Grammar Considerations
in Scientific Writing
If any man wish to write in a
clear style, let him first be
clear in his thoughts
Johann Wolfgang von Goethe
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Writing the First Draft
Organize and Plan the Content
Matters of Authorship
Follow Standard Structure
Build Momentum and Keep it
Reserve a block of time for writing (3-4 hours every day for 4-5 days).
Write when your energy is high, not when you are tired or distracted.
Surround yourself with everything you need to write effectively.
data, drafts of figures and tables, references, computer or paper, coffee…
Work in a quiet place where you will not be interrupted.
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Building and Keeping Momentum
In scientific writing, each sentence depends on those around it and on other
sections of the paper. Therefore you need to sustain momentum when
writing your first draft. If you don’t, you’ll lose your train of thought!
Set realistic goals. This may be 1 page or 5 pages, but you want to end each
session with a sense of accomplishment.
End each writing session by writing into the next session. It will be easier to
start writing at the next session. This will help you maintain some
momentum and your train of thought.
Store your work from each session under a new file name.
Minimize distractions.
Don’t get stuck searching for the right word or phrase. If you can’t find what
you are thinking of in a minute or two, write “???” and continue on. You
can fill in the blanks later.
If you become bogged down and just can’t move forward with a particular
section, start working on another section.
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The Approach to Writing
Write the easiest section first.
For many authors, this is the Methods section.
Results is often the next easiest section to write.
Lay your data and figures out in the order you want to discuss it. Then write
the story of why you decided to do a particular experiment and what the
results were.
Think of each section as a separate task. For example, once the Methods is
written, one task is done.
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Revising the First Draft
As soon as you finish writing the first draft, revise it.
Revision gives you the luxury of considering specific issues on each pass.
One revision might be to establish parallel heading structures, another might
be for conciseness, while yet another might be for clarity of figures and tables.
In some paragraphs you may have written the supporting details first and the
message last. This is a natural way to write because you are discovering
what you think. However, this type of organization is difficult to read so,
during the process of revision, move the message to the beginning of the
paragraph (topic sentence) and put the supporting details after the topic
sentence.
During later stages of revision look for all possible ways to condense your
paper. Omit unnecessary words, details and paragraphs.
To decide whether a word, detail or paragraph is necessary, think of yourself
as the reader. Would I want to read this paragraph? Would I need to read
this paragraph? Be honest. If the answer is no, omit the paragraph.
Most readers prefer short, meaty and clear papers. Have the courage to make
your paper short, meaty and clear.
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First Orders of Concern
Question: The question is your main point. It is what the paper is all about. You must
make sure the question is present and clear. Is your question specific enough for
the scope of your paper? Does your paper focus on answering your question or
does it wander?
Introduction vs. Conclusion: Read your introduction and conclusion without
looking at the rest of the paper. Do they match? Sometimes authors start with
one question and end up with another. Be certain that ideas in your introduction
and conclusion are consistent. Otherwise your paper’s argument will not be
consistent and your readers will be confused.
Organization: Do you present ideas in a logical and clear manner? Are your main
points connected and do they have a clear connection to your question? Check
to see if ideas seem disconnected or if evidence falls under the wrong topic
sentence. The better your organization, the easier it will be for your reader to
understand the content of your paper.
Audience: Who is your audience? Is your manuscript appropriate for them? Your
audience should determine the tone and purpose of your manuscript.
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Second Orders of Concern
Topic Sentences: Does each paragraph have a topic sentence clearly stating that
paragraph’s main idea? If paragraphs do not have a central point, or if the
central point is not stated in a topic sentence, your audience will not understand
the purpose of the information they are reading. If the topic sentences are
present, is their relationship to your thesis clear?
Support/Evidence: Does each paragraph have evidence or proof supporting the
topic sentence? If a paragraph has a focus but no evidence then the point is not
supported—it’s just opinion. Be sure to support each idea in your essay with
specific details.
Documentation: Is all your evidence documented? It is plagiarism if you use
quotes, paraphrasing, or other evidence without citation. Make sure all of your
evidence is correctly cited using a standard citation style.
