S&E Degrees: 1966–2008
Appendix A. Technical Notes
Bachelor's and Master's Degree Data
Data from the Integrated Postsecondary Education Data System (IPEDS) Completions Survey were used to report numbers of bachelor's and master's degrees. The Completions Survey, conducted by the National Center for Education Statistics (NCES), U.S. Department of Education, collects data annually on all degrees conferred between 1 July of one year and 30 June of the following year from the universe of accredited institutions of higher education in the 50 states, the District of Columbia, and the U.S. territories and outlying areas. Institutional representatives submit data to the IPEDS online collection system. The survey is mandatory for all institutions that participate in or are applicants for participation in any federal financial assistance program authorized by Title IV of the Higher Education Act of 1965, as amended. Data are collected according to sex of recipient and field of study. For more information on IPEDS, see http://nces.ed.gov/IPEDS/about/.
Each year between 1966 and 2008, institutional response rates to the survey have exceeded 99%. Imputations for nonresponse were based on the previous year's response for an institution. For bachelor's and master's degree data, the percentage of degrees imputed rounds to zero.
Because the data in this report include those for institutions in the U.S. territories, they may differ from numbers published by NCES that relate to the 50 states and the District of Columbia and their field groupings. Data on degrees by field of study were collected according to the NCES Classification of Instructional Programs (CIP) (see appendix B). Information on the CIP is available at http://nces.ed.gov/pubs2002/cip2000/.
Through 1995, IPEDS reports were concerned primarily with the subset of postsecondary institutions that were accredited at the college level by an agency recognized by the Secretary, U.S. Department of Education. The S&E Degrees report presented counts of bachelor's and master's degrees from this same subset of institutions. Beginning with 1996 data, NCES categorized the postsecondary institutional universe on the basis of degree-granting status as well as eligibility for Title IV federal financial aid (based on a list of eligible institutions maintained by the Department of Education's Office of Postsecondary Education). This change expanded the types of institutions whose data appear in NCES reports to include for-profit and online institutions. NCSES chose to retain the earlier, less inclusive institutional coverage criterion for the data in the S&E Degrees report. As a result, beginning with the 1996 edition, the counts of bachelor's and master's degrees presented in S&E Degrees reports diverged from the degree counts reported by IPEDS. With this edition, the S&E Degrees report has adopted the more inclusive institutional coverage of the IPEDS reports, and the bachelor's and master's degree counts from 2000 forward are now based on the larger set of institutions. Owing to field classification issues, the change in institutional coverage was not extended all the way back to the original divergence in 1996; thus, data for 2000 and later are not comparable to data for earlier years, and the bachelor's and master's degree counts for 2000 to 2006 appearing in this edition of the S&E Degrees report differ from the degree counts reported in earlier editions for those years. Also, detailed national data were not released by NCES for the academic year ending 1999, and so bachelor's and master's degree data for those years are missing from all tables.
Doctoral Degree Data
Data on doctoral degrees were derived from the Survey of Earned Doctorates (SED), funded jointly by the National Science Foundation (NSF), the National Institutes of Health, the U.S. Department of Education, the U.S. Department of Agriculture, the National Aeronautics and Space Administration, and the National Endowment for the Humanities.
The SED is a voluntary survey that collects information annually for the period of 1 July of one year through 30 June of the following year from all persons who have fulfilled the requirements for a research doctorate at an accredited U.S. institution. SED data were preferred over Completions Survey data for doctoral degrees because the self-reported data provided by individual doctorate recipients are more specific with respect to the field of specialization. Furthermore, self-reported data provide almost complete coverage for data by field and sex of individual recipients, whereas institutional data are subject to imputation for nonresponse.
The survey forms are sent to all accredited U.S. doctorate-granting institutions for distribution by the graduate deans to all research doctorate recipients as they complete degree requirements. The survey collects demographic data, such as the student's sex, citizenship, and racial/ethnic group; educational history, including field of degree; sources of graduate student support; employment status during the year preceding receipt of the doctorate; postgraduation plans; and background on parents' education.
Approximately 92% of doctorate recipients complete and return the survey forms. For nonrespondents, commencement programs, graduation lists, and other similar public records allow construction of partial records, limited to field of study, year of doctorate, doctoral institution, and sex, which are added to the data file. Consequently, for the variables used in this report, there is almost complete coverage. Data are updated annually from completed survey forms submitted belatedly by previous nonrespondents; therefore, data on doctorates are subject to revision and may differ slightly from reports published earlier. For more information on the SED, see http://www.nsf.gov/statistics/doctorates/.
Field Classification Schemes
Four field classification systems were used during the 1966–2008 period covered by this report. The current classification scheme for the CIP is used for the Completions Survey; it and corresponding fields for the SED are provided in appendix B, "Classification of Programs." Data for earlier years are presented as consistently as possible with the current classification schemes.
Note that the data in this report are grouped into the science and engineering categories used by NSF. Data on engineering technology degrees and degrees in health/medical fields are not included in the science and engineering totals here. Therefore, data in this report may differ from those in reports published by the U.S. Department of Education. However, separate tables for engineering technology and for health medical fields, as well as for first professional degrees, are included in this report.
Beginning with this edition of the S&E Degrees report, the constituent fields of study reported in two social sciences fields and six engineering fields were changed. Consequently, the counts of degrees in the eight affected data tables differ from the counts reported in pre-2007 editions of this report, as explained in the following paragraphs.
To summarize the changes in the eight affected data tables: (1) counts of doctoral degrees reported in 2007–08 and later editions of the S&E Degrees report differ from the counts reported in pre-2007 editions, and the differences occur in all years reported in the eight data tables; (2) counts of bachelor's and master's degrees reported in 2007–08 and later editions of the S&E Degrees report differ from the counts reported in pre-2007 editions, but the differences occur only in the data for 2000 and later years.
 A research doctorate is a doctoral degree that (1) requires the completion of an original intellectual contribution in the form of a dissertation or an equivalent project of work (e.g., musical composition) and (2) is not primarily intended for the practice of a profession. Doctoral degrees, such as the PhD, DSc, and research EdD, are included in this survey; professional doctoral degrees, such as the MD, JD, DDS, PsyD, and DMin, are not.