Doctoral thesis

In the general introduction, you describe your view of the current state-of-the-art in your discipline. You highlight gaps in scientific knowledge and introduce an overview of your thesis. The general introduction contains information that readers need to know in order to comprehend the context of your research chapters. A review article may be used as part of the general introduction. In that case, a short general introduction and overview of the thesis has to be added. There is explicitly no minimum length for the introduction; quality is the only criterion.

Each research chapter contains work, demonstrating that you followed the scientific research cycle:

• you identify a gap in scientific knowledge;
• you outline an approach;
• you describe an appropriate collection and analysis of data, or existing relevant databases;
• you reflect on the results within the context of the specific field.

The length and format of a chapter, the scientific depth, the quality of data collection and analysis thereof, should be of a level customary to your specific discipline. For further details, please read the section When can a manuscript be part of my thesis? (bottom of page). There is no requirement for the number of research chapters in a thesis: quality, coherence and your specific contributions prevail over quantity. The guideline is 3 or more publishable chapters, but fewer can be justified, for example, by the extensiveness of the work. We define a publishable research chapter as a (future) publication or a substantial part of a more extensive study.

Where research chapters, and sometimes the general introduction, are collaborative efforts, the general discussion should be your own product. In this final chapter, you reflect with a birds-eye perspective on your research chapters and notable findings. You identify future opportunities for research, and discuss the impact on the research field and society. There is explicitly no minimum length for the discussion; quality is the only criterion.

Your development is typically broader than the scientific content of your research chapters. You can reflect on your broader personal and scientific development in an attachment to your thesis. This is optional and may be used by the Assessment Committee to acquire a complete picture of you, as an academic in training. However, it falls outside your thesis content, and will not be judged by the Assessment Committee. You may use the GSLS PhD Competence Model (see Chapter 5.1) as a guideline to draft this attachment. Examples of such a PhD portfolio can be found here (pdf).

• The degree of your scientific contribution determines whether a manuscript can be part of your thesis. Not your position in the list of authors. Therefore, each chapter of your thesis should explicitly indicate how you have contributed to this work. If relevant, this also applies to the general introduction and discussion. Please find examples of author contribution here (pdf). Detailed contribution definitions can be found here.
• Collection of data only by you is not sufficient in itself for inclusion of a chapter. You should have followed the scientific research cycle (see the section ‘Research Chapters’).
• If you, as part of a team effort, have conducted a crucial part of a larger study, but you are not the first, second or last author, the work can still be included in your thesis, as long as you explain your role in the study. If your contribution to that publication is not sufficient in itself to be a chapter, you may supplement the material with your own relevant work.
• A (publishable) research chapter does not already have to be submitted or accepted for publication in a peer-reviewed journal to be included in the thesis. However, you and your supervisors should strive to publish these chapters in peer-reviewed open-access scientific journals. For manuscripts that are published or will be in the future, you will be (co)author of the respective thesis chapters, in recognition of your scientific work.