In recent years, a crisis has been building in academia. Traditionally, the PhD has been a qualification meant to prepare people for a career in academic research. However, the number of doctorates has been increasing enormously – a growth of nearly 40% between 1998 and 2008, with little corresponding increase in the number of permanent academic jobs. 
Most of these students will end up being employed in other sectors, but that is not what they have in mind. Recent UK and international surveys have found that around 60% of PhD students aspire to a career in academia. [2,3] In contrast, a 2010 assessment by the Royal Society found that only 3.5% of UK PhD students manage to get permanent academic research positions, with just 0.45% becoming professors.  There is little clear data on this in other countries, but it is widely recognised that only a small proportion of PhD graduates will manage to stay in academia in the long term.
Diagram illustrating the career paths of UK PhD graduates. 
A recent study undertaken at the University of California, Berkeley indicates how these statistics may be impacting on the health of students. A survey of their graduate students found that 47% of the PhD students were depressed.  This is much higher than the average rate of depression in the United States of 6.6%.  To understand the significance of this result, one must understand that depression is more than just feeling unhappy for a few days every now and then. It can involve feeling sad or hopeless for weeks or months at a time, not getting any enjoyment out of anything, or losing motivation to even get out of bed and face the day. Depression can be disabling and isolating, sometimes preventing people from functioning in social or work situations, and often requiring medical attention. 
The measured prevalence of depression in UC Berkeley PhD students has received considerable attention in the media, but there is another important result that has had much less coverage: the study also assessed the predictors of depression in the students. One of the top indicators of depression was how they felt about their career prospects. A couple of examples of their comments highlight this result:
“The largest source of anxiety for me is my post-grad job outlook. It is tremendously uncertain, and thus fear-inducing.”
“I cannot tell you how much better my life is now that I know I have a lucrative non-academic job waiting for me at the end of this journey.”
Looking again at the statistics on how many PhD students want to stay in academia and how many manage to do so, this makes some sense. Many of them will be going through the process of reassessing their abilities and their futures. For some, this will be accompanied by a strong sense of failure and significant damage to their self-esteem.
There are lots of ideas as to how this situation could be addressed, as discussed in a recent article in Nature . The ideas can largely be summarised by three broad options:
Better educate prospective and current PhD students about their career prospects. Removing misconceptions about the academic career path before enrolment would help to ensure that people undertake PhDs for the right reasons. Encouraging current postgraduates to consider alternative careers at an earlier date would shorten the period over which they struggle towards what is usually an unrealistic goal.
Change the PhD to better prepare graduates for careers outside academia. If most PhD students end up leaving academia, then it may make sense to reflect this in the nature of the course, making them feel better able to do other jobs. This may also remove some of the stigma that currently comes with leaving academic research. However, it could disadvantage the students who still choose to stay in academia when competing against graduates who did a more traditional PhD.
Reduce the number of PhD students. As the PhD is primarily meant to train people in academic research, some other qualification could better prepare students for the more likely possibility of working outside academia. These qualifications could be Master’s courses, or we could develop a longer course that imparts the same transferable skills as a PhD, but in a more focused way. As PhD students are currently the workhorses of academic research, this option would likely reduce the amount of research carried out – this could be partially addressed by redirecting funds to pay for more post-PhD positions.
There is little objection to better educating students about the academic career path, but more drastic changes may be needed. Suggestions about how the PhD could be changed, or even replaced, have been met with criticism by many academics. However, if the results of the UC Berkeley study are reflective of the wider postgraduate community, then we may have a global health imperative to take a risk and break from the traditional academic education system.
James Tarlton is a PhD student at Imperial College London, developing ion traps for quantum computing applications. His primary global health interests are mental health and food security.
 Cyranoski, David et al. “The PhD factory”. Nature (2011): 472, 276-279.
 Postgraduate Research Experience Survey 2015, The Higher Education Academy, 2015, https://www.heacademy.ac.uk/resource/postgraduate-research-experience-survey-2015. Postgraduate Research Experience Survey 2013, The Higher Education Academy, 2013, https://www.heacademy.ac.uk/postgraduate-research-experience-survey-pres-2013. Postgraduate Research Experience Survey 2011, The Higher Education Academy, 2011, https://www.heacademy.ac.uk/resources/detail/postgraduate/PRES_2011_report.
 Russo, Gene. “Aspirations and anxieties”. Nature (2011): 475, 533-535.
 The Scientific Century, The Royal Society, 2010, https://royalsociety.org/~/media/Royal_Society_Content/policy/publications/2010/4294970126.pdf.
 Graduate Student Happiness & Well-Being Report 2014, The Graduate Assembly of the University of California, Berkeley, 2015, http://ga.berkeley.edu/wellbeingreport/.
 Behavioral Health Trends in the United States: Results from the 2014 National Survey on Drug Use and Health, The Substance Abuse and Mental Health Services Administration, 2015, http://www.samhsa.gov/data/sites/default/files/NSDUH-FRR1-2014/NSDUH-FRR1-2014.htm.
 The National Health Service, “Clinical Depression”, http://www.nhs.uk/conditions/depression/Pages/Introduction.aspx.
 Goulding, Julie et al. “How to build a better PhD”. Nature (2015): 528, 22-25.