Working towards your thesis but struggle to select the best type of PhD thesis? Learn about the main types and benefits of doctoral dissertation types!
Do you know hat is the best type of thesis for your research? I didn’t know until the second year of my PhD program. Deciding what’s the best for your PhD degree isn’t easy, as it will have many implications, from how you’ll structure PhD thesis and through to how you approach the preparation for the thesis defense during PhD viva voce.
Ultimately, agreeing on the type of thesis you’ll compile in due course of your research journey early with your supervisor has many benefits. It gives you clarity of where you’re heading, reduces the anxiety associated with writing your thesis, and gives you a point of reference for easier decision making.
But what are the most popular types of a PhD thesis that you may consider for your PhD degree? Let me elaborate on this a bit more.
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What is a PhD thesis?
Once you get admitted to a graduate school for a PhD degree, your ultimate goal is to conduct exciting and novel research. The output of your work needs to be presented in the form of an academic report – a PhD thesis, aka. doctoral dissertation.
The specific requirements for the format of the doctoral dissertation vary depending on whether you do your research in the United Kingdom, the United States or another country, the university you’re enrolled on, and even the type of doctoral degree you’re undertaking. The expectations will also vary between life sciences, natural sciences, social sciences, engineering and so on. Therefore, the key thing that you need to do as a PhD researcher is to check how your university defines a PhD thesis.
Here are several definitions for doctoral dissertation:
“PhD thesis (ˌpiːˌeɪtʃˈdiː ˈθiːsɪs) [is] a research thesis written and submitted by a student wishing to be awarded a PhD” Collins Dictionary
“Thesis / Dissertation [is] a long piece of writing on a particular subject, especially one that is done for a higher college or university degree” Cambridge Dictionary
“Thesis [is] a scholarly essay defending some proposition, usually a dissertation submitted for an academic degree” Oxford Reference
From the above references, you can conclude that thesis is a piece of academic work that contributes to the academic body of knowledge and is presented by someone wishing to obtain a higher education degree, such as EngD or PhD degrees.
Have you come across an interesting definition of a thesis? Share it with others in the comment or tag us @MotivatedAcademic on social media.
Is a doctoral dissertation equivalent to a PhD thesis?
In most cases, the terms PhD thesis and doctoral dissertation are used interchangeably. However, some sources indicate that there may be some differences.
For example, the Royal Literary Fund indicates that you complete the dissertation during your masters, whereas you write your thesis during your PhD degree. The Best Masters Degree portal claims, however, that it is vice versa.
I would say that a doctoral dissertation is equivalent to a PhD thesis – after all it’s just a term and what really matters is what contribution you’ll make and present in your work and during your viva voce examination.
What are different types of PhD thesis?
Now that we clarified what a doctoral dissertation is, let’s discuss what are the different types of PhD thesis. And there are two key types that you can come across: a monograph PhD thesis and a paper-based PhD thesis.
A monograph PhD thesis is essentially a 150-300 book that you produce during your research programme. It is still the most common format for a doctoral dissertation across all fields of science and engineering.
A paper-based PhD thesis is essentially a collection of academic papers that you published during your PhD. According to Lund University, the paper-based PhD thesis “is predominantly adopted in the hard sciences and engineering, but it does also occur in some disciplines in the social sciences and humanities.”
What is a monograph PhD thesis?
A monograph PhD thesis is a coherent piece of academic writing focusing on the key outcomes of your research project. It is written by you, as the sole author, and can be later published in the form of an academic book.
It follows a conventional structure including:
- introduction
- literature review
- methods and materials
- results
- discussion
- conclusions
As you can see, this type of PhD thesis follows a similar structure to a research paper, but the results chapter will include multiple subsections that will correspond to the stages of your research.
What are benefits of a monograph PhD thesis?
The main benefit of producing a monograph PhD thesis is the fact that you can publish it as a sole-authored book after you defend your viva voce. It’s a nice feeling to see the amount of work that you’ve done over 3-5 years printed in a coherent volume!
