PhD Viva and Dissertation Defense Questions: A Full Reference List

Tell me about your thesis.

Examiners want the whole argument in two to three minutes — problem, approach, findings, contribution. The trap is going chronological (what you did, then what you found) rather than argumentative (here is the claim I am making and why). Practise a version that leads with the contribution.

What is the central research question, and how did it evolve?

This tests self-awareness. Examiners know questions sharpen over a PhD; they want to see you can articulate the final, precise question and acknowledge, briefly and without apology, how it tightened from the original.

Why did this topic matter enough to spend three to five years on it?

Not a motivation speech — a research-justified answer. What gap existed, why it was worth filling, and what happens if it stays unfilled. Avoid the vague 'this is an underexplored area'; name the specific gap.

What are the three most important findings in your thesis?

Examiners test whether you can rank your own results. Candidates who cannot prioritise look like they have not stepped back from the data. Prepare a short, ordered list and be ready to explain why those three and not others.

What would you change if you were starting again?

This is a maturity question, not a trap. Examiners expect you to have learned something. A strong answer names one or two genuine design choices you would reconsider and says why — without implying the thesis is flawed. Avoid 'nothing' and avoid cataloguing regrets.

How does the thesis hang together as a whole?

Especially relevant for thesis-by-publication formats. The examiner wants evidence that the chapters form an argument, not a collection of studies. Practise articulating the through-line that connects chapter one to the conclusion.

What is the original contribution of this thesis?

The direct version of the central question. Avoid hedged answers ('I hope this contributes to...'). State it as a claim: what is now known, built, or possible that was not before. If your contribution is empirical, theoretical, methodological, or some combination, say which.

How is your work different from [specific author/study]?

Examiners usually have a name in mind when they ask this — someone whose work is close to yours. The answer must be specific: different question, different context, different method, different finding, or a combination. 'I go further' is not enough.

What did you find that was unexpected?

Examiners use this to distinguish genuine inquiry from a project that confirmed what the researcher expected to find. A null result, a pattern that cut across your categories, or a finding that required you to revise your framework — any of these count. Admitting surprise does not weaken the thesis.

If you had to cut the thesis to its single most important contribution, what would you keep?

A prioritisation test. Many candidates have two or three contributory threads; examiners want to know which one the candidate considers load-bearing. Give a direct answer and justify the hierarchy.

How significant is this contribution — who needs to know about it?

Examiners probe scope: is this a local empirical result or a broader theoretical claim? Be honest about the reach. Overstating significance is a credibility risk; understating it suggests you do not understand what you have done.

Has anything been published on this since you submitted?

Examiners sometimes ask this to check whether someone else has published something that undercuts the novelty claim. Know the recent literature in your area, at least up to submission. If something relevant appeared after you submitted, acknowledge it and explain why your contribution still stands.

Why did you structure your literature review the way you did?

Examiners are testing whether the structure is argued or arbitrary. A thematic structure, a chronological structure, a methods-based structure — each implies a different logic. Know why yours is the right one for your question.

You don't cite [author/text]. Why not?

One of the most common examiner tests. The right answer acknowledges the work, explains why it is outside your scope or why you consciously de-prioritised it, and does not pretend you have not heard of it. If you genuinely missed it, say so directly and assess the impact honestly.

How does your theoretical framework relate to [alternative framework]?

Examiners want to see that you chose your framework for reasons, not convenience. Explain the intellectual case for your framework and the intellectual case against the alternative. Candidates who cannot articulate why they rejected alternatives look like they did not read them.

Where does your thesis sit in relation to [major debate in your field]?

A positioning question. The examiner wants you to locate yourself on the map — which side you are on, which assumptions you share, which you reject, and what your thesis adds to that ongoing conversation.

Is the literature in this field moving fast? How current is your review?

Relevant in fast-moving fields (clinical research, AI, certain social sciences). If your review has a clear search cut-off date, state it. If the field moved after submission, acknowledge the key developments and explain why they do not undermine your argument.

How did you decide what to leave out?

A scope and judgment question. You cannot review everything; the examiner wants evidence that your exclusions were principled. Name the criteria you used — relevance to your research question, methodological approach, time period, or discipline boundary.

Why this methodology? What alternatives did you consider?

The foundational design question. Name at least two alternatives, give a genuine reason for rejecting each (not just 'this suited my data'), and acknowledge what you traded away by going the route you chose. Candidates who say 'I didn't consider alternatives' signal weak methodological grounding.

How did you select your sample, participants, or cases?

Examiners want purposive, theoretical, or random sampling rationale — not 'these were available.' Explain the logic of the selection and what it buys you in terms of answering your research question. If access constrained your sample, say so and explain the implications.

How did you know when you had enough data?

In qualitative work, this often means saturation — and examiners will ask how you judged it. In quantitative work, this means power analysis or a stopping rule. In either case, have a principled answer. 'It felt like enough' is not sufficient.

What steps did you take to ensure rigour?

The answer depends on your paradigm. Quantitative work addresses validity, reliability, and statistical power. Qualitative work addresses trustworthiness: credibility, transferability, dependability, confirmability. If your field has specific conventions around rigour, use that vocabulary — but understand what the terms mean, not just how to spell them.

How did you handle your own position and potential biases?

Relevant in qualitative and interpretive work. Examiners want reflexivity, not a disclaimer. Explain how your position shaped your questions, your access, and your analysis — and what you did to account for that in how you present findings.

How did you analyse your data?

Walk through the actual process, not just the method label. 'Thematic analysis' or 'regression' is a category; the examiner wants to understand what you did step by step, including decisions you made during analysis (recoding, excluding outliers, collapsing themes). Know your process at the level of detail.

