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Statistical Standards
Statistical Standards Program
Table of Contents
1. Development of Concepts and Methods
2. Planning and Design of Surveys

2-1 Design of Surveys
2-2 Survey Response Rate Parameters
2-3 Developing RFPs for Surveys
2-4 Pretesting Survey Systems
2-5 Maintaining Data Series Over Time
2-6 Educational Testing

3. Collection of Data
4. Processing and Editing of Data
5. Analysis of Data / Production of Estimates or Projections
6. Establishment of Review Procedures
7. Dissemination of Data
Appendix A
Appendix B
Appendix C
Appendix D
Publication information

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PURPOSE: To maintain and report NCES data series that are consistent over time.

KEY TERMS: bridge study, consistent data series, crosswalk study, and key variables.

STANDARD 2-5-1: NCES must maintain and report on a consistent set of data series that may be analyzed over time. Ongoing data collections must maintain and report on a consistent set of key variables, which are based on consistent data collection procedures.

    GUIDELINE 2-5-1A: Identify the basic key variables to be assessed on a regular basis to address policy issues and other information needs.

    GUIDELINE 2-5-1B: Provide estimates of both change and level for time series data in reports. For survey reports, consider publishing 3 or more years of the time series data along with the current year to highlight the time series.

    GUIDELINE 2-5-1C: Provide a list of other publications containing the data for previous years in the appendix of a survey report.

STANDARD 2-5-2: Continuous improvement efforts sometimes result in a trade-off between the desire for consistency and a need to improve a data collection. If changes are needed in key variables or survey procedures for data series, a plan must be developed that provides the justification or rationale for the changes in terms of their usefulness for policy-makers, conducting analyses, and addressing information needs. The plan must also describe adjustment methods, such as crosswalks and bridge studies that will be used to preserve trend analyses.

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National Center for Education Statistics -
U.S. Department of Education