Overview 
Survey Design
Survey Quality Measures
Trend Data
Availability of Data
1. Overview (2006 survey cycle) 
a. Purpose
The Survey of Graduate Students and Postdoctorates in Science and Engineering (also known as the graduate student survey or GSS) provides data on the number and characteristics of students in graduate science and engineering (S&E) and health-related fields enrolled[1] in U.S. institutions. NSF uses the results of this annual survey to assess trends in financial support patterns and shifts in graduate enrollment and postdoctoral appointments. The graduate student survey collects data from all U.S. institutions offering graduate programs in all science and engineering fields and specific health-related fields of interest to NIH. This annual survey collects data items at the academic department level. Data include counts of full-time graduate students by source and mechanism of support, by total and by women; part-time[2] graduate students by sex; and citizenship and racial/ethnic background of all graduate students, including first-time students. In addition, the survey requests count data on postdoctorates by source of support, sex, and citizenship, with separate data on those holding first-professional doctorates in the health fields; and summary information on other doctorate nonfaculty research personnel.
b. Respondents
The 2006 graduate student survey was an establishment-based survey of 586 graduate institutions. NSF administers the survey to institutional coordinators at U.S. educational institutions with programs leading to graduate degrees in S&E and health fields. Institutions complete a separate survey form for each department granting S&E or health-related master's or Ph.D. degrees.
c. Key variables
Count data are available by the following:
- Citizenship
- Doctoral nonfaculty research staff
- Enrollment status (full-time versus part-time)
- Field of science, engineering and health
- Level of study (first year, beyond first year)
- Postdoctorate status
- Primary mechanism of financial support (e.g., fellowship, research assistantship)
- Primary source of financial support (e.g., by specific Federal agency)
- Race/ethnicity
- Sex
The following information is also available on the academic institution:
- Academic institution name
- Department
- Geographic location
- Highest degree granted by department (doctorate/master's)
- Institutional control (public versus private)
- Type of academic institution (e.g., historically black college or university, land-grant institution, medical school)
2. Survey Design
a. Target Population and Sample Frame
The target population is all departments with graduate enrollment and postdoctoral employment in science, engineering or health fields at the beginning of academic year 2006–2007 in all academic institutions in the United States that offer doctoral or master's degree programs in any science, engineering or health field. The survey includes data for all branch campuses, affiliated research centers, and separately organized components such as medical or dental schools, schools of nursing, public health, etc.
b. Sample Design
The GSS is a census of all eligible institutions. NSF has surveyed the complete survey universe since fall 1988. From 1984 through 1987, NSF surveyed institutions on a sample basis. The final 2006 survey universe consisted of 707 reporting units at 586 graduate institutions and included 212 master's-granting institutions and 495 reporting units associated with 374 doctorate-granting institutions.
c. Data Collection Techniques
GSS respondents have had the option of option of reporting data using the graduate student survey Web-based data collection system (GSSWeb) since the 1988 survey. In 2006, 644 of the 707 reporting units used the online option. This system provided immediate feedback on the data to the coordinators and departmental respondents, which helped ensure that their data were accurate and complete. Using GSSWeb allowed respondents to upload their own data files, speeding up the reporting process. The remaining responding units chose to report on paper survey forms.
In either version, paper or Web, NSF asked institutional coordinators to review a list of departments and to indicate any changes in their departmental structure, such as departments newly formed, phased out, split, or merged, and to check off any departments that had neither graduate students nor postdoctorates and for which survey forms would therefore not be submitted. NSF used the revised list of departments to track departmental responses.
Institutions completed a separate survey form (paper or Web) for each eligible department either centrally (by the institutional coordinator) or at the departmental level (by a designated respondent). Institutions returned paper forms to the survey contractor for data entry, editing, and tabulation. The survey contractor referred arithmetic errors, inconsistencies across items, and sharp year-to-year fluctuations back to the institutions for correction or clarification.
The survey collects information for the fall of the year in which data collection occurs. In the 2006 survey cycle, the survey forms were mailed in October 2006. Data collection ended in June 2007.
d. Estimation Techniques
Because the survey is a census of eligible departments, no weighting for sampling is necessary. Imputation rather than weighting is used to adjust for unit non-response.
3. Survey Quality Measures
a. Sampling Variability
Because the 2006 survey was distributed to all institutions on the sample frame, there was no sampling error.
b. Coverage
Coverage at the institutional level is good, given that it is relatively easy to identify schools that grant doctoral or master's degrees. At the departmental level, coverage may also be quite good, because institutional coordinators would normally be in a position to identify relevant departments. Coverage problems could arise through incorrect classification of departments with respect to whether they fall within an S&E or health field.
c. Nonresponse
- Unit nonresponse. Of the 707 reporting units included in the fall 2006 survey, 679, or 96 percent, were able to provide at least partial data. At the departmental level, 11,991 departments responded, or 97.2 percent of the 12,320 departments surveyed. A total of 329 departments, or 2.7 percent of the departmental total, required complete imputation. The survey contractor imputed data for completely nonrespondent departments using data from the previous year, where available.
