PEDAR: Research Methodology  Waiting to Attend College: Students Who Delay Their Postsecondary Enrollment
The 1999-2000 National Postsecondary Student Aid Study
The National Education Longitudinal Study of 1988
Beginning Postsecondary Students Longitudinal Study
Accuracy of Estimates
Item Response Rates
Data Analysis System
Statistical Procedures
Differences Between Means
Linear Trends
Multivariate Commonality Analysis
Missing Data dn Adjusting for Complex Sampling Design
Interpreting the Results
Executive Summary
Full Report (PDF)
Executive Summary (PDF)

The 1999–2000 National Postsecondary Student Aid Study (NPSAS:2000) is the latest in a series of comprehensive studies of all students enrolled in postsecondary education in the United States and Puerto Rico. The study is conducted by the U.S. Department of Education’s National Center for Education Statistics (NCES) to determine how students and their families pay for postsecondary education.1 It also describes demographic and other characteristics of students enrolled. The first NPSAS study was conducted in 1986–87 (NPSAS:87) and since then four additional studies have been conducted (NPSAS:90, NPSAS:93, NPSAS:96, and NPSAS:2000). The sixth administration (NPSAS:2004) is currently being conducted.

The institutional sampling frame for NPSAS:2000 was constructed from the 1998–99 Integrated Postsecondary Education Data System (IPEDS) Institutional Characteristics (IC) file and, because NPSAS:2000 also served as the base-year survey for a longitudinal study of baccalaureate recipients, the 1996–97 IPEDS Completions file. Eligible institutions were partitioned into 22 institutional strata based on institutional control, highest level of offering, and percentage of baccalaureate degrees awarded in education. Approximately 1,100 institutions were initially selected for NPSAS:2000, and all but 10 of these institutions were found to be eligible. Sampling frames for selecting students consisted of enrollment lists or data files provided by the institutions for those students enrolled during the NPSAS:2000 year, and at least 40 students were sampled from each institution. The study is based on a nationally representative sample of all students in postsecondary education institutions, including undergraduate, graduate, and first-professional students. Information was obtained from approximately 50,000 undergraduate, 10,600 graduate, and 1,200 first-professional students. They represented about 16.5 million undergraduates, 2.4 million graduate students, and 300,000 first-professional students who were enrolled at some time between July 1, 1999, and June 30, 2000.

Data were collected using computer-assisted telephone and in-person interviews (CATI and CAPI). Supplementary sources of data included the National Student Loan Data System (NSLDS), ACT database, SAT records from ETS, Central Processing System data, and data from institutions collected using a computer-assisted data entry (CADE) program. Data editing and imputations were conducted both during the interview and after data collection was complete. Range editing, item consistency, and other checks were made to ensure data quality, and logical imputation was performed where appropriate.

The institutional response rate was 91 percent, CATI response rate was 72 percent, and the weighted overall student interview response rate was 65.6 percent.2 Because the student telephone interview response rate for NPSAS:2000 was less than 70 percent in some institutional sectors, an analysis was conducted to determine if computer assisted telephone interview (CATI) estimates were significantly biased due to CATI nonresponse. Considerable information was known for CATI nonrespondents, and these data were used to analyze and reduce the bias. The distributions of several variables using the design-based, adjusted weights for study respondents (study weights) were found to be biased before CATI nonresponse adjustments. The CATI nonresponse and poststratification procedures, however, reduced the bias for these variables, and the remaining relative bias ranged from 0 to 0.35 percent.3 The weight used in this analysis is WTB00, the weight applied to all CATI respondents.

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