If you redid this study, what would you do differently methodologically?

Distinct from the general 'what would you change' question — this is specifically about design. Name a real limitation of your chosen method and explain the alternative. Saying 'a larger sample' without saying why and what it would change misses the point.

Walk me through how you got from your data to this conclusion.

An analytic transparency question. The examiner wants the inferential chain made explicit — not just the conclusion, but the steps. This is especially common when the conclusion seems to jump from the data. Practise narrating the reasoning, not just the finding.

Could you have interpreted this finding differently?

Examiners check whether you considered alternative interpretations or whether you found the one that supported your argument and stopped. Acknowledge the plausible alternatives and explain why your interpretation is better supported by the evidence.

How do you know this is not a spurious result?

In quantitative work, this touches on confounds, multiple comparisons, and replication. In qualitative work, it is a version of the negative case question — did you look for disconfirming evidence? Have an answer that goes beyond reporting a p-value.

What is the relationship between your findings and your theoretical framework?

Did the findings confirm, extend, challenge, or require revision of the framework you started with? Examiners want to see that the theory and the empirics talked to each other during analysis, not just in the introduction and conclusion.

Are your findings generalisable?

Answer proportionately to your method. A large representative survey makes different generalisability claims than a six-case comparative study. Know what kind of generalisation your method supports — statistical, analytic, or theoretical — and do not overclaim or unnecessarily underclaim.

Did you look for disconfirming evidence?

A critical thinking test. In qualitative research this is sometimes called negative case analysis. In any research, examiners want to see that you did not filter for confirmatory evidence. If you did not explicitly look, say so honestly and reflect on what that means.

What are the main limitations of this study?

Prepare three to five, with brief explanations of the implication of each. Limitations of method, sample, scope, and context are all fair game. The examiner is checking whether you can distinguish between 'this is a constraint I accepted knowingly' and 'this is a flaw I did not notice.'

How do these limitations affect your conclusions?

Not a rhetorical question — examiners want a specific answer. For each major limitation, trace the implication: does it mean the conclusion holds only in this context, or that a particular claim needs to be hedged? Acknowledge the ones that matter most to the central argument.

Is there a limitation in your thesis that concerns you most?

This is the version of the limitations question that tests your judgment about which constraints are significant. Name the one that genuinely matters and explain why — don't reach for the least important one to protect yourself. Examiners notice evasion.

If you had another year, what would you add?

A forward-looking version of the limitations question. Name the study, data collection, or analysis that would most strengthen the argument, and why that specific addition — not a generic 'more data.' This also previews your research agenda, which examiners often want to see.

How does [specific limitation you cited] affect the validity of your conclusions?

Examiners will often return to a limitation you mentioned in the thesis and press harder. The answer requires precision: is this a threat to internal validity, external validity, or construct validity? Know which type applies and what it means for your specific claims.

What are the practical implications of your findings?

Be specific about who the audience is and what they would do differently as a result of your findings. Vague answers ('this could help policymakers') are not enough. Name the type of decision, the context, and the direction of change your findings suggest.

What are the theoretical implications?

How does your work change, confirm, or complicate the framework you used or the field's dominant assumptions? If your contribution is primarily empirical, the examiner still wants to know what it means for theory. If it is primarily theoretical, they want to know what empirical predictions follow.

What would you do next if you stayed in this area?

An agenda question. Examiners are partly asking whether you are intellectually alive in this area beyond the thesis. Name a specific follow-on study or question, say why it is the right next step given your findings, and be concrete about method.

Who would benefit from reading this thesis?

Another audience and relevance question. Identify two or three specific groups — researchers in a sub-field, practitioners in a particular context, policymakers working on a defined problem — and give a concrete reason for each. This is not a marketing question; it is a scope question.

How does your work connect to broader debates outside your immediate field?

Examiners in interdisciplinary fields ask this frequently. If your work touches questions that matter beyond your discipline, say so precisely. If it does not, say so and explain the boundary — overclaiming cross-disciplinary relevance is worse than not claiming it.

What is the one thing you most want the committee to take away from this thesis?

A final synthesis question. Your answer here should be your sharpest, most precise statement of the contribution — not a summary of all your chapters, not a list of findings. One sentence, then one paragraph.

What has doing this PhD taught you about how to do research?

A reflective question about practice, not just findings. Examiners sometimes ask this to close an examination on a generous note; sometimes to see whether you have developed genuine methodological judgment. Give a real answer about what you actually learned, including what surprised you.

Is there anything in the thesis you are not confident about?

A candour test. Some candidates panic and say 'no' — which reads as either dishonest or lacking in self-awareness. Others over-disclose and flag things that undermine their main argument. The right answer names a real uncertainty, explains why it did not prevent submission, and shows you understand its scope.

How would you explain your contribution to someone outside your field?

A clarity and communication test. Technical mastery that cannot be translated into plain language looks less secure, not more. Practise a non-specialist explanation that still carries the specificity of the contribution — no jargon, no dumbing down.

Is there a question you hoped we would ask — and we haven't?

An opening for you to foreground something important the examination has not covered. This is not a trick. If there is something in your thesis you are proud of and it has not come up, use this moment. If there is nothing, say so plainly.

Do you have any questions for us?

Often the last thing said. You are not obligated to ask anything, and asking just to fill the silence is awkward. If you have a genuine question about corrections, the outcome process at your institution, or feedback on a specific chapter, ask. Otherwise, a brief and genuine 'no, thank you' is fine.