DOI: 10.3886/icpsr03676.v1
title: Early Childhood Longitudinal Study [United States]: Kindergarten Class of 1998-1999
title: Version 1

description: The Early Childhood Longitudinal Study (ECLS) program
provides national data on children's status at birth and at various
points thereafter, children's transition to nonparental care, early
education programs, and school, and children's experiences and growth
through the fifth grade. ECLS also provides data to test hypotheses
about the effects of a wide range of family, school, community, and
individual variables on children's development, early learning, and
early performance in school. The Kindergarten Class of 1998-1999
addresses four key issues: (1) school readiness, (2) children's
transitions to kindergarten, first grade, and beyond, (3) the
relationship between children's kindergarten experience and their
elementary school performance, and (4) children's growth in math,
reading, and general knowledge (i.e., science and social studies), and
their progress through elementary school.
description: There are several sets of K-1 longitudinal weights computed for children with complete data from different combinations of rounds. All K-1 longitudinal weights are child-level weights. There are no K-1 longitudinal weights at the school or teacher level since school- and teacher-level weights are not computed for the first grade year due to lack of representativeness.
Weight to be used for analysis of ...

<strong>C23CW0 - </strong>child direct assessment data from BOTH spring-kindergarten and fall-first grade, alone or in conjunction with any combination of a limited set of child characteristics (e.g., age, sex, race-ethnicity).
<strong>C23PW0 - </strong>parent interview data from BOTH spring-kindergarten and fall-first grade.
<strong>C123CW0 - </strong>child direct assessment data from fall- AND spring-kindergarten AND fall-first grade, alone or in conjunction with any combination of a limited set of child characteristics (e.g., age, sex, race-ethnicity).
<strong>C123PW0 - </strong>parent interview data from fall- AND spring-kindergarten AND fall-first grade.
<strong>C24CW0 - </strong>child direct assessment data from BOTH spring-kindergarten and spring-first grade, alone or in conjunction with any combination of a limited set of child characteristics (e.g., age, sex, race-ethnicity).
<strong>C24PW0 - </strong>parent interview data from BOTH spring-kindergarten and spring-first grade.
<strong>C124CW0 - </strong>child direct assessment data from fall-kindergarten AND spring-kindergarten AND spring-first grade, alone or in conjunction with any combination of a limited set of child characteristics (e.g., age, sex, race-ethnicity).
<strong>C124PW0 - </strong>parent interview data from fall-kindergarten AND spring-kindergarten AND spring-first grade.
<strong>C1_4CW0 - </strong>child direct assessment data from all four rounds of data collection, alone or in conjunction with any combination of a limited set of child characteristics (e.g., age, sex, and race-ethnicity).
<strong>C1_4PW0 - </strong>parent interview data from all four rounds of data collection.
<strong>Y2COMW0 - </strong>child direct assessment data from fall-kindergarten AND spring-kindergarten AND spring-first grade, in conjunction with parent and/or teacher data from spring-first grade, AND one or more base year rounds of parent and/or teacher data.

<strong>Choosing a Weight</strong>
Each SDA file is set up to use a different weight. To choose the appropriate file/weight for your analysis, first decide which two or more points in time are the focus of your analysis. The analysis could pertain to two points in time (e.g., spring-kindergarten and fall-first grade, or spring kindergarten and spring-first grade), three points in time (any three of fall-kindergarten, spring-kindergarten, fall-first grade, and spring-first grade), or four points in time (all four rounds of data). For example, if the analysis uses spring-kindergarten and fall-first grade data, then the appropriate weight would be one that begins with C23 (denoting child-level data from round 2 AND round 3). Second, consider the source of the data, which also affects the choice of the weight, based on whether the data were collected through the child assessments, parent interviews, or teacher questionnaires A or B.
<strong>Examples:</strong>
K-1 longitudinal weights are used to produce estimates of differences between two or more rounds of data collection spanning across both kindergarten and first grade.

<strong>Less complex decision examples involving two rounds of data collection are as follows:</strong> (1) Estimates of the differences in children's mean assessment scores between spring kindergarten and spring first grade would use C24CW0 (2) estimates of the difference in social rating scores as reported by parents during the same time period would use C24PW0.
<strong>A more complex decision example involving more than two rounds of data follows:</strong> Examining whether gains children make in their reading knowledge and skills during the kindergarten year and from the end of kindergarten to the end of first grade are related to parents' and teachers' beliefs about kindergarten readiness and parental educational expectations. In this case, the weight Y2COMW0 would be appropriate.
description: A nationally representative sample of approximately 22,000
children who enrolled in about 1,000 kindergarten programs (both
private and public) during the 1998-1999 school year, and their
families, teachers, and schools.
description: Datasets: 
DS0: Study-Level Files
DS1: Child Data
DS2: Child Data: C23CW0 - child direct assessment data from both spring-kindergarten and fall-first grade (Online Analysis Only)
DS3: Child Data: C23PW0 - parent interview data from both spring-kindergarten and fall-first grade (Online Analysis Only)
DS4: Child Data: C123CW0 - child direct assessment data from fall- and spring-kindergarten and fall-first grade (Online Analysis Only)
DS5: Child Data: C123PW0 - parent interview data from fall- and spring-kindergarten and fall-first grade (Online Analysis Only)
DS6: Child Data: C24CW0 - child direct assessment data from both spring-kindergarten and spring-first grade (Online Analysis Only)
DS7: Child Data: C24PW0 - parent interview data from both spring-kindergarten and spring-first grade (Online Analysis Only)
DS8: Child Data: C124CW0 - child direct assessment data from fall-kindergarten and spring-kindergarten and spring-first grade (Online Analysis Only)
DS9: Child Data: C124PW0 - parent interview data from fall-kindergarten and spring-kindergarten and spring-first grade (Online Analysis Only)
DS10: Child Data: C1_4CW0 - child direct assessment data from all four rounds of data collection (Online Analysis Only)
DS11: Child Data: C1_4PW0 - parent interview data from all four rounds of data collection (Online Analysis Only)
DS12: Child Data: Y2COMW0 - child direct assessment data from fall-kindergarten and spring-kindergarten and spring-first grade (Online Analysis Only)
description: Children, and their families, teachers, and schools in the
United States.
description: Users are advised to review the errata file prior
to conducting any analyses.Users should note the organization of
the information in this collection. The data file contains data for
both the Base Year and the First Grade as units of analysis. The same
data file, user guide, and SAS and SPSS setup files are used for both
units of analysis and appear in Dataset 0001, Base Year and First
Grade Data. The files to be used with either unit of analysis, are
further identified with the term, all, in their filenames. Each unit
of analysis has its own documentation and questionnaire with those for
the Base Year found in Dataset 0001 and those for the First Grade
found in Dataset 0002, First Grade Codebook and Instruments.