Study Design & Methodology

The NLTS2 design, timeline, sampling plans, data collection, instrumentation, and analysis strategies were designed by SRI International, in collaboration with a task force representing interested audiences and an advisory panel.

The following design and methodology topics are covered on this page:

Sample

NLTS2 involves a large, nationally representative sample of students receiving special education who were ages 13 through 16 and in at least 7th grade on December 1, 2000. The oldest youth will be 26 at the time of final data collection. Statistical summaries generated from NLTS2 will generalize to students receiving special education nationally in this age group, to each of the 12 federal special education disability categories, and to each single-year age cohort. Click to view the NLTS2 Sampling Plan.

Conceptual Framework

Development of the conceptual framework that guides the study has been informed by a stakeholder group representing many of the audiences that will be interested in the results of the study, including parents, general and special educators, related service personnel, researchers, and policy-makers at the federal, state, and school district levels. In addition, the design team engaged a Technical Work Group of researchers experienced in large-scale longitudinal and survey research. Click here to view the NLTS2 Conceptual Framework and Research Questions.

Data Collection and Instruments

Information about youth will be collected repeatedly as they transition from secondary school to early adulthood. Given the broad range of topics that the conceptual framework encompasses, information for NLTS2 will be collected from a variety of sources, including parents/guardians, teachers, principals, school records, and students themselves. Click here to view the NLTS2 Study Design, Timeline, and Data Collection.

  • Parent/Guardian Interview Telephone interviews with parents/guardians focus on student and family characteristics, nonschool activities, satisfaction with school programs, and activities after high school. Click here to view the NLTS2 Parent Interview, Wave 1, NLTS2 Parent Interview Part 1, Wave 2, Part 2a, Wave 2, and Wave 3.
  • Youth Interview Youth able to answer for themselves are asked to complete a telephone interview or mail questionnaire about their experiences and outcomes. Click here to view the NLTS2 Youth Interview, Part 2b, Wave 2, Wave 3 .
  • Teacher Survey The teacher who provides instruction to a student during the first academic general education class on a typical Monday was surveyed about the classroom practices and the student's performance in that classroom. Click here to view the NLTS2 General Education Teacher Survey.
  • School Program Survey A teacher who knew the student's program well was surveyed about his/her overall program and performance more broadly (e.g., instructional settings that comprise the student's whole experience, vocational education and transition planning experiences, and acccommodations received). Click here to view the NLTS2 Student's School Program Survey, Regular School and the NLTS2 Student's School Program Survey, Special School.
  • School Characteristics Survey Information was collected once at the onset of the study on the characteristics of schools and data on aggregate measures of school performance to use as supporting data for reports. Click here to view the NLTS2 School Characteristics Survey, Regular School and the NLTS2 School Characteristics Survey, Special School.
  • Student Assessment A direct assessment of students was conducted, including measures of students' reading and math skills, vocabulary, science and social studies content knowledge, as well as interviews about self-concept and self-determination. An Alternate Assessment (checklist completed by knowledgeable adult) was used when a student was unable to complete a direct assessment due to cognitive or behavioral limitations. Click here to view the NLTS2 Direct Assessment Content and Process.
  • Transcripts Transcripts are collected to learn about course-taking patterns, grades, and attendance.

Analyses of Potential Bias

Response rates may affect statistical precision or sample bias. NLTS2 investigated potential bias in the sample of LEAs from which study participants were randomly selected and in the sample of Wave 1 and Wave 2 respondents. Using analyses of extant databases and a survey of a national sample of Directors of Special Education, NLTS2 reports on the Analysis of Potential Bias in the Sample of Local Education Agencies (LEAs) in the National Longitudinal Transition Study-2 (NLTS2) Sample. The implications of response rates to various NLTS2 instruments are reported in Analysis of Potential Bias in the Wave 1 and Wave 2 Respondents to the National Longitudinal Transition Study-2 (NLTS2).

Links to SEELS

The NLTS2 conceptual framework and research questions are designed to allow analyses of the relationships between NLTS2 data and data generated by OSEP's Special Education Elementary Longitudinal Study (SEELS). This 6-year study, following a group of students in special education (6 to 12 years old as of September 1, 1999), assessed the experiences and achievements of students as they transitioned from elementary to middle and middle to high school. The overlap of NLTS2 and SEELS students in high school will permit linkage of the early school factors measured in SEELS with postschool experiences measured in NLTS2.

Original NLTS

The design of NLTS2 also reflects a careful alignment with the first National Longitudinal Transition Study (NLTS), conducted by SRI International for OSEP from 1985 through 1993. By including many of the same research questions and data items that appeared in NLTS, the new study will provide important information about the ways in which secondary education and postschool experiences have changed for youth with disabilities in the previous decade or more.

National Comparisons

The data collection instruments have been designed to include items that have been collected in national databases for the general youth population. This will permit appropriate comparisons between NLTS2 youth and those of the same ages in the general population of youth.