Academic degree
Doctoral degrees or doctorates, such as the Doctor of Philosophy degree (PhD or DPhil) or Doctor of Education (EdD or DEd) are awarded following a programme of original research that contributes new knowledge within the context of the student's discipline. Doctoral degrees usually take three years full-time. Therefore, in the UK it may only take seven years to progress from undergraduate to doctoral level – in some cases six, since having a Master's is not always a precondition for embarking on a doctoral degree. This contrasts with nine years in the United States, reflecting differences in the educational systems.
Graduate science education in the United States
Depending on the specific field of study, completion of a PhD program usually takes four to eight years of study after the Bachelor's Degree; those students who begin a PhD program with a master's degree may complete their PhD degree a year or two sooner. As PhD programs typically lack the formal structure of undergraduate education or related professional degree education (JD, MD, DVM, MBA, etc.), there are significant individual differences in the time taken to complete the degree. Many U.S. universities have set a ten-year limit for students in PhD programs, or refuse to consider graduate credit older than ten years as counting towards a PhD degree. Similarly, students may be required to re-take the comprehensive exam if they do not defend their dissertations within five years after submitting it to their self-chosen dissertation advisors. Overall, 57% of students who begin a PhD program in the US will complete their degree within ten years, approximately 30% will drop out or be dismissed, and the remaining 13% of students will continue on past ten years.