How likely is it that an PhD examiner will find something I've missed? And if they do, how much of a problem is it?

Question

I'm coming up to the end of my PhD. My work is industry funded, so although I've presented my work, and written technical reports and patents*, I'm probably not as experienced in 'scientific writing' as perhaps I should be and my literature reviews have tended towards application-based, rather than pure science.

I've made what could be a big discovery, but I can't shake the feeling that the general case must have been observed somewhere before — maybe not in my field, and not with the exact materials I work with, but it seems too obvious for nobody to seen or thought of it.

I've described it in my thesis and said it's new for my materials etc but my supervisor says that I'm underselling it and it could be a really big deal. We've been referring to it with one specific name — literature searches on that bring up nothing similar. I've tried what I think are synonyms and can't find anything. I've written that it's a novel pathway for my material, and again I've been told to make it a bigger deal and say it's novel in the general case.

I'm still worried. What if my examiners decide to do their own lit. search, and hit on a search term I just haven't thought of, and there are actually lots of examples? I feel like I've searched lots of things, but perhaps somebody with a different background will think of another search term, or worse, just know an example. I've tried searching adjacent fields it might be related to (chemistry/geology/construction/material type) but I know that wording can be different in different fields as well.

If I'm right and it is brand new, then it's really exciting. If I've missed it though, and the examiners find it, realistically what will happen? I'll have to correct obviously, but I'm worried that they'll accuse me of "reverse plagiarism" and not looking hard enough so I can make it sound more impressive.

*A patent based on this has gone through, and I've checked what the examiner has written to see if he found anything similar (he didn't). However, the patent focussed purely on my particular system and it wasn't written as being a new general pathway, he might not have looked for that.

Answer 1

Here are some observations I've gathered from reading your question (with the disclaimer that I don't know you and am taking your description at face value).

• You have done a PhD in a topic and know that area extremely well.
• You have done a thorough literature search with different search parameters and have not found something equivalent to your work.
• Your advisor thinks your work is exciting and that you are underselling it. So you are not the only person who thinks your work is novel.

Given all this, I think it is extremely unlikely that your exact work exists elsewhere. Maybe there is overlap with some work you don't know. But even in the absolute worst case scenario that this hypothetical overlap exists and is significant, people in your field are apparently not aware of it. So even in the worst case, you are still making a contribution by connecting those results to your field.

Additionally, keep in mind that no one has thought more about your thesis than you. Your examiners may ask tough questions and realize connections to other work you didn't know. But they are extremely unlikely to find an obscure connection with such a major overlap in their literature search that you missed. Even if it exists, this connection is much more likely to be made by the person who actually did that work, than a busy professor with their own interests getting up to speed on your topic. And in the even-beyond-worst-case scenario that your work significantly overlaps with some obscure paper that one of your examiner happens to know about, I really doubt that they would accuse you of wrongdoing; if they thought you were dishonest I doubt they would agree to be on your committee, and to accuse you of dishonesty would also by implication be accusing your advisor. But more to the point, it wouldn't lead anywhere productive. Based on the professors I know, I think it is much more likely that they will bring it up to try to help you, and you can show how your work is complementary or builds on it or how you can relate it to your field. However, to reiterate, I think this scenario is unbelievably unlikely.

I think it is much more likely that you actually have made an advance. Bizarrely, sometimes this can actually be more stressful than realizing your work did not make as much of an impact as you originally hoped. Presumably there is now a research program that can be built on this advance, and it will take a lot of energy and work you can and should now spend in developing the ideas and pushing it forward. Apologies for the armchair psychology, but sometimes we get wrapped up in "worst case thinking" as an avoidance mechanism for the most likely case. Writing your thesis is a stressful time. Take some breaks and occasionally let yourself be happy about what you accomplished.

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It's maybe worth adding a sentence about what I mean by "probability" here. When I say it is "unlikely," I mean in the sense that a reasonable person could assign a small degree of belief to the possibility that there is an obscure overlapping work and act accordingly without being irresponsible. Reasonable people would not rake you over the coals with criticism if it turns out your nightmare scenario turns out to pass, because you aren't omniscient and sometimes rare things happen. If it does happen, it happens, and you'll deal with it. But, being overly concerned about rare events, can mean that you are underprepared for more likely ones.

Answer 2

Even experienced researchers can wrongly believe to have discovered something new when a similar observation had been reported before. The consecrated phrase to tone down a priority claim is "to the best of our knowledge". As far as I understand, your discovery is indeed to the best of your knowledge entirely new. You can write it, and in case a reviewer proves you wrong, what is expected is that you'll be even more interested than disappointed!

Answer 3

Just submit to the reviewers and see what happens

It's always possible that you and your supervisor have missed something, and really, we can't offer any helpful analysis of how likely this is. It happens sometimes in academic work. I've had it happen to me a couple of times due to literature searches that did not search the correct keywords (see this related answer), but fortunately not for my PhD dissertation. You are in a situation where neither you nor your supervisory panel are aware of previous publication of this work, so the best thing to do is to submit to the reviewers and see what happens. If it turns out that there is some existing work you've missed, you can revise accordingly.

I also note your statement that your supervisor thinks you are "underselling" your work. Personally, I'm a big fan of work that is understated, so if you have a big discovery and present it in an understated manner, that sounds pretty great to me. Of course, you should consider your supervisor's view here, but in my view it is much better to understate the importance of your own work than to overstate it. Referees are experts in the field so they will be able to judge the merits of the work without being beaten over the head with how important it is.

