Before you begin
If you know the journal your paper, or your client’s paper, will be submitted to, you should look over an article of the same type from the target journal. In particular, pay careful attention to whether the journal encourages the use of first versus third person, active versus passive voice, past versus present tense, how the tables and figures are formatted, and length restrictions.
Voice refers to whether a subject acts (active voice) or is acted upon (passive voice). Traditionally, scientific papers have been written primarily in a passive voice. For most journals, however, it has become acceptable and even encouraged to use active voice where passive voice would be awkward. It is especially common to use active voice syntax in the Results and Discussion sections, specifically when the author is distinguishing what they did relative to what others did, when the authors are distinguishing their view in a debate, or when the authors are describing a technological innovation developed in their own laboratory. Passive voice is more commonly used in the Abstract and Methods, with some journals explicitly discouraging its use.
Although papers are customarily heavy on passive voice, largely related to the convention of using the third person and creating a sense of objectivity, active voice is always preferred when it is feasible. For example, the active and direct ‘Group X did not differ from the control group’ is preferred to the passive ‘No significant difference was observed between Group X and the control group’. Making writing in the active voice a habit can take some practice, but it can make papers much clearer and more concise when used properly.
Past tenses are predominant in biological and medical papers reporting experiments conducted in a laboratory, in the field, or in a clinic. This convention is especially true in the Methods and Results: procedure x was performed and data y and z were observed. Present tenses are predominant in proof reports, such as in Applied Mathematics and Social Sciences, when the author is actually leading the reader through a thought demonstration: ‘Substituting constant k’ for formula f’, it can be seen that variable D becomes negligible’; ‘Hence, this demonstration that assumption A is invalid proves that hypothesis H is false’. Past perfect (have done) and present tenses are appropriate for explaining the status quo of knowledge: ‘Icon and colleagues have demonstrated the validity of this model in rodents and primates’; ‘The laparotomy approach is the gold standard for this procedure’; ‘The Earth is not flat’. Present perfect, present subjective, and future tenses are appropriate for examining implications and making recommendations: ‘Surgeons should be particularly mindful of this possibility when operating on patients with a BMI over 35’; ‘These findings will provide a basis for changing life as we know it’.
There is something very satisfying about reading a clear and succinct presentation of ideas. Readers should not have to work to comprehend what the author is trying to say. One important example of this issue that should be fixed is the use of comparator terms without reference to what the subject is being compared. When terms such as “greater” and “lesser” (and –er words in general) are used, it should be explicitly stated greater than what. Likewise, it should be clear what statistical comparisons were done.
While it is grammatically acceptable to leave out some words– that is, in syntactical terms, to use elliptical phrasing– it can create confusion in technical writing, especially when there are multiple entities being related to one another. If a sentence could be interpreted in more than one way, then the missing words should be inserted.
Modifiers: Clauses, phrases, and appositives
An exhaustive discussion of all of the different types and subtypes of modifiers can be found in the Tameri Guide for Writers (or other grammar-dedicated resources). Here, I will speak of ‘modifiers’ as a group.
Text providing further explanation/definition of something within a sentence should, whenever it is possible, be immediately adjacent to the subject being described. This practice eliminates “dangling modifiers” (i.e. modifiers that are out of place and therefore confusing). When located at the beginning of a sentence (such as here), modifiers should be followed by a comma. In similar fashion, when located in the middle of a sentence (such as here), nonessential modifiers should be set off by commas before and after.The rule is that if the modifier could be removed and the sentence would still make the critical point then it is nonessential, and thus should be set off by commas. Commas are not needed if the modifier is essential to the critical point of the sentence. That being said, essential modifiers can often be replaced with a more succinct adjective or adverb. For example, “the students who work hard will earn good grades” would be better said as “hard-working students will earn good grades”.
Prepositional phrases, especially, should often be removed in favor of simple adjectives where possible, especially in sentences where there are strings of them. This process goes hand in hand with making one’s language more direct. For example, “increased expression of mRNA from XYZ gene of mammals was found” would be better as “mRNA expression of the mammalian XYZ gene was increased.”
If the author is trying to pack multiple modifiers into a sentence, it can be a great improvement to break out one or more of the modifiers to form separate sentences. Likewise, if the relationship between sentence components is not obvious, the sentence needs to be broken up to clearly communicate those relationships. In many cases, direct objects may need to become the subject of a new sentence to achieve this. If the relationship cannot be deciphered, insert a comment advising the author that they need to provide this information to make the sentence readily understandable.
Authors should come across as refined in writing published in professional publications. It is important to not overstate conclusions or the certainty of suggested explanations. When suggesting a potential mechanism or explanation, it is helpful to use “may” terminology, as well as terms such as putative, possible, proposed, likely, could be, etc. Likewise, when an author is debating a point, the language needs to be respectful and objective.
Use pronouns with care
Pronouns (it, this, that, those, these, etc.) should only be used when the nouns to which they are referring are obvious. If ever the intended noun is dubious, the object should be restated. For manuscripts being submitted to scientific journals and theses/dissertations, the best practice is to always specify a noun after this/that/those/these. For example, rather than saying “this suggests”, say “this finding suggests”.
Spell out contractions
Contractions (don’t, isn’t, can’t, etc.) simply DO NOT BELONG in (most) formal writing.
Do not split infinitives
In formal writing, the rule of keeping the infinitive intact should be heeded:
Questions should be rare (for emphasis) or avoided altogether in academic writing. Look for ways to reword questions as sentences. You can usually state what is unknown or what hypotheses/possibilities/uncertainties will be examined.
Semi-colons should only be used when using commas is too confusing. Whether you are using commas or semi-colons, all items in the list should be similarly conjugated. Although dropping the last comma in a list or series before the word “and” (a.k.a. serial comma or Oxford comma) is common, it can create confusion—especially if the items in the list are phrases that include the word “and” themselves.
Proper nouns loose the capitalized status when they become adjectives: Parkinson disease -> parkinsonian gait.
To maintain the level of formality appropriate for scientific discourse, revise colloquial expressions:
If you ever have the sense that a part of speech is missing, but you cannot find the word consider these: item, entity, process, phenomenon, individual, each, eventuality, process, existence of, presence of, organism, unit, component, portion, presence/absence of, excess/dearth of, peak/nadir, etc. It can also help to put in missing there is/are, in which, that is/are, which is/are.