How long do you think is an appropriate time for students to commit to their PhD? If you ask around, the perceived time range varies quite a bit, 3-4 years, 4-6 years, or even double-digit years. If we can't agree on the time length of a doctoral degree (like Med, Pharmacy, and Law school), there must be other cemented parameters that guide students to graduation? .... Right....?
How do you know when you are ready to graduate?
Most STEM doctoral students travel a similar path. They conduct research until their project is complete, then after writing a thesis and defending it, they are conferred with the title of "Doctor." The question is, when does one actually "complete" a research project? Research is never done. One question is answered, which leads to another question, which leads to another and to another.
So how does one judge if a graduate student's work is finished? I tweeted out this question sometime ago and received various answers. Most responses were number of publications, completion of proposal aims, or the amount of years in the program. A few other less common answers were, "vibe," "loss of funding," "up to the PI" and....
So let's break the most common answers down:
Number of publications: Many programs require 1-2 publications for a student to graduate. Often, this is considered a fair. Other times, it puts the student at a disadvantage. This parameter neglects to normalize the support systems within the lab. Some students have no lab-techs, post-docs, or collaborators, meaning that publishing is a much more arduous task than their counterparts. If a student is lucky, they receive a project that is low-risk or partially finished, while other students work on high risk projects for years without a payout.
Completing proposal aims: At the surface, this seems to be an equitable stipulation for graduation. But often, students write proposals off-topic, rendering this parameter impossible. Frequently, projects evolve and take the student in another direction than their proposal. If they veer off path for the sake of science exploration, should they be still held to the same proposal they wrote years ago?
Years in program: Not all projects are created equal, and not all students put in the same effort over the same period of time. However, I argue that putting a time cap drives productivity, encourages streamlined research, and motivate PIs to support their students in finishing their projects.
Graduate student labor.
Graduate students are cheap labor, most making about $30,000 a year. PIs are reluctant to allow students to graduate, thereby forfeiting a valuable resource. Besides the project a student is working on, a grad student is also expected to train incoming lab members, maintain lab equipment, contribute to lab chores, and work on side projects other than their thesis.
We have to ask ourselves if more years in the same program with the same mentor is beneficial to a student's education and training. Is a seventh-year student still learning from their mentor, or are they underpaid employees receiving typical on-the-job training? Furthermore, extending a student's PhD training can certainly have setbacks.
Time at school should not be taken for granted.
A long PhD can have detrimental effects on a students' life and career:
From the many student-PI conflicts I've seen, it's naive to believe the current system of arbitrary graduation guidelines is working. To give more protection to graduate students, I propose two policies: (1) A 4-year time cap for students with a Master's degree or a 5-year time cap without a Master's degree, and (2) salary raises for students throughout the program.
Providing a time cap.
With no time cap, graduate students are encouraged to work on non-thesis research and to tackle high-risk projects that are likely to not pan out. A time cap can motivate both the student and the mentor to come up with a practical project plan and remain focused at the proposed thesis work needed for graduation. Consider Parkinson's Law which states that work will expand to fill the time allotted. Under this principle, a student will finish their dissertation research in four years if given a four year time limit. Without the time limit, a student will linger in the program until an external factor (funding, unhappiness, or a job offer) influences them to wrap up their project.
However, there are plenty of reasons to fight against a time cap: variability between disciplines, discrepancies in work ethic, and neurodiversity of students. This is why I recommend a 4-5 year time cap with an opportunity to extend. Extensions can be offered to students with disabilities, or if a student, PI, and thesis committee mutually agree staying in the program is beneficial.
Demanding raises for long-standing students
Paying senior students more money is another way to ensure equity to graduate students. Senior students take on more responsibility and are [usually] more skilled. Granting raises rewards students for more time in the program and also removes the cheap labor bias.
It's not all the PIs fault.....
It's easy to blame the thesis advisor. But if PIs aren't given the proper tools and support system to keep a lab running smoothly, can we blame them for wanting to keep students on longer? Here's a few ways institutions can support PIs more:
I am aware that many European Universities have time limits. This post is written by an American graduate student whose program has a loose 7-year limit. I am a fourth-year student who intends to graduate during my fifth year. Even with three pubs (one published, one submitted, and one underway) and a Master's degree, I receive pushback that I should stay well into my 6th year. I'm convinced that more time in my PhD will not further my education or career prospects, but I am certain that it will affect my financial and mental health.