Proofread as a task with its own techniques
Proofreading is the final check that catches the spelling, grammar, formatting and consistency errors a document still carries. It is prepared before the reading starts, uses techniques that stop the brain filling in what it expects to see, and looks for particular kinds of error, and the skill grows with experience of different kinds of content.
What proofreading asks of the proofreader
Medical writers and editors are expected to be excellent proofreaders, able to identify and remedy mistakes such as grammatical, spelling or formatting errors. A large part of many writing and editing roles involves proofreading and editing text to a high standard. Whether the piece is a manuscript or abstract for a journal, a conference poster or a sales aid for healthcare professionals, picking out and correcting errors easily and efficiently is key, because the proofreader is the last line of defence against glaring spelling errors, inconsistencies and awkward grammar. Once a piece of writing seems ready to submit, a final step is to proofread it for mechanical errors that went undetected or were introduced. Online articles and books list the common errors to look out for, and these lists are useful, particularly at the start of a career, but memorising them may not be the most effective way to learn. Proofreading is a learning process: over time, with experience of different types of content, a proofreader becomes aware of the common errors to look out for and of the techniques that keep proofreading to a high standard.
Preparing to proofread
Steps taken before proofreading anything set the proofreader up to work efficiently and to spot and correct errors. Editing and proofreading require high focus and concentration, and before beginning the proofreader makes sure they are in an environment that fits their style of working. That varies between individuals: some prefer complete isolation, while others thrive in a busy coffee shop or elsewhere with background noise.
The proofreader also knows which medium, electronic or hard copy, they prefer and work best with. On hard copy it is often easier to see formatting errors such as different font sizes or styles, colour differences, and crop and bleed marks. A digital copy offers spelling and grammar checkers and find-and-replace for swift correction of common errors, and it shows subtle differences in line and paragraph spacing that a printout hides. Organisations and clients work differently, so the preferred medium will not always be available, and it is useful to have both. Once the proofreading is finished, a final check in the other medium is recommended: a digital copy is printed to find anything missed, and after a hard copy the digital version is opened to check line spacing and subtle font size differences that are difficult to notice on a printout.
The medium can also be changed on screen. One freelance writer saves her own Word and PowerPoint files as PDFs to proofread them, which differentiates them enough that she spots errors she would not have noticed in the native files. She reviews the PDF on one monitor and enters the edits directly into the native file on another, instead of printing the document, marking it with a red pen and then entering the edits, and so saves both paper and time.
Before beginning, the proofreader gets as much information as possible on the context of the document. A manuscript is more likely to use formal and technical language, while a conference poster for healthcare professionals uses more engaging wording and may use marketing terms to sell the piece, and the target audience may include non-native English speakers. Knowing the context helps keep the style and tone consistent throughout and appropriate for the intended audience; idioms, for example, should generally be avoided where the audience may include non-native English speakers.
Reading techniques
Reading silently makes it easier to check readability and sentence flow, but it may encourage skimming and unintentionally skipping small errors as the brain fills in the gaps. Reading aloud forces a slower reading without skimming, which catches the errors a silent reading may miss, and it can force the reader to notice every word, whether in a typescript or a proof. But punctuation marks are silent, so reading aloud does not help find incorrect uses of full stops, commas, exclamation marks and the like. Neither way of reading is therefore better, and doing both is recommended to identify as many errors as possible. Over time a proofreader may come to prefer one, but it generally does not hurt to do both.
The brain also fills in the gaps from context when reading forwards and meeting misspelled words, so reading a sentence backwards helps pick up spelling mistakes, although the sentence will not make sense. Reading a sentence or paragraph in isolation helps detect problems with readability or sentence structure. On screen, a paragraph break between sentences or wider line spacing isolates them, and on hard copy a ruler or piece of paper does.
Visual content such as a conference poster or a galley proof can often have styling inconsistencies where the style guide does not make clear which form is correct, such as how the authors' names and affiliations are written or the size of a logo. Where possible it is compared with a similar piece of work: a conference poster with the poster for the same meeting in a previous year, and a galley proof with a published article in the same journal.
Software can do the reading aloud. Listening to a text read aloud uses different cognitive processes from reading it on a page, and a study at the University of Perugia suggests that actively listening may lead to more intense and deeper information processing. Microsoft Word 2019 has a Read Aloud function that reads a Word file aloud, which can be useful for a quick pass to catch errors while the reader sits back and listens. It is on the Review tab and opens a sidebar with Back, Play or Pause, Forward, Settings and Exit controls, where Settings offers a choice of reading voices and reading speed. On catching an error, the reader pauses Read Aloud, makes the change, moves the cursor back to where reading should start and restarts it. Read Aloud must be paused or exited before any typing or editing, because the cursor tracks the reading and text can be deleted by accident. It also reads tracked changes as the text on the page, deleted text included, so it works best on a final copy without tracked changes.
