Sunday, January 9, 2011

What is a "least publishable unit"?

I've recently linked to a Letter in Science arguing that there's nothing wrong with the publication of “least publishable units” (LPUs) and that we needn't worry about a hypothetical paper glut and it's alleged effects on paper quality, provided a rigurous peer review system exists (See Quotes from the science world). This was published as a response to this letter

Dave Bridges posted the following comment on my entry:

(...)to me the question boils down to what the least publishable unit is. Can you publish a single well controlled experiment. Or does it have to be in the context of a story?

So, I wanted to get your impressions on this matter. What do you think constitutes a LPU? How do you feel about these sort of articles, particularly in the context of the advancement of science?

Be sure to check the comments on my last post  and the two related Letters in Science (see here and here).There are pros and cons, obviously, so I wanted to know what fellow scientists think about this interesting subject, which has been discussed at length before, but for which new readers can have interesting insights.

Comment away! Also, follow me on Twitter, as fantastic discussions usually take place through it. 


UPDATE: There are some comments over at Friendfeed.



Chris Dieni said...

Ugh... muddy water.

I could go either way on this one. But yes, as my scientific cousin Dave says, the trick here is to define what a LPU is.

Something that my Ph.D. supervisor once told me is that the more you include in a publication, the more there is to explain, the more there is that can be attacked by reviewers and then, subsequently, by readers and colleagues. The bigger the dam, the more likely that a small hole appears somewhere in that dam and springs a leak.

I liken this to an acronym I once learned from an army officer, KISS: Keep It Simple and Stupid.

A single well-controlled experiment, or a very small collection of well-controlled experiments is, in my mind, perfectly acceptable as a publication. I think that's the whole reason why we have journals that publish "letters" or "rapid communications" type papers. In fact, there are a lot of odds and ends of data I have stockpiled that I'd love to publish as small stuff; studied where I don't need to add layers upon layers of experiments, and in turn receive comments back from reviewers asking me to pack on yet more experiments to justify the results!

On the other hand, I also like longer publications, where I've got 6-7 figures worth of data, maybe a table or two, and a discussion rich with the synthesis of current and previous data, speculation, and theory. In fact, all of my publications to date have been of that type.

To put this in context and explain where I'm coming from: to be perfectly candid, I don't see myself as a "big gun" scientist as the many who are out there today. If ever I'm fortunate enough to be a PI and run a lab, I wouldn't be surprised if I never see a postdoc come through my doors and never get what many term to be a "high impact" publication. I love to focus on undergraduate education, though having grad students is definitely a plus and something I'd love; also, before I ever gave my students more ambitious projects to work on, I would most definitely start them off with something surefire to produce results, build up confidence, and start them off on a path that instils a strong interest and passion for science. Would those types of projects then constitute LPU type papers? I guess that's the core of what we're trying to answer.

Coming from my most recent experiences, to add to this: I also feel that the "old school" way of disseminating scientific information should no longer apply. I blogged about a publication on G6PDH here on Alejandro's blog and a journalist friend of mine also wrote a story about it geared to a more general audience. So, is the LPU okay, provided that, after the publication comes out, we follow it up by talking about in social media, and try to explain the value of the publication there?

All food for thought...

Psi Wavefunction said...

Muddy water indeed. Apparently some accuse us of indulging in LPUs, but as our PI explains, there needs to be a certain accumulation of 'smaller' papers upon which 'bigger' papers can be later built. Otherwise, what you'd get is constant recycling of old [popular/established] data as most new stuff is guaranteed to seem unimportant at the time. Furthermore, you never know when an LPU can suddenly become a keystone paper in some later project. For example, with the eukaryotic evolution stuff, many of the phyla are quite literally waiting for LPUs to pile up before someone can write up a comprehensive review of their evolutionary history. Otherwise, there's just too many taxonomic holes. Sure, you may not care about Trigonomonas and Octamita, but you can't say anything particularly thorough about diplomonad evolution without them, nor can you properly treat eukaryotic evolution without the lesser diplomonad reviews, for example.

Unfortunately (or maybe fortunately), no one's gonna wait 30 years for you to finish your Grand Project of Awesome. Furthermore, it's kinda nice for others to gain something from your Grand Project of Awesome in small increments instead of having to wait. I guess piles of LPUs can get wordy, but then again, most papers aren't read in their entirety. In fact, depending on how deeply I need to know the topic, I may only skim the abstract + discussion if it's something tangential. You don't have to read all the wordiness.

Just my 2 cents. I tend to lean on the "publish everything, reader must filter themselves" side, but how much is an undergrad's opinion worth here...? >_>

As for defining LPUs...let's define species, cultures and words first, for starters! ;p

Chris Dieni said...

Psi Wavefunction: an undergrad's opinion is just as valid as that of a grad student, a postdoc, a research associate, a PI, and whatever else you'd care to throw into the spectrum. And anyone who tells you otherwise is full of hot air!

Undergraduates represent the future of science as much as anyone else- maybe even more. And, perhaps very importantly, they're a lot less likely to be fully indoctrinated into the system, and thus, may see things more clearly and objectively.

Keep offering your opinion anywhere and everywhere, as you see fit!

Michael Scott Long said...

I don't care as much about a paper's length as I do the thoroughness of the investigation itself. A short paper that is carefully considered makes a much more positive impression on me (and is more likely to be fully honest and truthful) than a long and half-ass paper.

el astudillo said...

I read somewhere an interesting concept. Advance of science should not be only "positive" results. Specially considering that a great part of science funding comes from public sources (taxes, government investment), we should be more considered about the waste of money, so, in that sense, it is a good idea to give room to "negative" results. You can save a lot of money if you can get an idea in advance about the possibility of success of some experiment. For example, if your lab tried for a long time to demonstrate a correlation between the phosphorylation of a specific protein and a phenotype without sucesss, that could be amenable to be published. The journal "Research Notes" in BioMedCentral has this scope, and I think is very valuable at some degree. But it has to be submitted to peer-review and I doubt that researchers will be willing to review "negative" results.
On the other hand... I hate papers with 10 figures. The purpose of a publication is to describe reproducible research, not to write a book.