The Life Scientists’ Guide to Examining Your First Dissertation Defense

The Life Scientists’ Guide to Examining Your First Dissertation Defense
2 years ago

The Life Scientists’ Guide to Examining Your First Dissertation Defense

After years of hard work and dedicated research, you’ve finally reached senior academic status as a scientist, and it won’t be long before you’re asked to sit on your first dissertation defense panel. You’ll no doubt remember your own defense (or viva) well and will want to make sure things go as smoothly as possible for both yourself and the candidate. 

It’s a big responsibility, so to help ease the pressure a little, we’ve gathered some top tips from seasoned examiners to ensure your first experience on a defense panel is a positive one.


Examining roles

The structure of a defense panel varies in different countries. In the UK, a dissertation defense is known as a PhD viva and will generally be conducted by a two-person panel consisting of an internal and an external examiner. In the USA, a dissertation defense committee will be made up of 4 or more examiners. Regardless of location, your first experience as an examiner will almost certainly be in an internal role, and you may be supported by an independent chair or observer to provide extra guidance where needed.


External examiners

An external examiner will be a senior academic from an outside institution who will have considerable experience in the examining process. They will be expected to lead the conversation and will ask the majority of the questions, digging into the finer details and asking more in-depth, probing questions.


Internal examiners

An internal examiner will be from the same institution as the candidate. They may ask more data-related questions, checking stats and figures with the candidate, rather than the heavier, more left-field questions that an external examiner might pose.

When accepting a role as an internal examiner it’s very possible that the candidate will be somebody who is already known to you, or someone you have worked with previously. If they are very well known to you, for example someone you have co-published with, then this may create a conflict of interest and it would be advised that you decline the role on that particular occasion.


Dissertation committee

A US dissertation committee will have a minimum of four persons, consisting of a chair, core members, institutional representatives and specific department advisors. In the UK, a PhD viva is a closed meeting, however in the US and European universities public examinations are quite common and there can be very strict protocols.


Examining qualities

What makes a good examiner? You’ll need to be a confident communicator who is able to listen well and engage with both the candidate and the other examiner(s) constructively. A good understanding of the research topic is important, and thorough preparation is vital in order to make the candidate feel comfortable and give them the best chance of success. Attention to detail is important, but the ability to see the “bigger picture” is essential.

Stuart Maudsley is an experienced examiner in his role as Vice-Chair of the Department of Biomedical Research at the University of Antwerp. He told us: “One of the most important qualities needed to be a good examiner is the ability to understand how best to work with the student to make sure they represent themselves and their work in the best manner possible. It is their day to shine and demonstrate their qualities, so as an examiner try to be a supporter of this. Be patient, respectful, responsive and above all, well-intentioned.”


Preparing for the examination

There are a number of things you will need to do in advance of the examination, with the first and most important being to read the candidate’s thesis thoroughly. Familiarise yourself with the research topic and ensure that you have a good understanding of the work before you begin to prepare questions.

Matthew Lloyd, senior lecturer at the University of Bath, shared his regular preparation routine: “I like to read the thesis a long way ahead of the viva, ideally two or three weeks in advance. If possible read the entire thesis in one sitting. I take notes as I go along, using pen and paper, highlighting a) things I want to discuss in the viva and b) things that need to go into the minor corrections. I will then write these up into Word documents which I will share with the other examiner close to the viva. I will then re-read key bits of the thesis either the night before the viva or on the journey to the viva, depending on how much time I will have.”


Check the rules and regulations

If examining for a UK university you will be required to prepare a pre-viva report and produce a clear and detailed list of suggestions for the candidate, which will provide guidance during the revision of the thesis. It’s also important to read the relevant rules and exam regulations thoroughly, and ensure you are aware of the format of the examination. Be sure to raise any questions or flag up any issues with the institute in advance of the defense.


Clarify your roles

You will also need to arrange a meeting, or a telephone call, with the other examiner(s) to clarify your exact roles and to coordinate who is going to be asking what. After this discussion you should be in a position to finalise the list of questions that you intend to ask.


