According to research from Indiana University Bloomington, half of those currently in pursuit of careers as scientists at higher education institutions will likely abandon those career plans after just five years.

Researchers analyzed more than 100,000 scientific careers over the course of 50 years, discovering steady growth in that period of a temporary workforce of research associates, lab technicians, post-doctoral researchers and other supporting scientists who are hired on a per-project basis.

In comparison, departure rates from the 1960s show that most of those students who pursued careers in science went on to have full careers in scientific academia.

"Between 1960 and 2010, we found the number of scientists who spent their entire career in academia as supporting scientists — rather than a faculty scientist — has risen from 25 percent to 60 percent," said Stasa Milojevic, an associate professor in the IU School of Informatics, Computing and Engineering, who led the study. "There seems to be a broad trend across fields in science: It's increasingly a revolving door."

The data was culled from monitoring tens of thousands of authors who had published their works in top academic journals over the past half-century. Researchers looked at data concerning more than 70,000 names in the field of astronomy; 20,000 names associated with ecology; and 17,000 names appearing in the robotics field. Among those fields, dropout rates were highest for roboticists, while the relatively lowest, yet still high dropout rate was in astronomy.

Milojevic explained that trend as roboticists increasing their earnings potential by switching to the private sector, while astronomers tend to stay put due to limited professional opportunities beyond the university setting.

The research also revealed that there had been a 35 percentage point increase in the number of scientists not credited as a study’s primary author. Researchers call that particular discovery striking, as career advancement in the science field generally hinges on the old adage “publish or perish.”

"Academia isn't really set up to provide supporting scientists with long-term career opportunities," Milojevic said. "A lot of this work used to be performed by graduate students, but now it's typical to hire a 'postdoc' — a position that practically didn't exist in the U.S. until the 1950s but has since become a virtual prerequisite for faculty positions in many fields."

"The core issue is the number of Ph.D.s being produced is much larger than the number of tenure-track jobs," Milojevic said. "Traditional academia works on an apprenticeship model — people trying to reproduce themselves — but this system represents a disconnect with the newer 'industrial model' of science, which requires large teams of specialists with narrow areas of expertise."

The latter group, according to Milojevic, is composed of professionals whose skills are not compensated at the same scale as that of their peers.

Among the solutions to the problem, as suggested by experts, are transforming the metrics used to reward performance at universities or establishing government institutions with an eye toward unadulterated research.

"In the end, I think these issues will need to be addressed at the policy level," Milojevic said. "This study doesn't provide a solution, but it shows that the number of scientists leaving academia isn't slowing down."

The study is published in the journal of the Proceedings of the National Academy of Sciences.