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. NLTS2 design elements include:

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.

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 who are experienced in large-scale longitudinal and survey research.

Data collection 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.

• 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.
  
  
• Youth Interview - Youth able to answer for themselves will be asked to complete a telephone interview or mail questionnaire about their experiences and outcomes.
  
  
• Teacher Survey - The teacher who provides instruction to a student during the first academic class on a typical Monday will be surveyed about the classroom practices and the student's performance in that classroom.
  
  
• School Program Survey - A teacher who knows the student's program well will be 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).
  
  
• School Characteristics Survey - We will collect information on the characteristics of schools and data on aggregate measures of school performance.
  
  
• Student Assessment - A direct assessment will be 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.
  
  
• Transcripts - Transcripts will be collected to learn about coursetaking patterns, grades, and attendance.

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), is assessing the experiences and achievements of students as they transition from elementary to middle and middle to high school. The overlap of NLTS2 and SEELS students in high school will permit statistically linking 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 results and postschool experiences have changed for youth with disabilities in the previous decade or more.

National comparisons. Data collection instruments have been designed to include items in national databases for the general youth population in order to permit appropriate comparisons between NLTS2 youth and those of the same ages in the general population of youth.