Practical checklist

The average duration of a viva is between 2.5 and 4 hours, but they can be longer. Be sure to consider the comfort of both yourself and the candidate by working through this practical checklist:

  • Room temperature - When preparing the examination room, check the room temperature and make sure you know how to adjust this if necessary. Check to see if windows can easily be opened if fresh air is required at any point.
  • Signage - Bring a printed ‘do not disturb’ or ‘examination in progress’ sign to attach to the door(s) before the examination begins. This is something that can sometimes be overlooked.
  • Refreshments - The institution should provide drinking water, and possibly teas/coffees, but check in advance in case you need to bring your own refreshments. Also, be sure to check that the candidate has drinking water with them before beginning the examination.
  • Accessibility - The institution should inform you beforehand of any accessibility issues, but be sure to check with the candidate as to whether they have any specific requirements, eg. wheelchair access.
  • Timings - Keep a check on the time throughout the examination and be sure to allow for toilet and/or cigarette breaks when necessary.

Matthew Wilkinson, KTP Associate at the University of Bristol told us of his experience during his recent PhD viva. He said: “I would have appreciated more of a break during my viva! It lasted for over five hours and I was only offered one 2-minute water break!”

Stuart Maudsley adds: “Try to prevent the whole process taking more than 3 hours. Anything longer than that turns into a process where most students (and also examiners) may not retain their focus for this period of time.”


Acknowledge the positives

Before launching into your prepared list of questions, there are some additional things you can do to put the candidate at ease from the start. Take a moment to explain how the defense will be conducted and the format it will take. Many examiners will give the candidate an opportunity to briefly introduce themselves and their research before beginning the formal questioning.

Matthew Lloyd told us: “I often ask the candidate to give me a 5-minute synopsis of their project highlighting the most interesting and important results. This gets the candidate talking about something they know well and will help settle their nerves.”

Elek Molnar, Professor of Neuroscience at the University of Bristol, has some other great suggestions for keeping the candidate relaxed: “It is always a good idea to explain to the candidate how the viva will be conducted and what type of questions they can expect. It also helps if the examiners acknowledge the positive aspects of the thesis first and emphasise that the questions may appear to focus predominantly on weaknesses, but there are also several strengths and that these did not go unnoticed. Normally I mention to candidates that they are the real experts of their research area, and I am just here to learn from them. Asking candidates about future career plans can also help them focus on their achievements and the amazing opportunities they’ve created through their hard work.”


Adding a personal touch

Reminding the candidate that you’ve been in their shoes can also help to ease their fears. You know exactly how it feels to be in their position, so it can be a real comfort for them to hear this from you.

Stuart Maudsley says: “Most examiners themselves will likely be ex-viva/presentation veterans and therefore will remember what it was like to be in that seat. Put yourself in their place and try to be the ideal examiner that you would have wanted for your own presentation. Making sure that the student knows of your direct experience will hopefully create an emotional bridge between you on the day that will allow them to appreciate that your questions are coming from a position of support and good intentions.”

Matthew Wilkinson told us how some thoughtful words from his examiners put him at ease: “The first thing that the internal examiner said was that they had enjoyed reading my thesis, and told me that the viva was a rare opportunity for me to discuss my work at length with two people who really care about it.”


A conversation, not an interrogation

Although you are conducting a formal interview, it doesn’t have to be an interrogation! Many examiners prefer to think of the defense discussion as an interesting conversation on a topic that all parties are interested and enthusiastic about. A more relaxed style will help the candidate to open up more and express themselves more concisely.

Stuart Maudsley says: “As an examiner, try not to be too inquisitional and try to couch questions in a more conversational manner, as if you were having a chat with an old colleague. Science should be collegial, not confrontational… we should all be working together to improve the human condition!” 

Matthew Lloyd agrees: “The role of the examiner is to help the candidate produce the best possible final thesis. Assuming there are no major issues with the thesis, treat the discussion as an interesting conversation between the candidate and examiners about the research that has been done. Even if there are major issues, try to maintain the “interesting conversation” insofar as possible.”


Be prepared to change direction

Although you may be entering the process with a set of prepared questions, be aware that you may need to think on your feet and ask something different if the conversation takes a different turn. If the candidate is clearly struggling, it can help to rephrase a question in order to keep the conversation flowing.

Matthew Lloyd advises: “Ask open questions whenever possible on a range of subjects. I usually try to spread my questions around the introduction, the methods and the results and discussion. Many candidates are excellent on their specific research but “fall down” a little when asked something slightly off-topic. Be prepared to restate your question in different words if needed, or break the question down into smaller steps if they are struggling with your first question. I often ask questions about how particular techniques work as this is a good way of testing if the candidate has understood what they are doing.”


