NotesFAQContact Us
Search Tips
Back to results
Peer reviewed Peer reviewed
Direct linkDirect link
ERIC Number: EJ1213931
Record Type: Journal
Publication Date: 2019-Jun
Pages: 19
Abstractor: As Provided
ISSN: ISSN-0162-3737
What Is in a Definition? The How and When of Special Education Subgroup Analysis in Preschool Evaluations
Shapiro, Anna; Weiland, Christina
Educational Evaluation and Policy Analysis, v41 n2 p145-163 Jun 2019
There are unique challenges to estimating causal effects of preschool for students with special needs that have not received attention in the literature. We revisit the Head Start Impact Study (HSIS) to illustrate that when and how special needs is defined has implications for the internal validity of and interpretation of special needs subgroup impact estimates. We find that the treatment group in the HSIS was three percentage points more likely to be classified as special education (SD = 0.11, p < 0.001) at baseline, likely biasing the impact estimates for this subgroup. We also find that the estimated intent-to-treat effects of Head Start on cognitive and socioemotional measures are sensitive to subgroup definition.
SAGE Publications. 2455 Teller Road, Thousand Oaks, CA 91320. Tel: 800-818-7243; Tel: 805-499-9774; Fax: 800-583-2665; e-mail:; Web site:
Publication Type: Journal Articles; Reports - Research
Education Level: Early Childhood Education; Preschool Education
Audience: N/A
Language: English
Sponsor: Institute of Education Sciences (ED)
Authoring Institution: N/A
Identifiers - Assessments and Surveys: Peabody Picture Vocabulary Test; Child Behavior Checklist; Woodcock Johnson Tests of Achievement
IES Funded: Yes
Grant or Contract Numbers: R305B150012