Breaks and fresh eyes
Reading the same text repeatedly makes the brain skip words and phrases and reduces the ability to identify errors, so a break and a return with fresh eyes can be more effective. A day or more away is ideal, but deadlines do not always allow it, so even as little as 30 minutes away, walking or reading a book, can help; the key is to take the brain's focus away from the document. On an electronic copy, changing the font size, colour, and sentence or paragraph spacing also tricks the brain into thinking it is looking at something unfamiliar when the proofreader comes back to it. It may also be preferable to work in short blocks of time, as concentration and focus can wane over longer periods.
One editor, tired of proofreading her thesis endless times, saw assessmnet in capital letters on its title page at the last moment before sending it for printing, and was terrified, though the printed version read assessment.
Noting what to check later
While proofreading, the proofreader makes notes or a checklist of anything they are unsure about or need to check later. This is especially useful when working to a specific style guide, because moving back and forth between the style guide and the content can take the proofreader out of their focus on the content. It also prevents correcting what does not need correcting. If an author uses qd in the Abstract and Introduction and switches to once daily in the Methods, the inconsistency is noted and checked against the style guide later, which may well state that once daily is correct, so correcting to qd throughout because it came first would be wrong.
Errors to look for
The proofreader looks for typographical errors and is especially alert for typos that yield homonyms, such as to for too, or other actual words, since a spellchecker will not help if pubic was typed instead of public. Items prone to computer snafus during typesetting, such as specialised symbols and Greek letters, deserve extra attention. The proofreader is also alert for mechanical problems that escaped notice during editing, which may include misspellings, grammatical errors such as subject–verb disagreement, punctuation errors, omitted or duplicated words, and deviations from the requested style and format. Other problems to check for are errors in alphabetical or numerical sequence, incorrect arithmetic, inconsistencies of information and inaccurate cross-references.
A sentence can carry one such error or several, such as then for than, percise for precise, they're for their, a redundant more than before ≥50%, expereinced, between 18 or 35 years, wait for weight, enroled, ration for ratio, diarrhia, a confidence interval abbreviated CL in one place and CI in the next, and 95 without its per cent sign. Errors also lie in the inconsistencies between two paragraphs of the same manuscript.
In one pair of paragraphs, Phase 3 becomes phase III, in lower case and with Roman instead of Arabic numerals, and multicentre becomes the US spelling multicenter. Years, written in full in the first paragraph, becomes yrs, an age range takes a hyphen in one paragraph and an en dash in the other, and endpoint becomes end point, with an unnecessary space. Drug X also becomes drug X, and drug names are generally lower case unless the product is a brand.
In another pair, Month 12 is capitalised because it refers to a specific time point in the study, so the later month 12 is both inconsistent and incorrect. Twice-daily and b.i.d. mean the same, but interchanging them can confuse readers, so one style is preferable throughout. Patients and people are sometimes interchangeable depending on the context of the study, but switching between them could confuse readers and is usually better avoided. The spacing around the equals sign in n= values varies, and while the style guide decides, there are usually no spaces. N= is incorrect for a subgroup, because a capital N refers to the overall population and a lower-case n to a subpopulation. The P value style also differs, and although there is no one correct style, in the absence of a style guide the same style should be used throughout the manuscript.
Final checks
Once the bulk of the proofreading is done, it is always good to do a final check of the work to uncover any errors that might have been missed. A quick scan double-checks anything that looks odd or inconsistent, as there may be subtle errors, such as black against dark grey font colouring, that were not caught earlier. Digital spelling and grammar checkers are useful as part of the final checks, but they are not perfect and should not be relied on: they cannot discern between homophones, such as lesson and lessen, peak and peek or whether and weather, and they are not reliable for grammatical errors. If all the earlier steps have been followed, there should be very little, if anything, left for them to correct.
Microsoft Word's advanced proofing features can flag jargon, simpler language and passive voice with suggestions to accept or ignore, but they are hidden and not enabled by default. One medical writer runs a complete proofing check with them on all her writing, with every one of the more than 100 features selected. The style guide of the target publication or audience can help guide which suggestions to accept; passive voice, for example, may sometimes be acceptable in medical and scientific writing, so a suggestion against it is weighed for whether the passive is appropriate. The feature will not find everything that could be refined to make the writing clearer, it sometimes recommends changes that should not be made in the context of the document, and in her experience it still misses some grammar or syntax mistakes. Using it is a start, and a human may need to refine the text further.