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Science and Engineering Doctorates

Survey of Earned Doctorates

Survey Overview (2015 survey cycle)

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The Survey of Earned Doctorates (SED) collects data on the number and characteristics of individuals receiving research doctoral degrees from U.S. academic institutions.
Data collection authority
The information collected by the SED is solicited under the authority of the National Science Foundation Act of 1950, as amended. The Office of Management and Budget control number is 3145-0019, expiration date 30 June 2016.
Major changes to recent survey cycle

Key Survey Information

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Initial survey year
Academic year 1957–58.
Reference period
Most recent year of available data, the academic year 1 July 2014 to 30 June 2015.
Response unit
Sample or census
Population size
Approximately 55,000.
Sample size
Not applicable.
Key variables
Key variables of interest are listed below.
  • Academic institution of doctorate
  • Baccalaureate-origin institution (U.S. and foreign)
  • Birth year
  • Citizenship status at graduation
  • Country of birth and citizenship
  • Disability status
  • Educational attainment of parents
  • Educational history in college
  • Field of each degree earned (N=326 fields)
  • Graduate and undergraduate educational debt
  • Marital status, as well as the number and age of dependents
  • Postgraduation plans (work, postdoc, other study or training)
    • Primary and secondary work activities
    • Source and type of financial support for postdoctoral study or research
    • Type and location of employer
    • Basic annual salary
    • Race and ethnicity
    • Sex
    • Sources of financial support during graduate school
    • Type of academic institution (e.g., historically black colleges and universities, Carnegie codes, control) awarding the doctorate

Survey Design

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Target population

The population for the 2015 SED consists of all individuals receiving a research doctorate from a U.S. academic institution in the 12-month period beginning 1 July 2014 and ending 30 June 2015. A research doctorate is a doctoral degree that (1) requires completion of an original intellectual contribution in the form of a dissertation or an equivalent culminating project (e.g., musical composition) and (2) is not primarily intended as a degree for the practice of a profession. The most common research doctorate degree is the PhD. Recipients of professional doctoral degrees, such as MD, DDS, DVM, JD, DPharm, DMin, and PsyD, are not included in the SED.

Sample frame

The total universe in 2015 included 55,006 persons from 432 institutions that conferred research doctorates.

Sample design

The SED is a census of all individuals receiving a research doctorate from a research doctorate-granting U.S. academic institution in the academic year 1 July through 30 June of the next year.

Data Collection and Processing

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Data collection

Three modes of data collection are used in the SED: self-administered paper surveys, Web-based surveys, and computer-assisted telephone interviews (CATI). Paper surveys are mailed to institutional coordinators in the graduate schools who then distribute the surveys to students receiving research doctorates. The institutional coordinators collect the completed surveys and return them to the survey contractor for editing and processing.

Since 2001, a Web-based SED option has been available. When students apply for graduation, institutional coordinators at some universities give them paper surveys and the link to the survey registration website; institutional coordinators at other universities give only the link to the survey registration website. Students who sign up at the survey registration website receive PIN and password information via e-mail, as well as the URL of the Web-based SED. The proportion of completed surveys from respondents using the Web-based SED has increased each year since 2001, and it reached 93% in 2015.

Both paper and Web-based survey instruments are used in follow-up mailings and e-mailings to nonrespondents. If these follow-up attempts are unsuccessful, the survey contractor since 2005 has attempted to reach nonrespondents by phone to administer a computer-assisted telephone interview (CATI) abbreviated questionnaire. Approximately 1%–2% of respondents use the CATI-based SED each year. A paper survey is also mailed to individual respondents and institutions when critical SED questionnaire items are missing.

Data processing

The data collected in the SED are subject to automated editing procedures. No imputation is performed for missing data items.

Estimation techniques

The survey is a census, which does not require any sampling; weighting is not used to adjust for nonresponse.

Survey Quality Measures

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Sampling error

Not applicable because the SED is a census.

