Doctoral degrees are designed to train research scholars and, in many cases, future college and university faculty members. Doctoral degrees certify that a student has demonstrated the he or she possesses a minimum level of expertise in scholarly research in a particular discipline.
At the doctoral level, the PhD (doctor of philosophy) is the most common degree awarded in academic disciplines. Other doctoral degrees are awarded primarily in professional fields, such as education (Ed.D. or doctor of education) and business administration (D.B.A. or doctor of business administration). Doctoral programs involve advanced coursework, seminars, and the writing of a dissertation that describes the student’s own original research, completed under the supervision of a faculty adviser.
A comprehensive examination is given, usually after three to five years of study and completion of all coursework, and when the student and adviser agree that the student is ready. This exam is designed to test the student’s ability to use knowledge gained through courses and independent study in a creative and original way. Students must demonstrate a comprehensive understanding of their chosen field of study. Successful completion of this examination marks the end of a student’s coursework and the beginning of his or her research.
PhD degrees are awarded to students who complete an original piece of significant research, write a dissertation describing that research, and successfully defend their work before a panel of faculty members who specialize in the discipline. This may take an additional two to three years of work. Therefore, earning a PhD degree may take from five to eight years beyond the bachelor’s degree, depending on the field of study.
In the United States, you will find a variety of nontraditional doctoral programs; these programs might have very different types of requirements from traditional programs. Prospective students should be sure of what is required to enter any program they are considering, and what is required to obtain the degree. This information is usually available from university catalogs and Web sites or directly from individual departments.
Research Doctorate Programs
The research doctorate is the highest earned academic degree in the United States. It is always awarded for independent research at a professional level in either academic disciplines or professional fields. Research doctorates earned at accredited institutions are not awarded merely for completing coursework, professional preparation, or for passing examinations.
Doctoral studies may begin after a student completes a bachelor’s or a master’s degree. In some subjects it is customary to begin a program that will eventually lead to a doctorate degree immediately upon receiving a bachelor’s degree. However, in other subjects it is common to earn a master’s degree before enrolling in a PhD program.
Regardless of a student’s entry point, doctoral studies typically require three stages of academic work. The first stage involves completing an introductory course, a seminar, and laboratory work along with passing written examinations, usually called “writtens” or “comprehensives.” If a student is successful at this stage he or she is permitted to proceed with doctoral studies, which is known as advancement to candidacy. If the student is not successful then he or she withdraws from the program, in some cases with the possibility of earning a master’s degree. The first stage is often longer for students that do not already possess a higher degree.
The second stage of PhD degree work consists of a set of advanced seminars and consortia during which the student selects a subject for a dissertation, forms a dissertation committee, and plans his or her research. American educators call the doctoral thesis a dissertation to distinguish it from lesser theses. The dissertation committee typically consists of three to five senior faculty in the student’s research field, including his or her academic adviser. They do not necessarily have to be from the student’s own university. Once the student has developed and presented a research design acceptable to his or her adviser and committee, the independent research phase begins.
Dissertation research and writing can take anywhere from one to several years depending on the topic selected and the research work necessary to prepare the dissertation. When an academic adviser is convinced that a student’s dissertation is satisfactory, that student presents and defends his or her dissertation before an academic committee. The defense consists of an in-depth oral examination before the committee, which may involve explaining and justifying his or her research findings. A successful defense of a dissertation results in the awarding of a doctoral degree.
Some doctoral programs may include additional requirements such as fieldwork or teaching-related credentials. All doctoral programs require that certain technical skills be mastered during the first stage, including foreign languages (ancient or modern), mathematical and computer skills, or other specialized professional competencies relevant to the field being studied.
The number of years required to complete a research doctorate in the United States varies by subject and the course load a student is willing to assume. The median time frame for earning a bachelor’s degree to earning a research doctorate, for students continuously enrolled, is (in academic years):
Time to degree for academic disciplines:
Humanities: 8 and one-half years
Life Sciences: 7 years
Mathematics: 7 years
Physical Sciences: 7 years
Social Sciences/Psychology: 7 and one-half years
Time to degree for professional and applied fields:
Business and Management: 7+ years Education: 8+ years
Engineering: 6 and one-half years
Other Professions: 8+ years
The median number of full-time enrollment years for all fields is just over seven. This means that (when added to the average of four to five years for a bachelor’s degree) U.S. citizens who earn an American research doctorate have spent around 11 or more academic years in school as full-time students and researchers. During that time they are in structured and supervised programs, not on their own, and they do not benefit from government stipends or from any legal privileges permitting them to enjoy protected student status.
Recognized Research Doctorates
The most popular research doctorate title awarded in the United States is the Doctor of Philosophy (PhD). However, there are a number of other doctoral titles from which scholars can choose. All have similar content requirements.
The U.S. National Science Foundation (NSF) recognizes the following degrees as equivalent to a PhD.:
Doctor of Arts (D.A.)
Doctor of Architecture (D.Arch.)
Doctor of Applied Science (D.A.S.)
Doctor of Business Administration (D.B.A.)
Doctor of Chemistry (D.Chem.)
Doctor of Criminal Justice (D.C.J.)
Doctor of Comparative/Civil Law (D.C.L.)
Doctor of Criminology (D.Crim.)
Doctor of Environmental Design (D.E.D.)
Doctor of Engineering (D.Eng.)
Doctor of Environment (D.Env.)
Doctor of Engineering Science (D.E.Sc./Sc.D.E.)
Doctor of Forestry (D.F.)
Doctor of Fine Arts (D.F.A.)
Doctor of Geological Science (D.G.S.)
Doctor of Hebrew Literature/Letters (D.H.L.)
Doctor of Health and Safety (D.H.S.)
Doctor of Hebrew Studies (D.H.S.)
Doctor of Industrial Technology (D.I.T.)
Doctor of Library Science (D.L.S.)
Doctor of Music (D.M.)
Doctor of Musical Arts (D.M.A.)
Doctor of Musical Education (D.M.E.)
Doctor of Ministry (D.Min./D.M.)
Doctor of Modern Languages (D.M.L.)
Doctor of Music Ministry (D.M.M.)
Doctor of Medical Science (D.M.Sc.)
Doctor of Nursing Science (D.N.Sc.)
Doctor of Public Administration (D.P.H.)
Doctor of Physical Education (D.P.E.)
Doctor of Public Health (D.P.H.)
Doctor of Professional Studies (D.P.S.)
Doctor of Design (Dr.DES.)
Doctor of Religious Education (D.R.E.)
Doctor of Recreation (D.Rec./D.R.)
Doctor of Science (D.Sc./Sc.D.)
Doctor of Science in Dentistry (D.Sc.D.)
Doctor of Science and Hygiene (D.Sc.H.)
Doctor of Science in Veterinary Medicine (D.Sc.V.M.)
Doctor of Sacred Music (D.S.M.)
Doctor of Social Science (D.S.Sc.)
Doctor of Social Work (D.S.W.)
Doctor of Education (Ed.D.)
Doctor of Canon Law (J.C.D.)
Doctor of Juristic Science (J.S.D.)
Doctor of the Science of Law (L.Sc.D.)
Doctor of Rehabilitation (Rh.D.)
Doctor of Juridical Science (S.J.D.)
Doctor of Sacred Theology (S.T.D.)
Doctor of Theology (Th.D.)
You should remember that first-professional doctoral degrees are not research doctorates in those fields. The research doctorate in all such fields is either the Ph.D. or one of the related research doctorates named in the list immediately above. As with master’s degrees, the institution awarding the doctorate has considerable discretion as to the titles it uses for degrees, and thus institutional nomenclature may differ even in the same subject.