The Structure, Format, Content,
and Style of a
of Contents | FAQs | PDF
Journal-Style Scientific Paper
a Scientific Format?
The scientific format
may seem confusing for the beginning science writer due to its
rigid structure which is so different from writing
in the humanities. One reason for using this format is that it
is a means of efficiently communicating scientific findings to
the broad community of scientists in a uniform manner. Another
reason, perhaps more important than the first, is that this format
allows the paper to be read at several different levels. For
example, many people skim Titles to find out what information
is available on a subject. Others may read only titles and Abstracts. Those wanting to go deeper may
look at the Tables
and Figures in
the Results, and so on. The take home point
here is that the scientific format helps to insure that at whatever
level a person reads your paper (beyond title skimming), they
will likely get the key results and conclusions.
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The Sections of
Most journal-style scientific papers are
subdivided into the following sections: Title,
Authors and Affiliation, Abstract,
Acknowledgments, and Literature
Cited, which parallel the experimental process. This is the
system we will use. This website describes the style, content,
and format associated with each section.
The sections appear in a journal style
paper in the following prescribed order:
Main Section Headings: Each main section of the paper begins with a
heading which should be capitalized, centered
at the beginning of the section, and double spaced
from the lines above and below. Do not underline the section
heading OR put a colon at the end.
Example of a main section heading:
When your paper reports on more
than one experiment, use subheadings to help organize the presentation.
Subheadings should be capitalized (first letter
in each word), left justified, and either bold
italics OR underlined.
Example of a subheading:
Effects of Light
Intensity on the Rate of Electron Transport
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Title, Authors' Names,
and Institutional Affiliations
1. Function: Your paper should
begin with a Title that succinctly describes the contents
of the paper. Use descriptive words that you would associate
strongly with the content of your paper: the molecule studied,
the organism used or studied, the treatment, the location of
a field site, the response measured, etc. A majority of readers
will find your paper via electronic database searches and those
search engines key on words found in the title.
- The title should be centered at
the top of page 1 (DO NOT use a title page - it is a waste of
paper for our purposes); the
title is NOT underlined or italicized.
- the authors' names (PI or primary
author first) and institutional affiliation are double-spaced
from and centered below the title. When more then two authors,
the names are separated by commas except for the last which is
separated from the previous name by the word "and".
Ducks Over-Winter in Colorado
Barley Fields in Response to
Increased Daily Mean Temperature
Ima Mallard, Ura Drake, and Woodruff
Department of Wildlife Biology, University of Colorado - Boulder
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The title is not a section, but it is
necessary and important. The title should be short and unambiguous,
yet be an adequate description of the work. A general rule-of-thumb
is that the title should contain the key words describing
the work presented. Remember that the title becomes the basis
for most on-line computer searches - if your title is insufficient,
few people will find or read your paper. For example, in a paper
reporting on an experiment involving dosing mice with the sex
hormone estrogen and watching for a certain kind of courtship
behavior, a poor title would be:
Why? It is very general, and could be
referring to any of a number of mouse behaviors. A better
title would be:
The Effects of Estrogen on the Nose-Twitch Courtship Behavior
Why? Because the key words identify a
specific behavior, a modifying agent, and the experimental organism.
If possible, give the key result of the study in the title, as
seen in the first example. Similarly, the above title could be
Estrogen Stimulates Intensity
of Nose-Twitch Courtship Behavior in Mice
for Writing Title.
An abstract summarizes, in one paragraph (usually), the major
aspects of the entire paper in the following prescribed sequence:
- the question(s) you investigated
(or purpose), (from Introduction)
- state the purpose very clearly in the
first or second sentence.
- the experimental design
and methods used, (from Methods)
- clearly express the basic design of the
- Name or briefly describe the basic methodology
used without going into excessive detail-be sure to indicate
the key techniques used.
- the major findings including
key quantitative results, or trends
- report those results which answer the
questions you were asking
- identify trends, relative change or differences,
- a brief summary of your interpetations
and conclusions. (from Discussion)
- clearly state the implications of the
answers your results gave you.
Title can only make the simplest statement
about the content of your article, the Abstract allows you to
elaborate more on each major aspect of the paper. The length
of your Abstract should be kept to about 200-300 words maximum
(a typical standard length for journals.) Limit your statements
concerning each segment of the paper (i.e. purpose, methods,
results, etc.) to two or three sentences, if possible. The Abstract
helps readers decide whether they want to read the rest of the
paper, or it may be the only part they can obtain via electronic
literature searches or in published abstracts. Therefore, enough
key information (e.g., summary results, observations, trends,
etc.) must be included to make the Abstract useful to someone
who may to reference your work.
