz A, Novillo D, Tiehen L. Special supplemental nutrition program for women, infants, and children and infant feeding practices. Pediatrics 2007;119(2):281-289.

Kitsantas P, Pawloski LR. Maternal obesity, health status during pregnancy, and breastfeeding initiation and duration. Journal of Maternal-Fetal and Neonatal Medicine 2010;23(2):135-141.

Sparks PJ. Rural-urban differences in breastfeeding initiation in the United States. Journal of Human Lactation 2010;26(2):118-129.

Tandon PS, Zhou C, Christakis D. Frequency of Parent-Supervised Outdoor Play of U.S. Preschool-Aged Children. Archives of Pediatrics and Adolescent Medicine 2012; 166(8): 707-712.


Bronte-Tinkew J, Zaslow M, Capps R, Horowitz A, McNamara M. Food insecurity works through depression, parenting, and infant feeding to influence overweight and health in toddlers. Journal of Nutrition 2007;137(9):2160-2165.

Dawn R, Veneri D, Decker R, Gannotti M. Weight Status and Gross Motor Skill in Kindergarten Children. Pediatric Physical Therapy 2012; 24(4): 353-60.

Hinkle S, Sharma A, Swan D, Schieve L, Ramakrishnan U, Steing A. Excess Gestational Weight Gain is Associated With Child Adiposity Among Mothers with Normal and Overweight Prepregnancy Weight Status. Journal of Nutrition 2012; 142(10): 1851-1858.

Kitsantas P, Gaffney KF. Risk profiles for overweight/obesity among preschoolers. Early Human Development 2010;86(9):563-568.

Kitsantas P, Pawloski LR, Gaffney KF. Maternal prepregnancy body mass index in relation to Hispanic preschooler overweight/obesity. European Journal of Pediatrics 2010;169(11):1361-1368.

Li N, Strobino D, Ahmed S, Minkovitz CS. Is there a healthy foreign born effect for childhood obesity in the United States? Maternal and Child Health Journal 2010; March 14. Epub ahead of print.

Moss BG, Yeaton WH. U.S. Children's Preschool Weight Status Trajectories: Patterns From 9-Month, 2-Year, and 4-Year Early Childhood Longitudinal Study—Birth Cohort Data. American Journal of Health Promotion 2012; 26(3):172-175.

Oddo VM, Jones-Smith JC. Gains in income during early childhood are associated with decreases in BMI z scores among children in the United States. Am J Clin Nutr. 2015 Apr 15.


Flanagan KD, McPhee, C. The children born in 2001 at kindergarten entry: First findings from the kindergarten data collections of the Early Childhood Longitudinal Study, Birth Cohort (ECLS-B). Washington (DC): National Center for Education Statistics, Institute of Education Sciences, U.S. Department of Education, 2009. NCES 2010-005.

Jacobson Chernoff J, Flanagan KD, McPhee C, Park J. Preschool: First findings from the preschool follow-up of the Early Childhood Longitudinal Study, Birth Cohort (ECLS-B). Washington (DC): National Center for Education Statistics, Institute of Education Sciences, U.S. Department of Education, 2007. NCES 2008-025.

Najarian M, Snow K, Lennon J, Kinsey S. Early Childhood Longitudinal Study, Birth Cohort (ECLS-B), Preschool–Kindergarten 2007 psychometric report. Washington (DC): National Center for Education Statistics, Institute of Education Sciences, U.S. Department of Education, 2010. NCES 2010-009.


Data Query System


U.S. Department of Education, National Center for Education Statistics. Early Childhood Longitudinal Study, Birth Cohort (ECLS-B) 9-month—Kindergarten 2007 Restricted-Use Data File and Electronic Codebook (DVD). Washington (DC): U.S. Department of Education, 2009. NCES 2010-2011.


Before conducting any analyses, users are encouraged to review the ECLS-B study instrumentation to fully understand the study’s content, the flow of the items in the questionnaires/interviews, the group of respondents who answered specific questions, and the context in which the questions were asked.