Answer 4

Being a new idea isn't a binary. One thing that always strikes me when trying to find discovery dates is that discovery is a fuzzy process.

Normally the best things are rediscovered many times over. Neural networks are a good example (see Pattern Recognition and Machine Learning, Information Science and Statistics by Bishop). Yes, maybe someone else has done something similarish, with a different name, in a different field. But if you have put it into a better format, and seen its use as the solution to a problem that the other person missed, that is a groundbreaking contribution.

So, yes, do make it clear that you have done a literature search and not found it elsewhere. If possible, name the next closest thing you know of. At worst, your reviewer knows of a closer example, and you have to make a correction. They won't fail you for that, it's just a correction.

Also, this may be less obvious and surprising than you are imaging. We tend to forget how specialised our field is, and how few people are involved. It's easy to forget that the central problems and advances in our world are not even on the radar of someone in the proverbial "next room". This normally becomes more apparent at conferences. At a conference, I'd normally want to spend at least half my talk explaining the state of the art in my field, otherwise there is no clear need for my work.

Answer 5

How likely is it that a reviewer will point out relevant research you missed? Unlikely. They have limited time and are unlikely to know the details like you do. It's more likely that they'll point out something that they think is related but is not actually related in my experience.

How likely is it that you missed relevant research? 90% probability or higher. The amount of literature out there is vast and finding synonyms isn't easy. I tried hard to do a comprehensive search during my PhD but I still missed relevant documents. Most likely the relevant research won't be the same exact thing, but maybe it will be.

If you have missed something, I wouldn't worry too much about it. Most likely it won't be exactly the same. Highlight the differences and move on.

You can probably call the patent examiner on the phone to ask about what they searched and what they did not search if you want to be certain. Your patent attorney may want you to not speak to the examiner at all, unfortunately. There are also various search logs you can look at. These vary from a list of the "field of search" which is just patent classifications searched (this is listed on issued US patents) to a timestamped log of search queries run and a narrative search notes document. You can check websites like Global Dossier for your patent application to find these logs.

Answer 6

The point of a Ph.D. defense is to show that you know a specific topic to an expert level and can contribute to creating new knowledge in the area. There is no expectation that your work is flawless and spectacular. No sane examiner will kill your work at the defense. If there are serious flaws you will know in advance.

Furthermore, you can defend only what you have done. If your opponent points out relevant work that you have missed, use your literature search methodology as a defense. Ask your opponent to explain how the missed work is relevant to your work. Listen and point out your specific contribution.

People come up with similar ideas independently all the time. You will be accused only if the similarities are on a detail level, e.g. word order in the description and such.

It is good to have a mock defense with some tough opponents. Start with some soft and likely questions, end with them hammering you until you cry. Observe and learn how to respond to tough and provocative questions. Write down strategies for how to exit from a corner.

e.g.

Opponent: This work is exactly what X did 5 years ago. How did you miss it?

You: Thanks for pointing this out. My work was done specifically for company Y taking their specific needs and context into account. We further implemented the results into zzz. A patent was submitted as a result.

Answer 7

I am making some assumptions here, but even if the phenomenon turns out to be known and previously studied, you could rework your thesis to describe what novelty it brings to your field.

Answer 8

It's vital to distinguish between work adequate for getting a patent and that done towards a PhD.

Whether you get a patent or not is not a concern for your external examiner: he/she is concerned with the (knowable) independence, originality, substantiality and worthiness for publication in peer-reviewed journals of your final thesis.

To you and your supervisor this is at least a novel path for the materials you've applied it to. Your supervisor thinks it novel for a range of materials too. But you are not so sure and want to remain cautious for the time being. I think that this is wise as external examiners dislike immodesty even more than opaque writing and you don't need trouble at the final hurdle.

On the general question of your thinking that someone working in your field must have come across this before, I know how you feel. What you did might have seemed rational or a common sense thing for someone working in this field to do. Hence your doubts.

To allay your doubts, try to reduce the gist of your innovation to its pure science (e.g. chemistry/physics) essentials. Using the relevant terminology for the phenomena involved, do some more literature searches. Not just papers, but texts, theses, conference poster papers and other media too. It might be worth discussing the value of the innovation with a senior scientist in a relevant government laboratory - but only do so after getting approval from your supervisor as not every government scientist puts country over pocket-money, sadly.

You have had a good outcome to your work. Appreciate and enjoy it. Maybe keep a memento of these successful experiments as a gift to your father and mother.

Answer 9

I wish to point out that, over the history of science, there are any number of stories where two people discovered the same thing at roughly tomorrow. A famous example is Alexander Graham Bell and Elisha Gray invention of the telephone. That fight went to the US Supreme court. See also the Leibniz-Newton calculus controversy.

So if you find that somebody did discover something along the same lines as what you have found, you will be in distinguished company.

I have every confidence you are beginning a long and productive career.

Answer 10

As others have stated, you are almost certainly the worlds foremost expert on the exact thing you have done. However, if you are working in a system where you will have two examiners who will devote substainal amounts of time to studying your thesis in preparation for a formal exam (e.g. the UK), then they will almost certainly find some things that you have missed at some point. Almost all theses require some level of corrections after the viva - this is expected, and is not a problem.

However, it is unlikely they will tell you your entire concept is no good. In the unlikely situation where someone has published something very similar that you haven't found, the most likely outcome is that the examienrs will make you write a section discussing this existing work and how it is similar and how different from your own. It will not prevent you getting a PhD, and since you already have the patent, when what other negative outcome could it have?