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do you know when you have enough information in your Abstract? A simple rule-of-thumb is to imagine that you
are another researcher doing an study similar to the one you
are reporting. If your Abstract was the only part of the paper
you could access, would you be happy with the information presented
2. Style: The Abstract is ONLY text. Use the active voice
when possible, but much of it may require passive constructions.
Write your Abstract using concise, but complete, sentences, and
get to the point quickly. Use past tense. Maximum length
should be 200-300 words, usually in a single paragraph.
The Abstract SHOULD NOT contain:
- lengthy background information,
- references to other literature,
- elliptical (i.e., ending with ...) or
- abbreviations or terms that may be confusing
- any sort of illustration, figure, or
table, or references to them.
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3. Strategy: Although it
is the first section of your paper, the Abstract, by definition,
must be written last since it will summarize the paper. To begin
composing your Abstract, take whole sentences or key phrases
from each section and put them in a sequence which summarizes
the paper. Then set about revising or adding words to make it
all cohesive and clear. As you become more proficient you will
most likely compose the Abstract from scratch.
4. Check your work: Once you
have the completed abstract, check to make sure that the information
in the abstract completely agrees with what is written in the
paper. Confirm that all the information appearing the
abstract actually appears in the body of the paper.
1. Function: The function of the
Introduction is to:
- Establish the context of the work being
reported. This is accomplished by discussing the relevant
primary research literature (with
and summarizing our current understanding of the problem you
- State the purpose of the work in the form of the hypothesis, question,
or problem you investigated; and,
- Briefly explain your rationale
and approach and, whenever possible, the possible outcomes your
study can reveal.
Quite literally, the Introduction must
answer the questions, "What was I studying? Why
was it an important question? What did we know about it
before I did this study? How will this study advance our knowledge?"
2. Style: Use the
active voice as much as possible. Some use of first person is
okay, but do not overdo it.
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3. Structure: The
structure of the Introduction can be thought of as an inverted
triangle - the broadest part at the top representing the most
general information and focusing down to the specific problem
you studied. Organize the information to present the more general
aspects of the topic early in the Introduction, then narrow toward
the more specific topical information that provides context,
finally arriving at your statement of purpose and rationale.
A good way to get on track is to sketch out the Introduction
backwards; start with the specific purpose and then decide
what is the scientific context in which you are asking the question(s)
your study addresses. Once the scientific context is decided,
then you'll have a good sense of what level and type of general
information with which the Introduction should begin.
Here is the information should flow in
- Begin your Introduction by clearly
identifying the subject area of interest.
Do this by using key words from your Title
in the first few sentences of the Introduction to get it focused
directly on topic at the appropriate level. This insures that
you get to the primary subject matter quickly without losing
focus, or discussing information that is too general. For example,
in the mouse behavior paper, the words hormones and behavior
would likely appear within the first one or two sentences of
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- Establish the context by providing
a brief and balanced review of the pertinent published literature
that is available on the subject. The
key is to summarize (for the reader) what we knew about the specific
problem before you did your experiments or studies. This
is accomplished with a general review of the primary research
literature (with citations)
but should not include very specific, lengthy explanations that
you will probably discuss in greater detail later in the Discussion. The judgment of what is general
or specific is difficult at first, but with practice and reading
of the scientific literature you will develop e firmer sense
of your audience. In the mouse behavior paper, for example, you
would begin the Introduction at the level of mating behavior
in general, then quickly focus to mouse mating behaviors and
then hormonal regulation of behavior. Lead the reader to your
statement of purpose/hypothesis by focusing your literature review
from the more general context (the big picture e.g., hormonal
modulation of behaviors) to the more specific topic of interest
to you (e.g., role/effects of reproductive hormones, especially
estrogen, in modulating specific sexual behaviors of mice.)
