Pioneering progress with data: how over 30 years of research influenced the education system for students with disabilities

Girl in wheelchair in school library

Developing effective policies and best practices to improve education for students with disabilities.

In the 1980s, little was known about the characteristics, services and outcomes of children with disabilities. This is in part because gathering data to track outcomes nationally over long periods of time is difficult. As such, the U.S. Department of Education needed help creating national longitudinal studies to measure services, identify gaps and monitor trends for students with disabilities from childhood to early adulthood.

SRI Education pioneered six national longitudinal studies over the course of three decades that unlocked fundamental insights for special education policy and research communities. SRI’s unique research has been instrumental in developing many of today’s early intervention, special education services and federal special education legislation policies. Combined, these programs impact 15.6 million children and youth.

SRI has been active in special education and disability work since the Education for All Handicapped Children Act, now the Individuals with Disabilities Education Act (IDEA), was passed in 1975. After the success of its pioneering National Longitudinal Transition Study (NLTS) starting in 1984, SRI developed a portfolio of longitudinal studies to provide national information about the full range of students receiving services under IDEA that is still underway today.

The National Longitudinal Transition Study 2 (NLTS2), provided a nationally representative sample that allows for the examination of services and outcomes experienced by youth with specific disabilities. In 2011, SRI completed NLTS2, which involved a nationally representative sample of more than 11,000 13- to 16-year-olds receiving special education in grades seven and above.

Boy with Downs syndrome going to elementary school

Data from the series of studies has been used by researchers to disseminate more than 2,000 publications and presentations that promote understanding of the characteristics, experiences and outcomes of children and youth with disabilities.

Stemming from SRI’s contribution to enlightening policymakers and practitioners about the status of students with disabilities from early childhood to early adulthood, significantly more children and youth with disabilities were included with their peers in the general population in regular education classrooms (35% in 1990 vs. 62% in 2015). Furthermore, more students with disabilities completed high school (54% in 1987 vs. 65% in 2015).

Currently, SRI is teaming with RTI on NLTS 2012 Phase II, which is collecting and analyzing outcome data focused on high school course taking and postsecondary education, employment outcomes and experiences of a sample of more than 20,000 individuals with disabilities, as well as a small comparison sample of individuals in the general population.

The data builds off past findings and offers valuable insight into characteristics of youth receiving special education services in high school and their households; their secondary school experiences, including schools, school programs; their transition experiences; and their achievements in and after high school in the education, employment, social and residential domains.

Below is the list of longitudinal studies conducted by SRI, and some of the recent journal publications produced using the nationally representative datasets from the NLTS2 and other longitudinal studies.

Longitudinal studies:

  • National Early Intervention Longitudinal Study of Infants and Toddlers (NEILS, 1996-2007)
  • Designed Preschool Education Longitudinal Study
  • Special Education Elementary Longitudinal Study (SEELS, 2000-2007)
  • National Longitudinal Transition Study (NLTS, design contract, 1984-87; study contract, 1987-1993), ages 13 through 21
  • National Longitudinal Transition Study-2 (NLTS2, 2000-2011), ages 13 through 16
  • National Longitudinal Transition Study 2012 Phase II, a subcontract with RTI (NLTS 2012, 2015-2022), ages 13 to 21

Recent journals and publications:

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