Importantly, when you decide to write a monograph, you’re in control of how it looks like and how you structure it (within the university regulations of course!). Your progress is also not hindered by the time you need to wait for the peer-reviewers to comment on your work when you submit your work as academic articles to a journal.
With that being said, I strongly advise you to publish your work during your PhD – it comes in handy when you apply for postdoc or other higher education opportunities once you’re done with your graduate school work.
What is paper-based PhD thesis?
A paper-based PhD thesis, also known as an article-collection thesis, depends on your ability to publish your work during your PhD.
With such a thesis, all of your research chapters will be accepted for publication in respected academic journals. Your literature review can also be published as a review paper.
As opposed to a monograph PhD thesis, the chapters of your thesis will be co-authored by your supervisors, in most cases. It is important to emphasise that if you want to be able to include a specific paper in your thesis, you need to be the first author or be the major contributor to that work – I won’t discuss the ethics of publishing and order of authors here, but please be aware of this.
A paper-based thesis does usually follow the following structure:
- introduction
- literature review or review paper
- research paper #1
- research paper #2
- research paper #3
- …
- general discussion
- conclusion
As you can see, the structure of an article-collection PhD thesis is fairly simple. As a rule of thumb, you need to produce at least 3 research papers for this type of But you need to do more than just bolt your academic papers together in the form of a written report.
What I mean by this is that you need to demonstrate that the papers from your doctoral degree have a common thread and you need to explain how they form a coherent piece of work.
Although each subsequent research paper you’ll include in your doctoral dissertation will include results and a discussion section, you still need to include a general discussion section that will discuss the main outcomes of your doctoral degree.
Therefore, don’t make a decision on pursuing a paper-based PhD thesis based on an assumption that it’s the easier route. You need to publish your work first and then do some additional writing to make sure your work is of high quality.
What are benefits of a paper-based PhD thesis?
The ultimate benefit of pursuing a paper-based thesis is the fact that all of your work is already published and easily accessible to other researchers, ideally in open-source journals. It’s also a great portfolio of work when you apply for postdocs!
Your published papers also have undergone a rigorous (I hope!) peer-review process. This means that it’s less likely to have any errors or omissions. It makes the life of your examiners easier, although be careful here. The fact that you’ve published your work doesn’t automatically award you a PhD degree and make your thesis defense any easier. You still need to defend and justify your work.
Also, I find paper-based PhD theses more structured and easier to manage. I did one myself, and it was just natural for me to move from one “mini” project to another during my PhD program.
Monograph or paper-based PhD thesis? How to decide?
As I mentioned above, the sooner you decide on the type of PhD thesis you’d pursue in your programme, the better because you’d be able to plan and develop your work accordingly, as well as start building the structure of your PhD thesis throughout your programme.
Before you make this decision, weigh the advantages and disadvantages of both options and discuss them with your supervisors. More importantly, check the regulations of your graduate school to understand whether you’ve actually got any choice on the types of PhD thesis, whether there’s a predefined one for your degree.
Think about logistics too.
Will you be able to publish at least 3 research papers during your PhD programme (P.S. I think it’s a bare minimum for each PhD!)?
Do you like to close one chapter before moving to another or maybe you like to work on 2-3 things simultaneously?
Do you want to pursue a career in higher education? If yes, what’s preferred in your research area – monographs or research papers?
Or maybe your ambition is to publish a leading monograph in your research area?
There are lots of considerations to be made at this point, but make sure you decide early to leave yourself time to pivot if necessary.
Conclusion
Deciding on the type of thesis you’ll pursue in your degree will dictate the way you will manage your work and may have implications on your viva voce examination, and even further career.
The earlier you do this the better! But make sure you weigh your options first. Check what it is that you want to do after your PhD program and which type of PhD thesis will support you better in this endeavour.
Either way, I trust you’ll enjoy writing your PhD thesis as much as I did! By the way, I wrote my thesis as a compilation of 9 academic papers, including 1 review paper and 8 research papers published in prestigious journals over just 2.5 years.
Want to know how I did this? Check out the Paper Writing Masterclass!
