Lancaster University's pioneering scheme to ensure that PhD vivas are not open to abuse has proved a success despite initially being condemned by academics as unnecessary and insulting.
Concerns have grown in recent years about the difficulty of ascertaining the truth if a candidate claims to have been treated unfairly or aggressively in a viva, which is traditionally held behind closed doors.
Lancaster has begun to give candidates a choice of having their vivas monitored by an independent chair or by an audio recording.
The pilot study has been assessed by Carolyn Jackson, lecturer in educational research at Lancaster, and Penny Tinkler, senior lecturer in sociology at Manchester University.
Dr Jackson said the two approaches had different purposes. "The independent chair is there almost as a trouble-shooter during the viva, while the tape recorder is principally a safety net in terms of an appeal."
She and Dr Tinkler will reveal their findings this week at a meeting of the postgraduate issues network of the Society for Research into Higher Education.
Despite academics' initial disquiet about an implied slur on their professionalism, neither examiners nor candidates found any problems with having an independent chair.
A quarter who had recorded vivas reported problems, but these were technical. "Lesson learnt - sort out technical matters before introducing audio recording," Dr Tinkler said.
Dr Jackson said some examiners had warned that recording proceedings would make candidates uneasy. "But candidates are uneasy anyway. If there's no tape recorder, it's not going to make them relaxed."
Just over half those taking part in recorded vivas said the measure was not useful, but Dr Tinkler said this generally reflected an unproblematic viva rather than an objection to the procedure.
Half those involved in chaired vivas found them useful, while a third did not, again largely because no difficulties had arisen.
One candidate said: "He was friendly and introduced everyone, but he didn't really seem to serve any purpose."
But one examiner said: "Although the viva examinations were straightforward, one can never tell that. It is something of an insurance to know procedures are in place should students question procedures."