Data source

The Survey of Earned Doctorates (SED) is the sole data source for Doctorate Recipients from U.S. Universities: 2021. The principal elements of the 2021 SED data collection are described in the sections that follow. More detailed information, including “Technical Notes” and related technical tables, are available at

Survey eligibility. The SED collects information on research doctorate recipients only. Research doctorates require the completion of a dissertation or equivalent project, are oriented toward preparing students to make original intellectual contributions in a field of study, and are not primarily intended for the practice of a profession. The 2021 SED recognized 18 distinct types of research doctorates. In 2021, 98% of research doctorate recipients earned the PhD.

The population eligible for the 2021 survey consisted of all individuals who received a research doctorate from an accredited U.S. academic institution in the 12-month period from 1 July 2020 to 30 June 2021.

Survey universe. The total universe consisted of 52,250 persons in 456 institutions that conferred research doctorates in academic year 2021.

Data collection. Institutional coordinators at each doctorate-awarding institution distributed the SED Web survey link to individuals receiving a research doctorate. The self-administered Web survey is the primary mode of SED completion. Nonrespondents were contacted by e-mail and mail to complete the Web survey. If the series of follow-up e-mails and mailings is unsuccessful, the survey contractor attempts to reach nonrespondents to complete an abbreviated survey by computer-assisted telephone interviewing. RTI International served as the 2021 SED data collection contractor on behalf of NCSES.

Survey response rates. In 2021, 91.5% of research doctorate recipients completed the survey. Limited records (field of study, doctoral institution, and sex) are constructed for nonrespondents from administrative records of the university—commencement programs, graduation lists, and other public records—and are included in the reported total of doctorate recipients. The survey response rates for 1980–2021 and the item response rates for 2010–20 are provided in table A-2 and table A-3 of the survey’s 2021 “Technical Notes.”

Time series data changes.

  • EdD program reclassification. After a multiyear review of Doctor of Education (EdD) degree programs participating in the SED, 143 programs were reclassified from research doctorate to professional doctorate over the 2010–11 period. No additional reclassifications of EdD degree programs are planned. SED data are no longer being collected from graduates earning degrees from the reclassified EdD programs, and this has affected the reporting of the number of doctorates awarded by sex, citizenship, race, and ethnicity. Figure 8 in this report shows the impact of the decline in number of doctoral degrees awarded in education from 2009 to 2011. Readers should note that the declines from 2009 to 2010 and from 2010 to 2011 are at least partly attributable to the EdD reclassification.
  • Field. Beginning in 2021, field of doctorate data are collected using a modified version of the 2020 Classification of Instructional Programs (CIP) codes and reported using a new SED-specific taxonomy (table A-4). For more information about CIP codes, please see Adjustments to the 2020 CIP for the SED data collection (SED-CIP) included, among other changes, the addition of over 50 fields of study codes collected in the SED but not covered in the 2020 CIP. The SED-CIP now collects over 1,600 fields for field of study reporting, compared to the 334 field codes collected in 2020 SED and prior years. The SED-CIP codes collected are then aggregated into 300 detailed fields nested under 66 major fields and 16 broad fields, which are used for reporting in the 2021 detailed data tables. This field structure is aligned with the NCSES Taxonomy of Disciplines (TOD) to facilitate comparison with other NCSES surveys as well as with the Integrated Postsecondary Education Data System (IPEDS) Completions survey. To facilitate the trend data comparison with prior years, a crosswalk was created of the SED-CIP codes to the SED historical field of study, as shown in table A-6 of the 2021 “Technical Notes.” Thus, the broad fields are estimates generated to facilitate the comparison of trend data collected using SED-CIP codes to those collected using the historical SED field. This results in generally comparable broad fields. For more details, see the 2021 “Technical Notes.”

Data license. Microdata from the Doctorate Records File (cumulative SED data file) may be obtained through a restricted-use data license. (See