Clarity: Will your essay be clear to your audience? Are all of your ideas and terms
clear and well defined? Remember, writing is a form of communication limited to
what is on the page. Your readers cannot ask questions if they do not
understand. Take time to explain each point. Ensure that your reader can
understand exactly what you mean.
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Third Orders of Concern
Grammar, Punctuation, and Spelling: Although mechanics such as grammar,
punctuation, and spelling are at the bottom of the list of concerns, they are
very necessary. If a manuscript has great ideas but cannot be understood
by readers because of grammar, punctuation, and spelling, then the paper
has failed. Pay close attention to these details in the final drafts of your
document.
Voice: How would you describe your narrative voice? How you phrase your
writing influences how your audience will respond to what they read. Keep
your readers’ attention by avoiding the passive voice, jargon, and extra
wordiness.
When should you stop revising? When you are nitpicking over things such as
a word here and a comma there.
Strive for perfection, but be content with success !
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Readability - Sentence Length
The optimal sentence length for most scientific documents is 15 – 20 words
Variation in sentence length and complexity helps to sustain reader interest
If the two parts of a long sentence contain loosely- or un-connected thoughts, they
should be split into 2 separate sentences
Example:
An overly long sentence with weak connections: Exposed mice developed enteric disease
and exhibited 21% mortality during the first 3 weeks but controls had no enteric disease and
exhibited no mortality; 20-day old exposed mice weighed 0.6 g less than controls and had a
higher incidence of angular limb deformities and also had a greater incidence of rotated tibias
and showed bowed tibias, while controls had a significantly higher measurement for tibial
shear strength. (69 words in 1 sentence)
Separated at weak connections, then edited for wordiness: Exposed mice developed
enteric disease with 21% mortality during the first 3 weeks. Controls exhibited neither enteric
disease nor mortality. At 20 weeks, exposed mice weighed 0.6 g less, had more rotated and
bowed tibias and angular limb deformities, and showed significantly less tibial shear strength
than did controls. (44 words in 3 sentences; average 18 words per sentence)
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Paragraphs
Goals of a paragraph are to get a message across and to make the story
behind the message clear.
These goals can be accomplished in various ways, but the general approach
is to provide an overview first, and then give details; that is, create an
expectation and then fulfill it.
Should be organized
Should have continuity
Should emphasize important information
Organization
Give overview first, in a topic sentence. Introduce key term(s).
Give details, in logically organized supporting sentences
Do not omit any steps in the logic
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Limit Average Paragraph Length
Paragraph length and complexity influence readability.
An average paragraph length of about 150 words has been judged optimal for
most scientific articles.
Paragraphs consistently composed of 50 words or less create a text that is too
choppy.
Paragraphs should generally contain at least 3 sentences; a topic sentence at
the beginning, a concluding sentence at the end, and a content sentence
in the middle.
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Readability Statistics
Tools > Options > Spelling and Grammar > Show readability statistics
When the readability box is
checked, these statistics will
appear after you complete a
spell check
Continuity and Clarity in Paragraphs
Repeat key terms
Repeat exactly
Repeat early
Example: Digitalis increases the contractility of the mammalian heart. This
change in inotropic state is a result of changes in calcium flux through the
muscle cell membrane.
What is “inotropic state? How does it relate to the previous sentence? The
answer is that “contractility and inotropic state mean the same thing. Why
confuse the reader with different terms?
Revision: Digitalis increases the contractility of the mammalian heart. This
increased contractility is a result of changes in calcium flux through the
muscle cell membrane.
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Revise for Clarity
Clarity can be thought of as “grace of expression”, it means going beyond
technical correctness, in an effort to meet the needs and comfort of the
reader.
Although content of the document is more likely to determine whether it is
accepted for publication than its prose style, gracefully written text gives
readers a sense that the author has mastered his or her subject.
Know the difference between generality (good) and vagueness (bad).
Vague – “These results have important implications for regulation of
splicesosome assembly”
General – “Because it is involved early in the splicesosome assembly
pathway and affects downstream processes, protein X is an
important regulator of splicosome assembly”
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Revise for Brevity
Have you ever received a comment like this from a journal editor or reviewer?
