Scientific Papers Are Getting Less Readable

By Neuroskeptic | September 16, 2017 2:37 pm

“The readability of scientific texts is decreasing over time”, according to a new paper just out. Swedish researchers Pontus Plaven-Sigray and colleagues say that scientists today use longer and more complex words than those of the past, making their writing harder to read. But what does it mean?

Here’s the key result. This image shows text readability metrics from 709,577 abstracts, drawn from 123 biomedical journals, published in English between 1881 and 2015.

There’s been a clear decrease in Flesch Reading Ease scores, along with increases in New Dale-Chall difficulty scores, both of which indicate declines in readability. These metrics are often used to estimate the ‘reading level’ of a text, and Plaven-Sigray et al. say that “more than a fifth of scientific abstracts now have a readability considered beyond college graduate level English.”

What’s driving the change? These readability metrics are based on a combination of the average sentence length and the average word length (Flesch) or word ‘commonness’ (Dale-Chall). Plaven-Sigray et al. found that the decreasing readability of abstracts was mostly due to changes in word use, although sentence length has been increasing slightly since 1960.

In particular, Plaven-Sigray et al. point to increases in the use of what they call “general scientific jargon” or “science-ese”, which they define as “vocabulary which is almost exclusively used by scientists and less readable in general.”

‘Science-ese’, they say, includes words like “moreover”, “underlying”, “robust”, and “suggesting”. While not scientific terms per se, these are rarely used outside scholarly discourse today. Plaven-Sigray et al. show that use of these words has increased over time, and have contributed to the decrease in readability.

The full list of ‘general scientific jargon’ can be found in a supplementary file here.

Overall, the authors conclude that:

We have shown a steady decrease of readability over time in the scientific literature… Lower readability implies less accessibility, particularly for non-specialists, such as journalists, policy-makers and the wider public… decreasing readability cannot be a positive development for efforts to accurately communicate science to non-specialists.

On the other hand, non-specialists in the past would have struggled to even find a copy of a biomedical abstract, so I’m not sure they would have been able to benefit from its readability.

Overall, I’m not surprised by these results. In fact, they match nicely with my own analysis of word use in abstracts, in which I noted that there’s been a shift in the words scientists use to describe their findings. While 100 years ago, terms like “notes” and “observations” were preferred, there has been a gradual shift towards more formal, specialized terms like “data” and “results”. I speculated about what this means:

The rise of “data” seems to reflect a reversal in the relationship between science and the rest of the world. My impression is that “data” is being used more and more widely in normal discourse but this is a borrowing, so to speak, from science, whereas previously, science was borrowing from everyday life.

Finally, Plaven-Sigray et al. use the acknowledgments section of their paper to say that “This article has a FRE score of 49. The abstract has a FRE score of 40.” This post, meanwhile, has a FRE of 55.

CATEGORIZED UNDER: history, papers, science, select, Top Posts
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  • Uncle Al


    Even including cheaters, paper titles versus jargon assemblages are indistinguishable, 57% to 43% over 1,393,010 instances.


    • Stuart McKelvie

      Perhaps everyone should read Helen Sword’s “The Writer’s Diet: A Guide to Fit Prose”, 2016, University of Chicago Press.

  • jonathanpulliam

    Schrodinger’s cat in the hat


    Ah, yes, this is a really big problem. If those documents are to have any future merit to solve a medical condition or give us a clue to solve some new humongous technological discovery, then not only we but they themselves will loose out for the authors of even the white papers do not even to care about obeying to the rules of spelling and/or grammar.

    • Malatrope


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  • Ivan Alekseichuk

    I think one major co-variate was overlooked in this study: the English-language science become way more global over the time of observation. More and more articles are written by non-native speakers, who (1) don’t have a feeling of what is the “common” and “uncommon” language, but who rely on dictionary and typical language of other papers on the field. (2) Non-native English speakers may come from the cultures where longer sentences are common. Besides that, penetration of mathematics / complex statistics into biomedical papers is also growing over time, and that is not an easy text for the “general public”, no matter how one will write it. Finally, I am somehow not sure that a typical scientific paper that discuss certain hypothesis should become a basis of public opinion (i.e. should be read by non-specialists), at least till the point when the general agreement on the field regarding this hypothesis would be made.

    • Shawn P. Mitchell

      Excellent points Ivan. :)

    • Paul Rain

      Please to be doing the needful and editing your comment into two paragraphs.

    • smut clyde

      Also, with alacrity.

      It turns out that “alacrity” is not a herb, similar to coriander, used in the distillation of Akvavit. I am disappoint.

  • Shawn P. Mitchell

    “Publish or perish” is a phrase commonly used in academic circles. It describes the pressure to regularly produce content for publication. If they don’t, they risk losing out on tenure-track positions.

    This pressure seems to be affecting the quality of academic content. By using bigger words and longer sentences, researchers must feel that their chances for publication in a respectable journal will increase.

    Perhaps journal editors should include the Flesch Reading Ease score in their acceptance metrics?

