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Preparing For Your Dissertation Defense

By: Derek Jansen (MBA) & David Phair (PhD) . Reviewed By: Dr Eunice Rautenbach | June 2021

P reparing for your dissertation or thesis defense (also called a “viva voce”) is a formidable task . All your hard work over the years leads you to this one point, and you’ll need to defend yourself against some of the most experienced researchers you’ve encountered so far.

It’s natural to feel a little nervous.

In this post, we’ll cover some of the most important questions you should be able to answer in your viva voce, whether it’s for a Masters or PhD degree. Naturally, they might not arise in exactly the same form (some may not come up at all), but if you can answer these questions well, it means you’re in a good position to tackle your oral defense.

Viva Voce Prep: 13 Essential Questions

What is your study about and why did you choose to research this in particular?
How did your research questions evolve during the research process?
How did you decide on which sources to include in your literature review?
How did you design your study and why did you take this approach?
How generalisable and valid are the findings?
What were the main shortcomings and limitations created by your research design?
How did your findings relate to the existing literature?
What were your key findings in relation to the research questions?
Were there any findings that surprised you?
What biases may exist in your research?
How can your findings be put into practice?
How has your research contributed to current thinking in the field?
If you could redo your research, how would you alter your approach?

#1: What is your study about and why did you choose to research this in particular?

This question, a classic party starter, is pretty straightforward.

What the dissertation or thesis committee is assessing here is your ability to clearly articulate your research aims, objectives and research questions in a concise manner. Concise is the keyword here – you need to clearly explain your research topic without rambling on for a half-hour. Don’t feel the need to go into the weeds here – you’ll have many opportunities to unpack the details later on.

In the second half of the question, they’re looking for a brief explanation of the justification of your research. In other words, why was this particular set of research aims, objectives and questions worth addressing? To address this question well in your oral defense, you need to make it clear what gap existed within the research and why that gap was worth filling.

#2: How did your research questions evolve during the research process?

Good research generally follows a long and winding path . It’s seldom a straight line (unless you got really lucky). What they’re assessing here is your ability to follow that path and let the research process unfold.

Specifically, they’ll want to hear about the impact that the literature review process had on you in terms of shaping the research aims, objectives and research questions . For example, you may have started with a certain set of aims, but then as you immersed yourself in the literature, you may have changed direction. Similarly, your initial fieldwork findings may have turned out some unexpected data that drove you to adjust or expand on your initial research questions.

Long story short – a good defense involves clearly describing your research journey , including all the twists and turns. Adjusting your direction based on findings in the literature or the fieldwork shows that you’re responsive , which is essential for high-quality research.

You will need to explain the impact of your literature review in the defense

#3: How did you decide on which sources to include in your literature review?

A comprehensive literature review is the foundation of any high-quality piece of research. With this question, your dissertation or thesis committee are trying to assess which quality criteria and approach you used to select the sources for your literature review.

Typically, good research draws on both the seminal work in the respective field and more recent sources . In other words, a combination of the older landmark studies and pivotal work, along with up-to-date sources that build on to those older studies. This combination ensures that the study has a rock-solid foundation but is not out of date.

So, make sure that your study draws on a mix of both the “classics” and new kids on the block, and take note of any major evolutions in the literature that you can use as an example when asked this question in your viva voce.

#4: How did you design your study and why did you take this approach?

This is a classic methodological question that you can almost certainly expect in some or other shape.

What they’re looking for here is a clear articulation of the research design and methodology, as well as a strong justification of each choice . So, you need to be able to walk through each methodological choice and clearly explain both what you did and why you did it. The why is particularly important – you need to be able to justify each choice you made by clearly linking your design back to your research aims, objectives and research questions, while also taking into account practical constraints.

To ensure you cover every base, check out our research methodology vlog post , as well as our post covering the Research Onion .

You have to justify every choice in your dissertation defence

#5: How generalizable and valid are the findings?

This question is aimed at specifically digging into your understanding of the sample and how that relates to the population, as well as potential validity issues in your methodology.

To answer question this well, you’ll need to critically assess your sample and findings and consider if they truly apply to the entire population, as well as whether they assessed what they set out to. Note that there are two components here – generalizability and validity . Generalizability is about how well the sample represents the population. Validity is about how accurately you’ve measured what you intended to measure .

To ace this part of your dissertation defense, make sure that you’re very familiar with the concepts of generalizability , validity and reliability , and how these apply to your research. Remember, you don’t need to achieve perfection – you just need to be aware of the strengths and weaknesses of your research (and how the weaknesses could be improved upon).

Need a helping hand?

#6: What were the main shortcomings and limitations created by your research design?

This question picks up where the last one left off.

As I mentioned, it’s perfectly natural that your research will have shortcomings and limitations as a result of your chosen design and methodology. No piece of research is flawless. Therefore, a good dissertation defense is not about arguing that your work is perfect, but rather it’s about clearly articulating the strengths and weaknesses of your approach.

To address this question well, you need to think critically about all of the potential weaknesses your design may have, as well as potential responses to these (which could be adopted in future research) to ensure you’re well prepared for this question. For a list of common methodological limitations, check out our video about research limitations here .

#7: How did your findings relate to the existing literature?

This common dissertation defense question links directly to your discussion chapter , where you would have presented and discussed the findings in relation to your literature review.

