Point of View: A fair deal for PhD students and postdocs

The total number of graduate students in the biomedical sciences in the US increased from about 30,000 in 1979 to 56,800 in 2009 (data from figure 2 of the Workforce report). The biggest increase was in the number of students supported from NIH research grants to academic investigators. Fellowships include both NIH and non-federal fellowships. The actual numbers are probably higher because the numbers in the table represent those subsets of the total graduate student population that can be easily tracked: for example, some estimates put the number of PhD students at 83,000 (see Table 2). However, I believe that the overall distribution between subsets, and also the relative changes between 1979 and 2009, are roughly correct.

This snapshot (data from Workforce report, p32) shows that 16,000 students started PhDs in 2009, but only 9,000 students received PhDs in 2009: this suggests a completion rate of just 56%. The table also shows that 66% of PhD graduates go on to pursue careers in research. This suggests that just over one-third (66% of 56% = 37%) of those students who start PhDs go on to become scientific researchers in government, academic or industrial laboratories. The Workforce report emphasizes that these data are only approximate; for instance, estimates of postdoc numbers vary between 37,000 and 68,000, and estimates for the number of PhD students vary between 83,000 (shown here) and 56,800 (Table 1). Overall, however, it is clear to me that too many students start PhDs and that, on average, most PhD training programmes are strikingly inefficient at producing PhDs.

A comparison between the Tetrad PhD programme at the University of California, San Francisco (UCSF), the Watson School at the Cold Spring Harbor Laboratory (CSHL) and an average for all PhD programmes shows differences in the proportion of students who obtain PhDs, the average time taken to obtain a PhD, and the proportion of PhDs who remain in research. Some of these differences might be explained by differences in sample sizes and the length of time that has passed since the PhD was obtained. The differences in the proportion of students remaining in research might also be partially explained by UCSF and CSHL recruiting better applicants and/or their reputations helping new PhDs to obtain research positions (rather than being solely due to better training at UCSF and CSHL). Data: UCSF Tetrad: 7 MD–PhD students who started PhDs in this period are not included due to a lack on information on their post-PhD career path. Watson School: Data available at http://www.cshl.edu/images/stories/wsbs/docs/WSBSstats.pdf. Of the ten students who did not obtain PhDs, seven obtained an MS degree. Data for ‘Post-PhD career path’ is for the 52 individuals who obtained PhDs 2002–2008. Average: data from Workforce report, p32.

The number of postdocs supported by federal (NIH) research grants increased significantly between 1980 and 2009, while the number supported by federal training grants and fellowships remained constant (data from Workforce report, pp19–23). The number supported by non-federal grants (such as the American Heart Association and the American Cancer Society) also increased significantly. The number of non-US postdocs also increased dramatically during this period. Note that these numbers differ (in some cases substantially) from other data on postdocs in the Workforce report: while these differences reflect inadequate tracking and enumeration of postdocs, the relative trends are almost certainly correct.