As part of our effort to characterize the community that is supported by NIH, we looked at the degrees held by NIH-supported principal investigators (PIs) and whether the composition of that population has changed over the years. As you can see below, ~70% of PIs on NIH research project grants hold a PhD, and this proportion has remained steady for the past 25 years. Most of the remaining PIs have either MD or MD/PhD degrees, with a small percentage unknown or holding other advanced degrees (for example, DVM, DDS, and DMD). The percentage of MDs has declined over the years from ~20% to around ~17%, while the percentage of PIs with a MD/PhD degree has increased from ~8.5% to almost 11% in the same timeframe.
The total number of PIs has increased in this timeframe, and the range of NIH training and career development awards has evolved (see details of specific programs). Notably, we established several new career development awards for clinicians pursuing patient-oriented research in the late 1990s. It seems, however, that the system is remarkably stable. It will be interesting to see if these proportions remain stable over the course of the next few years as science continues to advance and translational research receives emphasis through the National Center for Translational Sciences (NCATS). Meanwhile, we’ll be taking a look at these data and others in our quest to model the future of the biomedical workforce. We’re going to be busy!