PhD Delays

The PhD Gap

Only 50% of Radboud PhDs hand in their manuscript within 5 years*.

The standard PhD contract is 4 years.

We have highlighted a few key underlying factors that contribute to the delay, and that we believe should be looked into further by the Radboud University and Radboudumc:


A significant amount of PhD positions are tied to a obtained grant. In the current competitive research world, receiving such a grant is challenging and calls for ambitious projects. Although important, these projects do not always keep in mind the limited time of a PhD trajectory. The project itself might fit within 4 years, however, fails to take into account any setbacks or unexpected issues, duties such as teaching, and sufficient time for writing the PhD thesis. Research is inherently unpredictable, and this should be taken into account while considering the time or number of employees a project needs. This is currently not adequately done, resulting in projects that are not feasible within the time of the PhD contract.


Many supervisors are experts in their fields, and have immense knowledge on the topic to be pursued in the PhD trajectory. There is however little guidance on how to supervise the process itself. The supervisors often focus on finishing the research project, less than on ensuring that the PhD candidates finish in time. Insufficient time or quality of supervision can lead to significant delays in PhD trajectories. Although not all thesis guidelines specify a number of chapters, supervisors often have their own, sometimes unrealistic, expectation of thesis chapters and voice this to their PhD candidates. This in turn can give PhD candidates the feeling that they should keep working on extra chapters even if their contract has ended.


Possibilities for extensions to finish the PhD project are dependable on the financial situation of supervisors and their department. Hence, of all PhD candidates that would need an extension, only some of them can finish their PhD while being paid while others are unlucky and have to finish their PhD unpaid. This randomness occurs between departments but sometimes even within departments and creates an unfair situation for PhD candidates with regard to the conditions in which they can finish their PhD trajectory

Education vs. Work

PhD trajectories are a 4 year paid education to become an independent researcher. This leads to some tension. PhD candidates are still learning. From the start onwards there is a known endpoint: most often 4 years from the beginning. There also is a final exam: the PhD defense. At the same time the PhD candidate is a paid researcher, hired to finish a certain project. The latter often dictates when the defense can take place, rather than at the point in time the candidate can prove to be an independent researcher.


If you have questions, comments, or input on this overview, feel free to contact us at

We realise these factors are not applicable to all PhDs in the same capacity, we wanted to highlight some of the issues we believe are relatively widespread and can be discussed broadly. However, that does not mean we are not still looking into more specific issues.

Next to this we are still aiming to get more quantitative data, this is a time-consuming process. We are also in contact with the national PhD organisation PNN that is looking into the delay of PhDs on a national level.

*The recent data we do have only covers type 1a PhDs (employee-PhD), this covers 60% of the PhDs at the Radboud, but also misses a large group. As stated we are aiming to get more data, but at least want to underline there is a gap for a significant group of PhDs in Nijmegen.