The research workforce for the biomedical sciences is broad and diverse. It is primarily composed of individuals who hold Ph.D.s, though it also includes individuals with broader educational backgrounds, such as those who have earned their M.D.s from the Medical Scientist Training Program (MSTP) or other dual-degree programs. In addition, some individuals with M.D.s but without Ph.D.s have acquired the necessary training to do basic biomedical research. But although the analysis in this report should ideally be based on the entire workforce just defined, there are no comprehensive databases that identify the research activities of M.D.s. Therefore much of the analysis will be restricted to holders of a Ph.D. in one of the fields listed in Appendix C, with the assumption that an individual’s area of research is related to his or her degree field. A separate section in this chapter is devoted to M.D.s doing biomedical research, and an analysis of the clinical research M.D. workforce is given in Chapter 4.
It should also be noted that the discussion in this chapter does not include individuals with doctorates in other professions, such as dentistry and nursing even if they hold a Ph.D. in addition to their professional degrees. However, there are important workforce issues in these two fields, and they are addressed separately in Chapters 5 and 6 of this report.
The major sources of Ph.D. researchers in the biomedical sciences are the U.S. research universities, but a substantial number also come from foreign institutions. These scientists, whether native or foreign born, enter the U.S. biomedical research workforce either directly into permanent assignments or via postdoctoral positions.
For most doctorates in the biomedical sciences, interest in the field begins at an early age, in high school or even grade school. In fact, almost all high school graduates (93 percent) in the class of 1998 took a biology course—a rate much greater than other science fields, for which the percentages are below 60 percent.1 Even in the early 1980s, over 75 percent of high school graduates had taken biology, compared to about 30 percent for chemistry, which had the next-highest enrollment. This interest in biology continues into college, with 7.3 percent of the 2000 freshman science and engineering (S&E) population having declared a major in biology. This was an increase from about 6 percent of freshman majors in the early 1980s but less than the high of about 9.5 percent in the mid-1990s. Overall, the number of freshman biology majors increased from about 50,000 in the early 1980s to over 73,000 in 2000.2 In terms of actual bachelor’s degrees awarded in the biological sciences, there was a decrease from about 47,000 in 1980 to 37,000 in 1989 and then a relatively sharp rise to over 67,000 in 1998. This was followed by a slight decline to about 65,000 in 2000.
There is attrition, however, in the transition from undergraduate to graduate school. In the 1980s and 1990s only about 11,000 first-year students were enrolled at any one time in graduate school biology programs. Percentage-wise, this loss of students is greater than in other S&E fields but is understandable: many undergraduates obtain a bachelor’s degree in biology as a precursor to medical school and have no intention of graduate study in biology per se. The total graduate enrollment in biomedical sciences at Ph.D.-granting institutions grew in the early 1990s and was steady at a little under 50,000 during the latter part of the decade. However, there was some growth in 2001, of about 4 percent over the 2000 level, and the growth from 2000 to 2002 was about 10 percent (see Figure 2-1), driven in large part by an 18.9 percent increase of temporary residents. The overall growth may not continue, however, as the first-year enrollment for this group slowed from 8.9 percent in 2001 to 3.0 percent in 2002.
The tendency for graduate students to receive a doctorate in a field similar to that of their baccalaureate degree is not as strong in the biomedical sciences as it is in other fields, where it is about 85 percent. From 1993 to 2002, some 68.4 percent of the doctorates in biomedical programs received their bachelor’s degree in the same field and another 8.4 percent received bachelor’s degrees in chemistry.3 This relative tendency to shift fields should not be viewed negatively, however, as doctoral students with exposure to other disciplines at the undergraduate level could provide the opportunity for greater interdisciplinary training and research.
Advances in biomedical research and health care delivery, together with a strong economy in the 1990s and increased R&D support, drove the growth of academic programs. Total academic R&D expenditures in the biological sciences, in 2001 dollars, began to rise dramatically in the early 1980s. They started from a base of about $3 billion and reached a plateau of almost $5 billion in the mid-1990s. As seen in Figure 2-2, this increase of about $2 billion was virtually repeated in the much shorter period from the late 1990s to 2002, as the NIH budget doubled. Although the increases in R&D support during the earlier period were reflected in the increased graduate enrollments of the 1980s and mid-1990s (seen in Figure 2-1), the enrollments since then have not kept pace with fast-growing R&D expenditures. This