“Shorten this manuscript considerably before resubmitting it”?
Fortunately, this can be done without removing significant material from the
text and in the process, the content often becomes clearer.
Example:
Tamoxifen could conceivably slow the growth rate of the tumor. In doing
this, a substantial protection of the tumors from the effects of cytotoxic
chemotherapy might ensue.
(27 words)
Revised:
Tamoxifen could slow the growth rate of the tumor, thus making it less
sensitive to cytotoxic chemotherapy.
(17 words)
When you revise for brevity, clarity is often an added bonus.
When clarity and brevity conflict, clarity is more important than brevity.
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Active vs. Passive Voice
Passive voice implies that the subject of a sentence is being acted upon.
Active voice shows the subject of the sentence directly doing the action.
Active: The receptor can still bind DNA, and constitutively activates estrogenresponsive genes.
(87 characters, 12 words)
Passive: The receptor is still able to bind DNA and is constitutive for activation of
estrogen responsive genes.
(102 characters, 17 words)
Passive voice can be weak and boring.
Most journals now prefer scientists to use active voice. After all, you did the work, and you
are drawing inferences from it. It is important to be able to write in both active and
passive voice. Passive voice is often used in the methods and results sections and
active voice in the more interpretive introduction and conclusion sections. Varying voice
throughout sections is seen commonly, and keeps the work faceless but attaches a
personal voice to the ideas driving the work. Active voice usually requires fewer words
and allows shorter sentences.
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Connections
Shorter, but choppy and difficult for reader to see relationship between
sentences:
MDA-231 cells secrete a TGF-α-like activity. They contain no classical 6
kDa TGF-α. They synthesize a 30 kDa protein molecule which binds to the
EGF receptor. The EGF receptor mediates TGF-α activity.
Longer, but smooth and easy for reader to see relationship between
sentences:
MDA-231 cells secrete a TGF-α-like activity, but they contain no classical 6
kDa TGF-α. They do, however, synthesize a 30 kDa protein that binds to the
EGF receptor, the receptor that mediates TGF-α activity.
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Hedging
“Hedging” is a way to protect your arguments or statements from unknown
contingencies. It also provides a way to avoid commitment to your ideas.
However, each use of a hedging qualifier drains force from your sentence.
Sometimes the result is a sentence that says nothing at all.
Example:
The cause of the degenerative changes is unknown but possibly one
cause may be infection by a presumed parasite.
One way of saying “I’m not sure” is usually enough. Try to omit all but one
hedging word from a sentence, unless they are needed for accuracy.
Improved: Parasitic infection may cause degenerative changes.
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Parallelism
Parallel ideas are equal in logic and importance.
Examples of parallelism include ideas that are joined by "and," "or," or "but“, as well as ideas
that are being compared.
Parallel ideas should be written in parallel form, either in pairs or in series.
Parallel form is the use of the same grammatical structure for two or more parallel ideas.
The value of writing parallel ideas in parallel form is that the form of the first idea prepares the
reader for the form of the next idea. As a result, readers can concentrate all of their
attention on the ideas, not on the form.
Example: Contrasting ideas Joined by “but"
Cardiac output
decreased
blood pressure
decreased
subject
verb
by 40%
by only 10%.
prepositional phrase
but
In this example, the group of words after "but" is in the same grammatical structure as the
group of words before "but": (subject, verb, prepositional phrase).
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Parallel Lists
More than two ideas can be presented in parallel form.
Example: We washed out the lungs five times with solution I,
instilled 8-10 ml of the fluorocarbon-albumin emulsion into the trachea,
and incubated the lungs in 154 mM NaCl at 37oC for 20 min.
Example: The best way to remove nonadherent cells was
to tip the plate at a 45o angle,
to flood the top edge of the plate with 3-4 ml of medium,
to remove the medium, and
to repeat this procedure until almost all the floating cells were removed.
An advantage of parallelism is that it allows you to avoid repetition
Example: Pulse rate decreased by 40 beats/min, systolic blood pressure declined by 50
mmHg, and cardiac output fell by 18%.