Coverage error

Due to the availability of comprehensive lists of doctorate-granting institutions and the institutions’ high levels of participation in the survey, coverage error of institutions is minimal. Because the graduate schools collect the questionnaires from degree recipients at the time of doctorate completion, coverage error for the universe of doctorate recipients is also minimal. Comparisons of the institutions and the number of research doctorate recipients covered by the SED with the total number of doctorate recipients (including nonresearch doctorate degree recipients) reported by institutions to the National Center for Education Statistics confirm that there is minimal coverage error of doctorate recipients. Institutions that begin to confer research doctorates are asked to join the SED. If a university that confers research doctorates does not wish to participate in the SED, slight undercounts may result.

Nonresponse error
Unit nonresponse.

Of the 55,006 individuals granted a research doctorate in 2015, 90.2% completed the SED. Records for nonrespondents are constructed from limited information (doctoral institution, year of doctorate, field of doctorate, type of doctorate, and, if available, baccalaureate institution, master’s degree institution, and sex) collected from commencement programs, graduation lists, and other similar public records. Student nonresponse is concentrated in certain institutions. The 43 institutions with the highest percentage of students not responding accounted for 65% of the total number of nonrespondents.

Item nonresponse.

Item nonresponse rates in 2015 for the five key SED demographic variables—sex, citizenship, country of citizenship, race and ethnicity, and location after graduation—range from 0.02% for sex to 10.1% for location after graduation.

Measurement error

Measurement error in the SED is attributable to several sources, including error in recording respondent data (calculated at less than 1%), and editing error (calculated at 0.66%) for some variables due to the difficulty of defining some concepts. For example, an SED respondent may classify his or her doctoral field of specialization differently than the department or university does in its institutional reporting for the NCES Completions Survey.

Data Comparability

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Data availability

Each year's survey data are compiled into the Doctorate Records File (DRF) and trend data are available back to 1957–58; more limited information (sex, institution, field, and year of doctorate) is contained on the DRF for PhDs who graduated from 1920–56.

Data comparability

Because of procedural changes implemented during the 1990 survey cycle to improve the completeness of race, ethnicity, and citizenship data, the data from 1990 and later years are not directly comparable to data before 1990.

Data Products

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The data from this survey are published annually in a publication series reporting on all fields of study, the latest edition of which is Doctorate Recipients from U.S. Universities: 2015.

Additional data from this survey for earlier years are published in Science and Engineering Doctorates: 1960–91 (NSF 93-301). Also available is the interagency report U.S. Doctorates in the 20th Century, which provides an overview of the development of a national resource—the American system of doctoral education—from 1900 to 1999.

Information from the survey is also included in the series Science and Engineering Degrees, in Science and Engineering Degrees, by Race/Ethnicity of Recipients, in Science and Engineering Indicators, and in Women, Minorities, and Persons with Disabilities in Science and Engineering.

Electronic access

Access to tabular data on selected variables from 1966 onward is available through WebCASPAR, on the National Center for Science and Engineering Statistics (NCSES) website. Beginning with the 2007 SED, data on race and ethnicity, sex, and citizenship status of doctorate recipients are no longer available within WebCASPAR. The following variables remain available for analysis: academic institution (both the doctorate-granting institution and the baccalaureate-granting institution of doctorate recipients), institutional control (public versus private), highest degree awarded, state, and academic discipline (both detailed and broad categories). Reducing the number of SED variables available in WebCASPAR is a part of a larger program to strengthen the confidentiality protections applied to SED data while still meeting the needs of SED data users.

To continue to provide data users with access to race and ethnicity, sex, and citizenship data from 2007 onward, NCSES developed another data access tool, the SED Tabulation Engine. This tool is designed to display estimates that do not disclose personally identifiable information in tables using race and ethnicity, sex, or citizenship variables. It provides users with the ability to generate statistics using all of the SED variables previously available in WebCASPAR except baccalaureate institution and the highest degree awarded by those institutions.

Restricted access
Access to restricted data for researchers interested in analyzing microdata can be arranged through a licensing agreement. For more information, see the NCSES Licensing Page at

Contact Information

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For additional information about this survey, or the methodology report, please contact:

Kelly Kang
Project Officer
Human Resources Statistics Program
National Center for Science and Engineering Statistics
National Science Foundation
4201 Wilson Boulevard, Suite 965
Arlington, VA 22230
Phone: (703) 292-7796