    By the way, this comment earns a ‘B’ score on the Flesch Reading Ease measurement. It started out at a ‘D’. I’ll be the first to admit that it’s not easy! :)

  • OWilson

    The English language allows a superlative way to express oneself, if used properly.

    The use of proper English grammar is on the decline however.

    As someone who has marked “A” level English papers in the U.K., I found that even the test setters could not clearly propose the questions to be answered.

    Your child most often asked homework question is likey to be, “What do they MEAN, here?”

  • polistra24

    Readability and vocabulary are NOT the same variable. Specialized subjects require multisyllabic words, but they don’t force you to write in tangled sentences or use words like ‘oneself’.

  • Murar Yeolekar

    Excessive structuring and specified formats can contribute to less readability. One interested should not only ‘read the paper’ , but also enjoy the reading. Certain topics / issues loaded with statistical and mathematical details may turn ‘drab ‘ , but there may be few options.

  • jrkrideau

    I blame, partly jokingly, the decline of Latin studies.

    I have the impression the students in high school are not learning the structure and components of English.

    • Uncle Al

      Social intent says, “my ignorance is better than your knowledge. Anything else is hate language.”


    • smut clyde

      the decline of Latin studies.

      studia, studiōrum, studiīs, studia, studiīs, studia.
      I’ll show myself out.

      • jrkrideau

        smut delenda est?

  • Lee Rudolph

    The pre-eminent “Texas topologist” R. H. Bing, in section 5 of his review paper “Decompositions of E³” (1961), wrote a couple of paragraphs that may be marginally relevant here (the first lays the ground for the second).

    In a paper called “Continuous Transformations Preserving all Topological Properties” [23], James F. Wardwell raised the question as to whether each pointlike decomposition of a space yields the space as a decomposition space. One might wonder what mappings preserve all topological properties. A map of an object onto itself does this. The title is catchy.

    In contrast to such an attractive title are the non-revealing ones which some mathematicians use. One may conjecture that many mathematicians communicate their results with a care that varies inversely with their chances of being seen. They give details of proof with great care (as they should)—though few readers may actually read these details. But abstracts presented before the [American Mathematical S]ociety (when the author has at least a skeleton audience—perhaps a larger audience than reads less important papers) are frequently ill-prepared, apparently with no purpose of making a meaningful impression. Professor Tomlinson Fort once remarked that if newspaper editors showed the same lack of imagination in titling their articles, the headline above a story about a great calamity might read “Concerning a certain unfortunate event.”

  • Paul Rain

    Isn’t some degree of this inevitable though?

    I mean, we have scientific fields where core concepts didn’t exist a century ago. Yes, some of the descriptions of the concepts that have developed might be ‘jargony’. But some of this is the development of a new culture and language around a new field of study.

    And I’m sure a lot of the rest of the increase in complexity is simply down to the increase in the complexity and specialisation of the studies. You can’t publish on things we already know- you need to get your description of the ‘basics’ out of the way as concisely as possible* and then describe whatever iterative thing you’re doing as descriptively as possible.

    * which means you will end up using complex words

  • siempre44

    So the issue that is making the papers “less readable” is…the ignorance of language on the part of the reader?
    I thought I would be reading that the now common use of obscure, computer driven statistics is what makes many papers obtuse.
    To be told the issue is reader basic vocabulary is just sad.

  • Andrew

    The first thought that came to mind was a kind of backward movement from what the bible went through. For so long, it was only readable by clergy and then Luther made it available to the masses by translating to plain language. This is going from plain language to ‘high science speak’. But…science does bear a lot of similarity to religion after all anyway 😉

  • smut clyde

    Use one long word instead of two simple words.
    CON: Paper becomes unreadable.
    PRO: Paper slips in below word limit.

    Life is full of difficult decisions.

  • JPW

    Bullsh!te is typically deliberately complex.

  • RogerSweeny

    “Scientific papers are getting less readable” says the headline, but the text says that Abstracts are getting less readable.

    Two different things. It is probably orders of magnitude easier to analyze 709,577 abstracts than 709,577 whole articles, but it’s also easier to look under the lamppost.

    • Neuroskeptic

      Good point, there is a difference between abstracts and full texts. The authors addressed this by looking at readability of abstracts and full texts for 6 journals that make full texts available on PubMed. There was a fairly strong correlation

      “there was a strong positive relationship between readability of the abstracts and the full texts: FRE: r = 0.60, 95% CI [0.60, 0.60], p <10-15; NDC: r = 0.63, 95% CI [0.63, 0.63], p <10-15"

      These were not the same journals as in the rest of the analyses, however, and I don't think they spanned the same time period (because most OA journals are young.)

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  • Andrew K Fletcher

    If you can’t blind them with science, baffle them with BS

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Neuroskeptic is a British neuroscientist who takes a skeptical look at his own field, and beyond. His blog offers a look at the latest developments in neuroscience, psychiatry and psychology through a critical lens.


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