What your dissertation or thesis committee is assessing here is your ability to compare your study’s findings to the findings of existing research . Specifically, you need to discuss which findings aligned with existing research and which findings did not. For those findings that contrasted against existing research, you should also explain what you believe to be the reasons for this.

As with many questions in a viva voce, it’s both the what and the why that matter here. So, you need to think deeply about what the underlying reasons may be for both the similarities and differences between your findings and those of similar studies.

Your dissertation defense needs to compare findings

#8: What were your key findings in relation to the research questions?

This question is similar to the last one in that it too focuses on your research findings. However, here the focus is specifically on the findings that directly relate to your research questions (as opposed to findings in general).

So, a good way to prepare for this question is to step back and revisit your research questions . Ask yourself the following:

What exactly were you asking in those questions, and what did your research uncover concerning them?
Which questions were well answered by your study and which ones were lacking?
Why were they lacking and what more could be done to address this in future research?

Conquering this part dissertation defense requires that you focus squarely on the research questions. Your study will have provided many findings (hopefully!), and not all of these will link directly to the research questions. Therefore, you need to clear your mind of all of the fascinating side paths your study may have lead you down and regain a clear focus on the research questions .

#9: Were there any findings that surprised you?

This question is two-pronged.

First, you should discuss the surprising findings that were directly related to the original research questions . Going into your research, you likely had some expectations in terms of what you would find, so this is your opportunity to discuss the outcomes that emerged as contrary to what you initially expected. You’ll also want to think about what the reasons for these contrasts may be.

Second, you should discuss the findings that weren’t directly related to the research questions, but that emerged from the data set . You may have a few or you may have none – although generally there are a handful of interesting musings that you can glean from the data set. Again, make sure you can articulate why you find these interesting and what it means for future research in the area.

What the committee is looking for in this type of question is your ability to interpret the findings holistically and comprehensively , and to respond to unexpected data. So, take the time to zoom out and reflect on your findings thoroughly.

#10: What biases may exist in your research?

Biases… we all have them.

For this question, you’ll need to think about potential biases in your research , in the data itself but also in your interpretation of the data. With this question, your committee is assessing whether you have considered your own potential biases and the biases inherent in your analysis approach (i.e. your methodology). So, think carefully about these research biases and be ready to explain how these may exist in your study.

In an oral defense, this question is often followed up with a question on how the biases were mitigated or could be mitigated in future research. So, give some thought not just to what biases may exist, but also the mitigation measures (in your own study and for future research).

#11: How can your findings be put into practice?

Another classic question in the typical viva voce.

With this question, your committee is assessing your ability to bring your findings back down to earth and demonstrate their practical value and application. Importantly, this question is not about the contribution to academia or the overall field of research (we’ll get to that next) – it is specifically asking about how this newly created knowledge can be used in the real world.

Naturally, the actionability of your findings will vary depending on the nature of your research topic. Some studies will produce many action points and some won’t. If you’re researching marketing strategies within an industry, for example, you should be able to make some very specific recommendations for marketing practitioners in that industry.

To help you flesh out points for this question, look back at your original justification for the research (i.e. in your introduction and literature review chapters). What were the driving forces that led you to research your specific topic? That justification should help you identify ways in which your findings can be put into practice.

#12: How has your research contributed to current thinking in the field?

While the previous question was aimed at practical contribution, this question is aimed at theoretical contribution . In other words, what is the significance of your study within the current body of research? How does it fit into the existing research and what does it add to it?

This question is often asked by a field specialist and is used to assess whether you’re able to place your findings into the research field to critically convey what your research contributed. This argument needs to be well justified – in other words, you can’t just discuss what your research contributed, you need to also back each proposition up with a strong why .

To answer this question well, you need to humbly consider the quality and impact of your work and to be realistic in your response. You don’t want to come across as arrogant (“my work is groundbreaking”), nor do you want to undersell the impact of your work. So, it’s important to strike the right balance between realistic and pessimistic .

This question also opens the door to questions about potential future research . So, think about what future research opportunities your study has created and which of these you feel are of the highest priority.

Discuss your contribution in your thesis defence

#13: If you could redo your research, how would you alter your approach?

This question is often used to wrap up a viva voce as it brings the discussion full circle.

Here, your committee is again assessing your ability to clearly identify and articulate the limitations and shortcomings of your research, both in terms of research design and topic focus . Perhaps, in hindsight, it would have been better to use a different analysis method or data set. Perhaps the research questions should have leaned in a slightly different direction. And so on.

This question intends to assess whether you’re able to look at your work critically , assess where the weaknesses are and make recommendations for the future . This question often sets apart those who did the research purely because it was required, from those that genuinely engaged with their research. So, don’t hold back here – reflect on your entire research journey ask yourself how you’d do things differently if you were starting with a blank canvas today.

Recap: The 13 Key Dissertation Defense Questions

To recap, here are the 13 questions you need to be ready for to ace your dissertation or thesis oral defense:

As I mentioned, this list of dissertation defense questions is certainly not exhaustive – don’t assume that we’ve covered every possible question here. However, these questions are quite likely to come up in some shape or form in a typical dissertation or thesis defense, whether it’s for a Master’s degree, PhD or any other research degree. So, you should take the time to make sure you can answer them well.

If you need assistance preparing for your dissertation defense or viva voce, get in touch with us to discuss 1-on-1 coaching. We can critically review your research and identify potential issues and responses, as well as undertake a mock oral defense to prepare you for the pressures and stresses on the day.