Sometimes a PhD (or life outside of it) can be so draining and demanding that it it no longer becomes possible to finish it. There may be any number of reasons why a PhD student can't make it to the end.
Whether you are concerned about drop-out rates, are interested in the likelihood of finishing, or you are thinking about dropping out, the PhD drop out or non-completion rate is surprisingly high and surprisingly variable.
The percentage of students who don't complete their PhD varies hugely; some institutions report as high as 71% and some as low as 9%. The PhD non-completion rate depends on many factors, such as the subject or department you are studying in, your age and whether you have a good mentor.
This is because a PhD is hard in itself, but sometimes the odds might be more stacked against you than you realise.
The difference between dropping out, moving around and failing
There is a difference between dropping out of a PhD (i.e. non-completion) and failing (i.e. not passing a viva or thesis submission). Outright failing a PhD is actually quite low; in the UK Discover PhDs found this to be just 3.3% of students. It's highly likely that you will be requested to make minor, or even major corrections after a viva, but outright failure is quite rare. If you do find yourself in this 3.3%, don't panic that it was all for nothing; Discover PhDs found that 97% were awarded an MPhil (basically equivalent to a 2 year PhD). So essentially, only 3% of 3%, fail fail.
It is not uncommon for students to move around institutions either by pre-arrangement or otherwise. Direct transfers tend to be very uncommon but they do happen. Generally, they would probably need to be a partner institution to begin with. However, some students may start in one place and decide that the department is not a good fit for them; they love doing a PhD but ended that particular one and started a new one at another institution. This is not uncommon and I have known a few students to do this. So although this is viewed as a non-completion, the student themselves still achieved a PhD.
The drop out rate can vary dramatically by institution
The drop out rate varies hugely between institutions and even between departments within the same institution. In some cases the figure is worryingly high; 45% of students drop out of a University of Durham Education PhD, a freedom of information by Palatinate revealed. According to this same data request of 10 UK universities, the drop-out rate varied anywhere from 7-35%; a huge range. In another data request from 14 UK universities by Discover PhDs, the average failure rate across those universities was 19.5%.
What does the failure or drop out rate actually tell you?
A high non-completion rate at an institution, may not always be a bad thing. It could indicate that they are giving opportunities to students who may not otherwise have been able to do a PhD elsewhere. Overall it is likely that these will have a higher drop out rate due to having lower qualifications for example, but there will also be a large proportion that succeed and go on to have a great career.
It may be that the institution has a high diversity of students. International students often have complex funding issues that aren't always sorted out in time, meaning the student has to pull out.
They may have a higher proportion of students who are mature. Mature students often come with extra life commitments, such as financial demands and returning to study may be more challenging than they initially realised. Age could be considered a 'risk factor', though I think you can do a PhD at any age. However being under 26 years of age, increases your chances of success by around 50%, (Groenvynck, Vandevelde and Rossem, 2013) and Vassil and Solvak (2012) also found that being over 30 increased the risk of non-completion.
If an institution has higher standards of achievement, such as more rigorous testing and a stricter review procedure, there may be more students that don't make the grade. Whilst some institutions are more willing to hold their students' hands over the finish line, even almost pushing in some cases, others are less inclined to take this approach.
However on the other hand, a high number of students that fail to receive a doctorate does indicate warning signs, especially if a department or institution is particularly high. It could indicate that there are department-wide issues such as poor staff behaviour, inadequate resources for your subject and/or a lack of communication and engagement.
Institution-wide it could indicate a lack of student support services or even acceptance, particularly for those groups I've mentioned above but also for those with disabilities and short or long term illnesses. Racism, misogyny and colonialism (amongst others) are unfortunately to frequent in academia and make the journey much more difficult for many ethnicities and genders; some universities and departments are much worse than others.
It may be that there is so much red tape to wade through to get an issue sorted that students lose the energy to keep going. It may be due to poor university management and a lack of value placed on PhD students. Do talk to others in the place you're interested in studying.
What the literature says about students dropping out?
There are numerous reasons why a PhD student may drop out. These reasons tend to be either by realising a PhD is not for them or that something else is preventing them from continuing or that the university have decided the student is having trouble meeting the requirements of the program. The last reason is not common but it does happen.
According to Groenvynck, Vandevelde and Rossem (2013) the major reasons for dropping out of a PhD are discipline and funding provider. For example, social sciences was the worst performing discipline with a completion rate of just 29.4% compared to 62.4% for those students studying natural sciences.
Conversely, Vassil and Solvak (2012) did not find the same result, but instead pointed to issues surrounding challenging individual circumstances. They noted that they expected that these circumstances are in fact not individual but relate to wider, more general structural problems such as low rates of pay.
Within the discipline of biomedical sciences, Benzon et al (2020) found that having a great mentor (along with working at the same time in an academic field) increased success rates.
In a response to Palatinate, Durham University indicated that a significant proportion of students within a number of disciplines (including Education) are mature students and view this as a reason for a low success rate.
These studies suggest that there is no one cause of dropping out, but instead there may be a unique combination of factors linked to where and what you're studying, the support network you have and your own personal circumstances.
If you're thinking about dropping out, here's something to try
If you're reading this, it's likely that dropping out is on your mind. To be honest it's probably crossed every PhD student's mind at some point!
Ultimately only you can make the decision about whether to step aside from your PhD. I want to talk about quitting a PhD in another post, but for now I want to start by asking you a question; is it the PhD work itself that makes you want to quit or is it how/where/when you're doing the PhD?
Try to separate out the specific work you are doing and the field you work in from the department, the institution, where you're at in life, where you're living etc.
Then maybe this will help you whether a PhD just isn't for you, or there is something else that is getting in the way. If you decide on the former, it may be best to wrap up and choose a new path; be honest with your supervisor and don't aim to burn any bridges. But do talk it through thoroughly with others who are best to advise you; don't let a lack of confidence in your own abilities or isolation get the better of you. You've got this! Sometimes a break of a period of time, or a slight change may re-ignite your passion or make best use of your skills.
If it's the second, then that's actually a lot more challenging because the passion for the PhD is there, it's that life has dealt you a rough hand for whatever reason. But it may be potentially solvable. This is not the post to delve into these issues, but know that you are not alone, and I would advise talking to someone who may be able to help and provide you with support.
To wrap up, as I said at the beginning; a PhD is hard. It's a challenge and there will be many ups but also many downs. Abraham Lincoln, puts it well:
"I pass my life in preventing the storm from blowing down the tent, and I drive in the pegs as fast as they are pulled up."
If you are struggling in your PhD, are questioning its worth or are lacking motivation to finish, please reach out by email;
I can't promise a prompt reply, but I'll do what I can to help.
If you are just in the neighbourhood looking for some inspiration, then my post on how to keep motivated may be just the ticket 😉