PhD Thesis / Paper Results Conflict



So I have a situation that I'm sure must have existed for many before, but haven't found anything out about it. I submitted my PhD thesis 3 months ago now, and should have my viva before the end of this calendar year. Right after my thesis submission, we sent off a paper based on the same results, they liked it but had a couple of things they wanted us to do and add on review, as in new experiments.

Basically, one of these threw up a totally unexpected result that essentially destroys a fundamental tenet of the thesis! (As in, the thesis data is otherwise all perfectly valid, it just doesn't mean what we thought and is basically not very relevant to the biological system we studied any more). Pretty much, we believed we were adding a sugar at a defined site on an enzyme to mimic a biological system, had 3 chapters discussing study of this, but actually it was at a different, erm, bit of a disaster! Should add, we did have some evidence previously to support our initial conclusions, it was just disproven by this extra experiment that we didn't do before because, well, we had no reason not to distrust the earlier evidence.

I don't care too much about the paper, I have no interest in going into academia / post-doc. But I'm worried about the PhD. I don't want to have to fail after 4.5 years! What's, in your opinion, the best course of action? Defend my thesis results in the viva, even though I know they aren't actually right? (This is my intuition - at the time, I had no reason to doubt them, it's not an actual error and science gets disproved all the time, just usually not this quickly I guess). Or somehow re-write it? But that would be a major, major re-write with many new experiments needed - I have a job, I'm not really willing or able to do that.

Thoughts welcome!


Composing a theory is a troublesome undertaking for some understudies on the grounds that amassing a very long time of research in a solitary paper is some work. Believe me, composing a theory isn't as simple as some of you may think. In any case, it doesn't mean you can't accomplish it, once you decide that you must do it, you'll do it.
I can provide better tips.


Hi mkb91,

Yes, this is a pretty unusual situation. I guess it does happen a lot, but usually on a much smaller scale e.g. I had a few results in my thesis that I realized were wrong as I was finishing up the thesis, but it would have been quite a lot of work to change them and didn't affect the overall outcome of the results. I just omitted these from the paper that came later. I discussed this with my supervisor and he said this was the easiest thing to do.

In your case, the paper came first. What does your supervisor think?

I think leave the thesis as it is and explain what has happened in the viva, then add a paragraph addendum of explanation and the paper at the end of the thesis with the actual result. You've already submitted the thesis in good faith, so I don't see how you can change it now. I don't think the examiners will ask you to either - it was correct to the best of your knowledge at the time of submission.



Thanks for the reply. The addendum idea seems a good one. As said, it wasn't like something glaring I omitted - I had evidence from other means that the modificaton site was where we expected, so went on this - we had no reason to disbelieve this (either in theory or practice) until this extra expt threw up a storm!

My supervisor I think is along the same lines, kind of "what I submitted was correct to the best of our knowledge when I submitted it, and it wasn't like that knowledge was too limited".

To be honest, this has all become a bit less important thanks to a job offer that is not conditional on my PhD - so, worst case, I'll still have that!


Congrats, on the job mkb91! This will all be fine, and will seem like a storm in a teacup in a few weeks I'm sure!