Significant gaps exist -- by demographic groups and disciplines -- in who finishes Ph.D. programs. Generally, foreign, male, and white students are more likely to earn their doctorates after 10 years than are their counterparts who are American, female or minority.
While the patterns hold over all, they aren't the same for all disciplines. Black Ph.D. students, for example, are tied with white students in having the highest completion rates for Ph.D.'s in the life sciences, but lag in completion of engineering programs.
The data and analysis  -- being released today -- come from the Council of Graduate Schools and make up the largest ever study of completion rates by different demographic groups. (Much of the existing data on Ph.D. students focuses on degrees awarded as opposed to completion rates, potentially masking serious issues in Ph.D. production.) Twenty-four universities provided data on their doctoral students to allow for a broad cross-section of Ph.D.-granting institutions, disciplines and demographics. The study is part of the council's Ph.D. Completion Project,  which aims to identify policies and programs to encourage completion of doctoral degrees.
The project will use the new data as a baseline. Participating graduate schools now plan to start a series of programs designed to encourage completion and to speed it, and the hope is that subsequent data will show improvements.
Here are the figures that show where the graduate schools are starting:
Cumulative Completion Rates for Students Starting Ph.D. Programs, 1992-3 Through 1994-5
|Group||By Year 5||By Year 6||By Year 7||By Year 8||By Year 9||By Year 10|
Many unique factors shape whether an individual graduate student finishes a doctorate or does so in a reasonable time frame. But some of the average gaps may be significant enough, researchers hope, to help graduate schools over time identify better policies. Robert Sowell, director of the Ph.D. Completion Project, said that he was struck by the high success levels of black students in the life sciences and hoped that some factors might be found there that could be replicated in engineering.
One of the most striking gaps was found between international and domestic graduate students, with the former much more likely (67 percent vs. 54 percent) to complete doctorates within 10 years. Many graduate students from outside the United States enroll in science and technology programs, which historically have speedier Ph.D. completion times than do other programs. But even comparing international and domestic students with disciplines factored in, the non-Americans are much more likely to finish.
10-Year Completion Rates by Field and Citizenship
|Math and physical sciences||51%||68%|
Sowell said that a variety of factors could explain these gaps. Many international students have visas with specified time limits, and renewing visas can be complicated and uncertain -- creating real pressure to finish, he said. Further, many of those visas limit the ability of the graduate students to hold jobs, while some American students hold full-time jobs throughout prolonged graduate school careers.
Gaps are also present when examining completion rates by discipline and race/ethnicity.
10-Year Completion Rates by Field and Race/Ethnicity
|Field||African American||Asian American||Latino||White|
|Math and physical sciences||37%||53%||53%||52%|
A similar analysis by gender -- where men overall have higher completion rates -- shows a split by disciplines. Men are more likely than women to finish doctoral programs in engineering, life sciences and mathematics and physical sciences. Women are more likely to finish in the social sciences and humanities.
10-Year Completion Rates by Field and Gender
|Math and physical sciences||52%||59%|
In addition to examining 10-year completion rates, the report also has details on the percentages of graduate students finishing programs within seven years. For instance, of those who complete a Ph.D., 82 percent of men do so within seven years, while only 75 percent of women do. However, the data are not adjusted for leaves that, on average, women are more likely than men to take.
Sowell said that there are many reasons to focus not just on completion but speed to completion. Attrition can be particularly difficult for those who have spent years working on a degree, and universities and other employers of Ph.D.'s are looking for talent, he noted. There is also the matter of cost. "The longer it takes the student, the more it is going to cost the student and the institution," he said.
Fundamentally, it is important for graduate schools to close these gaps in light of larger demographic trends, he said, to keep the supply of academic talent coming. Since future cohorts of graduate students will be less white and less male than current cohorts, Sowell said, "it's a matter of meeting that work force need."
He cited three examples of the kinds of the strategies colleges are trying to increase completion rates:
- Better information going in. One factor many graduate schools believe contributes to high attrition rates is a lack of information about what it means to earn a doctorate. "They don't know what they are getting into," Sowell said. So graduate schools are trying to be more explicit about the demands of their programs and to expose prospective students to just what their lives would be like.
- Dissertation help. More graduate schools are starting a range of programs to help the writing process, he said. "Dissertation boot camps," either as retreats or regular on-campus meetings, are designed to allow Ph.D. students to coach one another while receiving expert advice as well.
- Family leave. More graduate schools are adopting policies to support students who become parents. In some cases, these policies may delay completion, but Sowell said that "the positive thing about the policies would be the completion rates."