Revisions: Pulse rate decreased by 40 beats/min, systolic blood pressure by 50 mmHg,
and cardiac output by 18%.
Pulse rate, systolic blood pressure, and cardiac output decreased by 40 beats/min, 50
mmHg, and 18%, respectively. (not good: confusing)
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Comparisons
Overuse of "compared to,"
In comparisons containing a comparative term, such as "higher," "greater,"
"lower," "less," the accompanying term should be "than," not "compared to.“
Example: We found a higher KD at 37oC compared to 25oC.
Revision: We found a higher KD at 37oC than at 25oC.
Example: Experimental tissues had a 28% decrease in phospholipid as
compared to control tissues.
Revisions: Experimental tissues had a 28% greater decrease in phospholipid
than did control tissues. (decrease in both groups)
Experimental tissues had a 28% decrease in alveolar phospholipid but control
tissues had no decrease. (decrease only in experimental tissues)
Experimental tissues had 28% less phospholipid than did control tissues.
(decrease in neither group)
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Verb Tense
When scientific knowledge has been published in a primary journal it
becomes standard knowledge and should be referred to in the present tense.
Examples:
Serological tests commonly are used to diagnose HIV infections.
Several recent reports describe similar findings.
The investigations of Graff (2002) show that the structure is a true icosahedron.
This phenomenon determines the absorption coefficient of the tissue.
Section
Purpose
Tense
Abstract
Primarily refers to the author’s unpublished results
past
Introduction
Emphasizes previously established knowledge
present
Methods
Describes what the author did and found
past
Results
Describe what the author did and found
past
Discussion
Discusses the relationship of the author’s work
to previously established knowledge
past and present
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Number Use
Use numerals to express numbers 10 and above.
Use words to express numbers below 10.
Use numerals when you have 3 or more numbers in a series, even if each
of the numbers is below 10.
Use a combination of words and numerals in the following situations:
large rounded numbers: a grant budget of $1.5 million, 4 thousand species
units of measurement: two 13 ml aliquots
confusing combinations: twenty 6-year-old patients
more than two numbers in a string: six 3-5 day intervals
When numbers begin a sentence you must write them out in words.
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Word Choice
Written language is much different than spoken language.
In spoken language, phrases and ideas are often repeated in order to give the listener
additional clues to the message.
In written language, a reader can, if necessary, reread a passage. Inflection and timing
clues are absent. Meaning depends entirely on word choice.
Qualitative words that describe magnitude are imprecise and therefore of little value when
used alone.
Example: Heart rate increased markedly.
What does "markedly" mean? We need data to know how big the increase was. If you use
a qualitative word such as "markedly," quantify it either by citing a figure or a table or by
reporting the data in the text. The best policy is to avoid qualitative words completely in the
Results section. Save qualitative words for the Discussion, for occasions when you need to
emphasize the magnitude of a change or a difference.
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Precise Word Choice
Example: Ability versus Actuality
Ability: We could not demonstrate high-affinity, low-capacity IL-2 receptor
binding sites.
"Could not demonstrate" implies that binding sites may have been
present, but the technique was not sensitive enough to detect them.
Actuality: There were no high-affinity, low-capacity IL-2 receptor binding sites.
"There were no" implies that no binding sites exist (so no method
would be able to detect them).
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Precise Word Choice
Example: p53 phosphorylation did not increase.
"Did not" implies no expectation
p53 phosphorylation failed to increase.
"Failed to" implies an expectation that the value should have
increased, but didn’t.
Unless you have a reason to expect a certain result, you should use the neutral
description, "did not increase," when reporting results.
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Which and That
A phrase introduced by “that” is restrictive and cannot be omitted without
changing the meaning of the sentence.
Such essential material must not be set off by commas.
Example: Animals that were treated with antibiotics recovered.
A nonrestrictive phrase adds information, but does not limit what it modifies.
Because it can be omitted without changing the meaning, it is set of by commas.
“Which” should be used to introduce a nonrestrictive phrase.
Example: The committee’s decision, which did not come easily, was final.