- Item nonresponse. Of the responding departments, 1,177, or 9.6 percent, required one or more data cells imputed. The survey contractor based imputation for missing data elements on the prior year's data, where available. Otherwise, they imputed the missing data elements from data of peer institutions.
d. Measurement
Possible sources of measurement error in this survey are incomplete or erroneous listing of the reporting units, incomplete information and failure to follow survey definitions and instructions.
Institutions may have incomplete information on their students. For example, to the extent that certain types of support—e.g., self-support—are not channeled through the institution, they may be underreported. In addition, institutions are not always able to identify foreign sources of support.
Respondents may not follow instructions regarding definitions of categories. For example, institutions can vary in defining mechanisms of support (e.g., fellowships versus traineeships) or postdocs, and may report students according to the institution's definition rather than the survey's. Similarly, some misreporting of postdoctorates may occur within medical schools with clinicians being reported as postdoctorates. For the purposes of this survey, postdoctorates devote their primary effort to their own research training through research activities or study. The survey generally excludes clinical fellows, unless the primary purpose of the appointment is research training under the supervision of a senior mentor. Additionally, institutions may have difficulty in breaking down financial information by discipline (e.g., a student may be enrolled in one discipline while receiving support from another).
4. Trend Data
NSF has collected data on graduate S&E and health enrollment and postdoctoral appointees since 1966. From fall 1966 through fall 1971, NSF collected data from a limited number of doctorate-granting institutions through the NSF Graduate Traineeship Program, which requested data only on those S&E fields supported by NSF. Beginning with the fall 1972 survey, NSF assigned this data collection effort to the Universities and Nonprofit Institutions Studies Group and gradually expanded the effort during the period 1972–75 to include additional S&E fields and all institutions known to have programs leading to doctorate or master's degree. Due to this expansion, data for 1974 and earlier years are not strictly comparable with 1975 and later data. NSF has made no attempt to inflate the data for 1966–74 to reflect universe totals.
During the fall 1988 survey cycle, NSF tightened the criteria for including departments in the survey universe and reviewed all departments surveyed. NSF considered those departments that were not primarily oriented toward granting research degrees as no longer meeting the definition of "science and engineering." As a result of this review, NSF determined that a number of departments, primarily in the field of social sciences, not elsewhere classified, were engaged in training primarily teachers, practitioners, administrators, or managers, rather than researchers; consequently NSF deleted these departments from the database. NSF continued this process during the fall 1989–2006 survey cycles and expanded it to ensure trend consistency for the entire 1975–2006 period. As a result, these changes reduced total enrollments and social science enrollments for all years.
During the fall 1992 survey cycle NSF revised the definition of "medical schools" to include only those institutional components that are members of the Association of American Medical Colleges. Prior to 1992 tables that reported on "medical schools" included schools of dentistry, nursing, public health, veterinary medicine, and certain other health-related disciplines. Beginning with the 1992 data, the term "medical schools" means only AAMC members. All tables with historical data on medical schools for 1991 and earlier were revised to include data based on the AAMC membership criteria. Consequently data on medical schools in reports starting in 1992 do not match data from reports in earlier years.
Although NSF has attempted to maintain consistent trend data, it has made some modifications in the survey questionnaire to respond to changing issues over the past 30 years. As a result, some data items are not available for all institutions in all years. For example,
- The target population for the survey changed between 1975 and 1979;
- Collection of race/ethnicity data by sex was begun in 1993 and new race/ethnicity categories were introduced in 1999; and
- Graduate student support information changed between 1978 and 1999, with different forms of support and support from specific agencies being asked.
For these reasons, and because institutions may revise their data for earlier years, use only the latest trend data in historical analyses. NSF encourages analysts wishing to do trend analyses not covered in this report to contact the project officer for additional information.
5. Availability of Data
a. Publications
NSF releases the data from this survey annually in Graduate Students and Postdoctorates in Science and Engineering, and includes information from this survey in the SRS publications Science and Engineering Indicators and Women, Minorities, and Persons With Disabilities in Science and Engineering. NSF includes selected data items from this survey for individual doctorate-granting institutions in SRS's Academic Institutional Profiles series (http://www.nsf.gov/statistics/profiles/).
b. Electronic Access
Data from this survey are available from the WebCASPAR data system. Public-use data files in ASCII format are available for the years 1972–2006.
c. Contact for More Information
To obtain additional information about this survey, contact
Footnotes
[1] Graduate students must be enrolled for credit in any science, engineering or health master's or Ph.D. program in the fall of 2006 to be included in the survey. M.D., D.O., D.V.M., or D.D.S. candidates, interns, and residents are counted if they are concurrently working on an S&E master's or Ph.D. degree or are enrolled in a joint medical/Ph.D. program.
[2] Each institution reports full- and part-time students according to their own policies and definitions.
