Prior to submitting, you and your supervisors will nominate an external and an internal examiner. Your PhD outcome will depend on their review of your thesis and your performance at the viva. This is an important decision, do be a part of it! You should make sure you know their work. They have to be experienced and clearly independent. You’ll want to find someone who is sympathetic to your model of a PhD (your supervisor could have a delicate discussion with them about this – without lobbying of course!). Someone with a reputation for being a tough but reasonable examiner would be ideal, giving credibility whilst still being fair.
Examiners have normally pretty much made up their mind about the decision prior to the viva. However, you can sway them in a positive direction by a robust defense of your work. You need to strike a balance between justifying why you did what you did and seeming irresponsive to their advice.
Commonly, you will be asked to start your viva by an overview of what you found. Prepare a quick impressive sounding synopsis really selling it (For example: “What have I discovered?”). Questions will then focus on;
- your knowledge of the area.
- your theoretical conception.
- the methods you’ve used, including analysis.
- how the research may be continued.
Often, examiners are not trying to catch you out or have a problem, rather just want to check your understanding, so don’t stress too much!
You can pre-empt (d) by having a strong section in the discussion part of your thesis. This also reassures them that you’ve made the transition from doctoral to “independent” researcher. Remember, other than the (rare) unconditional pass, examiners can recommend minor corrections, major corrections, or other worse outcomes. If something can’t be justified, convincing them that you are ready and able to make the corrections easily may make it minor rather than major corrections (or worse!). Non-professional/disagreeable responses can also go against you (For example: I don’t care about statistics).
Try and have a practice viva with someone. Most vivas are a lot less scary than they seem in advance.