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Uses of i.e. and e.g.
i.e., id est, means “that is to say,” and references words synonymous
with the preceding statement. Its use implies that the explanation you
are making is the only possible explanation.
Example:
He did not respond (i.e., he declined).
e.g., exemplia gratia , means “for example,”. Its use implies that the
explanation you are making is one of many possible explanations.
Example:
You should get her a small gift (e.g. a flower or plant).
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Commas
Use commas:
To prevent false joining:
Example: Although monensin was discontinued after 9 days the fermentors resumed gas
production.
This sentence can be interpreted at least two ways:
Although monensin was discontinued, after 9 days the tumors regressed.
Although monensin was discontinued after 9 days, the tumors regressed.
For clarity and emphasis:
Use commas to set off a clause that is not required in the sentence.
Example: The cells, which came from six different labs, did not express BRCA1.
To punctuate elements in a series:
Place a comma before the and or the or, as well as between the items.
Example: Following centrifugation, pellets were washed, resuspended in 5 ml of buffer D, and
disrupted by homogenization.
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Make your Document LOOK Good
Left justify all paragraphs unless specifically instructed otherwise.
Bold all subheadings.
Double-space between all sentences.
Put a space between paragraphs.
Insert a page break between major sections.
Spell check and grammar check.
Use a serif font (i.e. Times New Roman, Garamond) for printed text.
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Get Feedback
Get at least one colleague to read your paper and make suggestions.
Pick someone who will be honest and who will provide constructive feedback.
Be prepared to accept the criticism.
It is most beneficial to find someone who will give you lots of comments and
constructive criticism.
If your colleague returns the paper to you with only a few minor comments,
find someone else.
Carefully consider all comments and criticism, but don’t feel obligated to
incorporate all suggestions into your paper.
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Reviewer Evaluation Form – J Biomedical Science
1. Is the title clear and precise?
2. Is the Abstract descriptive of contents?
3. Are enough details presented in the Methods section?
4. Are adequate statistical evaluations of data provided?
5. Are the Figures and Tables of suitable clarity and quality?
6. Is the Discussion section pertinent to the main theme of the
article?
7. Are conclusions justified by the data?
8. Are adequate and correct references provided?
9. Could the article be improved by shortening?
10. Are organization, style and grammar satisfactory?
__ Yes __ No
__ Yes __ No
__ Yes __ No
__ Yes __ No
__ Yes __ No
__ Yes __ No
__ Yes __ No
__ Yes __ No
__ Yes __ No
__ Yes __ No
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Additional Appendix Material
Journal Impact factors for 2005
http://gezhi.org/wp-content/uploads/2006/06/2005%20SCI.zip
Tools > Options > Spelling and Grammar > Show readability statistics
When the readability box is
checked, these statistics will
appear after you complete a
spell check
Revising Structure
Is the title accurate, succinct, and effective?
Does the abstract represent all of the content within the allowed length?
Does the introductory material set the stage adequately but concisely?
Is the rest of the text in the right sequence?
Is all of the text really needed?
Is any needed content missing?
Do data in the text agree with data in the figures and tables?
Are correct references included?
Should any of the figures or tables be omitted? Restructured? Combined?
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Active vs. Passive Voice
Vague Passive Phrasing
Active, Precise Wording
It is recommended by the authors of the
present study that ...
We recommend .. .
The animal was observed to be situated in
dorsal recumbence, which had the effect
of rendering its legs useless.
Lying on its back, the animal could
not use its legs.
The data, which were obtained by Hwang,
were probably indicative of. . .
Hwang's data probably indicate .. .
The following results were obtained ...
We obtained these results .. .
It was discovered that a sustained
coordinated effort will be required ...
We need a sustained coordinated effort.
X may be done
X will be done
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Verb Tense
Verb Tense
Statement
Example
Present
Question
Known
"whether X increases Y"
"X is a component of Y"
Present perfect
Transition clause
introducing something known
"It has long been known that”
Present or
present perfect
Unknown
"X is unknown"
"X has not been determined"
Past or present
Signal of the question
"We hypothesized that..."
"The purpose of this study was...”
