Doctoral Degrees: Aiming for the Top (2/2)

A PhD usually requires at least 3 years of full-time study after a bachelor's degree. Some people first get a master's degree, other do not. PhD candidates must also pass special examinations and carry out original research. Students present their findings by writing a dissertation, a long paper that they have to defend before a group of experts.

Every year, the federal government collects information on research doctorates awarded in the United States. More than 43000 students received a research doctorate in 2005, the most recent year reported.

Close to one-third of those doctorates went to foreign students in the United States on a temporary visa. The largest numbers came from China, South Korea, India, Taiwan and Canada. Most of them studiedengineering, physical science or life science.

The University of Illinois awarded the largest number of doctorates to foreign students. The other universities in the top five were Purdue, Ohio State, Texas A&M and Pennsylvania State.