Virtual considerations

In 2020, the majority of dissertation defenses switched to virtual platforms which brought a new set of considerations for both candidates and examiners alike. Defending a thesis in-person can be daunting enough but the additional pressures of a video call can add to the stress for all involved. For more on this topic from a candidate’s point of view, take a look at this guest article by Dr Harry Potter on the Hello Bio blog. 

Thankfully, in-person examinations are now becoming the norm again, but there may still be occasions when you are asked to take part in an online defense. If so, here are a few things to consider:

  • Accessibility - Check the video conferencing platform beforehand to make sure it is working properly and that all parties can access it without any issues.
  • Connectivity - Have a back-up plan in case the platform fails and decide what to do in the case of internet connectivity issues.
  • Space - Ensure that the candidate and each examiner have a private, separate room from which to participate and in which they will not be disturbed.
  • Regulations - At the start of the video call, all parties will need to be able to show that they are on their own and that only approved materials are present.


Dealing with difficult moments

A dissertation defense is the culmination of years of hard work and sacrifice, and can often be an intense and emotional experience for the candidate. It’s important to be aware that emotions can boil over if the candidate finds themself struggling with questions, or feeling as though the defense is not going well. As an examiner you will need to deal with any heated moments carefully and be sure not to exacerbate the situation.


Keeping your cool

Matthew Lloyd suggests a calm line of questioning where possible: “In the viva, be human! This is the culmination of 3 or 4 years of work for the candidate and they will be nervous at the start. Avoid a confrontational style of asking questions as much as possible, especially if the candidate seems particularly nervous or is being examined in a second language.” 

Should you find yourself in the position of having to fail a candidate, try to do so tactfully with any criticism being as constructive as possible. Deliver feedback as carefully as possible to ensure the candidate remains motivated to persevere despite their current failings.

Elek Molnar shared his experience of a difficult examination and how he dealt with it: “On one occasion I had to make the difficult decision as External Examiner to fail a PhD candidate due to poor understanding of the research topic. Following a long discussion of a range of topics it was clear to all of us that the candidate focused almost entirely on technical aspects of the work and lacked the required understanding of the theoretical aspects of the project and the relevant literature. Whilst the candidate fully agreed with this decision and remained positive, I felt really bad about the whole situation, and I apportioned some of the blame to the supervisor who had approved the submission of the thesis. After the viva the candidate sent me a very nice letter to thank me that I’d helped him to recognise his weaknesses, which motivated him to improve his knowledge. The PhD was eventually awarded based on a much improved dissertation.”

If there are any concerns in advance of the examination that serious issues may arise, it’s important to discuss them openly and honestly to make things as transparent as possible for all concerned.

Stuart Maudsley told us: “I’ve been lucky enough not to have any heated exchanges but I have had experiences where agendas have existed before the examination where seemingly decisions had already been made. To deal with this it is important for the examiner(s) to meet candidly beforehand to contend with any hidden actions that may take place during the exam. For the student to feel properly treated, it is vital that the examination team are all honest with each other before the examination.”

Matthew Lloyd adds: “If it is likely to be a “difficult viva” it is important to discuss your concerns with the other examiner (but not with the supervisor(s) or the candidate). Also it’s important that a difficult viva is properly documented, and this can be done by the internal examiner or faculty appointed note-taker.”


An honour and a privilege

Being part of a dissertation defense panel is an important role which should be seen as a great responsibility and privilege. The examination is a milestone event in the candidate’s life and it needs to be treated with respect and sympathy. Working hard for a PhD over 3-4 years and dealing with potential setbacks can be an intense experience and the defense marks the completion of this period of someone’s life. It's a hugely rewarding experience to be part of, especially when the candidate is successful! 

Stuart Maudsley says: “If you’ve done your homework and prepared well, both you and the student should (hopefully) enjoy the experience! It’s always a pleasure to be able to help a candidate present themselves in the best way possible and to help them in their career development. I always hope that the student retains a positive memory of their dissertation defense – it really should be a positive experience for all involved.” 

And finally… at the end of the viva, don’t forget to congratulate the candidate! If they have produced a particularly good thesis or defense then say so! They have worked hard and deserve their moment of glory.


What are your experiences of sitting on a PhD viva / dissertation defense panel? What advice would you give to someone preparing for their first time as an examiner?

Send us a message on Twitter @hello_bio or email We’d love to hear from you!


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