"We asked whether...”
but "This report describes”
Simple past
Experimental approach, and anything
else done by you or others in the past
"we assessed"
Hypothetical
Suggestions, possibilities
"X may have an effect on..."
"X might reduce..."
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Situations in which Numbers Should be Given as Numerals
General Guideline
Examples
All numbers 10 and above
Trial 14; 35 animals; 16 genera of legumes
All numbers that immediately precede a unit of
measurement
A wing 10 cm long; 5 mg of drug; 21days
Numbers with decimals; fractions that include
whole numbers
7.38 mm; 41/2 hours
Numbers that represent statistical or mathematical
functions or results, percentages, ratios
Multiply by 5; fewer than 6%; 3.75 times
as many; the 2nd quartile
Numbers that represent exact times or
dates; ages; size of samples, subsamples or
populations; specific numbers of subjects in an
experiment; scores and points on a scale; exact
sums of money; and numerals as numerals
About 3 weeks ago, at 1:00 a.m. on January 25,
2000, the 25-year-old patients with IQ scores
above 125 all awoke simultaneously in the
nursing home at 125 Oak Street. They were
paid $25 apiece to go back to sleep
Numbers below 10 that are grouped for comparison
with numbers 10 and above in the same paragraph
4 of 16 analyses, the 1st and 15th of the 25
responses; lines 2 and 21
Numbers that denote a specific place in a numbered
series, parts of books and tables, and each
number in a list of four or more numbers
Trial 6; Grade 9 (but the ninth grade); the groups
consisted of 5, 9, 1, and 4 animals respectively
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Situations in which Numbers Should be Written as Words
General guideline
Examples
Numbers below 10 that do not represent
precise measurements; numbers used in an
indefinite, approximate, or general manner
Five conditions; trials were repeated four
times; a one-tailed t test; a three-way
interaction; about thirty years old
Numbers below 10 that are grouped for
comparison with numbers below 10
The second of four stimuli; five of eight
living animals; in six cases, the disease
lasted five times as long as in the other four
Any number that begins a sentence, title, or
heading (but reword to avoid this whenever
possible)
Fifteen patients improved, and five did not.
Sixty-nine percent of the sample was
contaminated
Common fractions (those without whole
numbers)
One quarter; reduced by half; a threequarters majority
The numbers zero and one when words
would be easier to comprehend than
figures, or the words do not appear in
context with numbers 10 and above
A one-line computer code; zero-based
budgeting; one animal gave birth (but
only 1 in 18 gave birth)
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Suggestions to Replace Common Overused Words and Phrases
Instead of
at this point in time
dorsal or lateral recumbency
due to the fact that
employ, utilize
high degree of accuracy
implement
in the event that
method
neonate
oftentimes
plethora
postoperatively
prior to
retard
subsequent to
utilize
Use
now
on its back or side
because
use
accurate
do
if
way
newborn
often
excess
after surgery
before
slow
after
use
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Hedging Words Commonly used by Biologists
and Medical Researchers
Nouns
Adverbs
Verbs
supposition
presumably
appear
idea
probably
postulate
speculation
possibly
suggest
conjecture
apparently
seem
possibility
not unlikely
may be
inference
seemingly
speculate
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Examples of "it ... that" Phrases that can be Removed or Replaced
Phrase with Empty Fillers
Shorter Equivalent
It would thus appear that
Apparently
It is considered that
We think
It is this that
This
It is possible that the cause is
The cause may be
In light of the fact that
Because
It is often the case that
Often
It is interesting to note that
omit
It is not impossible that
omit
A not unlikely cause could be that
omit
It seems that there can be little doubt that
omit
In order to
To
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Brevity
Needless repetition of an idea in a different word, phrase, or sentence should
be eliminated. Remove words that do not change the meaning of a sentence.
Examples of Redundant Words; Omit the red Italicized Words
continue on
refer back
check up on
all of
true facts
enter into
face up to
count up
five in number
1 a.m. in the morning
at this point in time
collaborate together
circulate around
end result
mandatory requirement
new beginning
optional choice
prioritize in order of importance
positive benefits
true facts
large in size
many in number
red in color
repeat again
past history
complete stop
in order to
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