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literature should you look for in your review of what we know
about the problem? Focus your
efforts on the primary research journals - the journals
that publish original research articles. Although you may read
some general background references (encyclopedias, textbooks,
lab manuals, style manuals, etc.) to get yourself acquainted
with the subject area, do not cite these, becasue they contain
information that is considered fundamental or "common"
knowledge wqithin the discipline. Cite, instead, articles that
reported specific results relevant to your study. Learn, as soon
as possible, how to find the primary literature (research
journals) and review articles rather than depending on
reference books. The articles listed in the Literature Cited
of relevant papers you find are a good starting point to move
backwards in a line of inquiry. Most academic libraries
support the Citation Index - an index which is useful
for tracking a line of inquiry forward in time. Some of
the newer search engines will actually send you alerts of new
papers that cite particular articles of interest to you. Review
articles are particularly useful because they summarize all
the research done on a narrow subject area over a brief period
of time (a year to a few years in most cases).
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- Be sure
to clearly state the purpose and /or hypothesis that you investigated. When you are first learning to write in this
format it is okay, and actually preferable, to use a pat statement
like, "The purpose of this study was to...." or "We
investigated three possible mechanisms to explain the ... (1)
blah, blah..(2) etc. It is most usual to place the statement
of purpose near the end of the Introduction, often as the topic
sentence of the final paragraph. It is not necessary (or even
desirable) to use the words "hypothesis" or "null
hypothesis", since these are usually implicit if you clearly
state your purpose and expectations.
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a clear statement of the rationale for your approach to the problem
studied. For example: State briefly
how you approached the problem (e.g., you studied oxidative respiration
pathways in isolated mitochondria of cauliflower). This will
usually follow your statement of purpose in the last paragraph
of the Introduction. Why did you choose this kind of experiment
or experimental design? What are the scientific merits
of this particular model system? What advantages does
it confer in answering the particular question(s) you are posing?
Do not discuss here the actual techniques or protocols
used in your study (this will be done in the Materials
and Methods); your readers will be quite familiar with the
usual techniques and approaches used in your field. If you are
using a novel (new, revolutionary, never used before)
technique or methodology, the merits of the new technique/method
versus the previously used methods should be presented
in the Introduction.
MATERIALS AND METHODS
This section is variously called Methods
or Methods and Materials.
In this section you explain clearly how you carried out
your study in the following general structure and
organization (details follow below):
- the the organism(s)
studied (plant, animal, human, etc.) and, when relevant,
their pre-experiment handling and care, and when and where the
study was carried out (only if location and time are important
factors); note that the term "subject" is used ONLY
for human studies.
- if you did a field study, provide a description
of the study site, including the significant physical
and biological features, and the precise location (latitude and
longitude, map, etc);
- the experimental
OR sampling design (i.e., how the experiment or study
was structured. For example, controls, treatments, what variable(s)
were measured, how many samples were collected, replication,
the final form of the data, etc.);
- the protocol for
collecting data, i.e., how the experimental procedures
were carried out, and,
- how the data
were analyzed (qualitative analyses and/or statistical procedures
used to determine significance, data transformations used, what
probability was used to decide significance, etc).
your presentation so your reader will understand the logical
flow of the experiment(s); subheadings work well for this
purpose. Each experiment or procedure should be presented as
a unit, even if it was broken up over time. The experimental
design and procedure are sometimes most efficiently presented
as an integrated unit, because otherwise it would be difficult
to split them up. In general, provide enough quantitative
detail (how much, how long, when, etc.) about your
experimental protocol such that other scientists could reproduce
your experiments. You should also indicate the statistical
procedures used to analyze your results, including the probability
level at which you determined significance (usually at 0.05 probability).
The style in this section should read as if you were verbally
describing the conduct of the experiment. You may use the active
voice to a certain extent, although this section requires more
use of third person, passive constructions than others. Avoid
use of the first person in this section. Remember to use the
past tense throughout - the work being reported is done,
and was performed in the past, not the future. The Methods section
is not a step-by-step, directive, protocol as you
might see in your lab manual.
for writing the Methods section.
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organism(s) used in the study.
This includes giving the (1) source (supplier or where
and how the orgranisms were collected), (2) typical
size (weight, length, etc), (3) how they were handled,
fed, and housed before the experiment, (4) how
they were handled, fed, and housed during the experiment.
In genetics studies include the strains or genetic stocks used.
For some studies, age may be an important factor. For example,
did you use mouse pups or adults? Seedlings or mature plants?
STUDIES ONLY: Describe the site
where your field study was conducted. The description must include both physical
and biological characteristics of the site pertinant to
the study aims. Include the date(s) of the study (e.g., 10-15
April 1994) and the exact location of the study area. Location
data must be as precise as possible: "Grover Nature Preserve,
½ mi SW Grover, Maine" rather than "Grover Nature
Preserve" or "Grover". When possible, give the
actual latitude and longitude position of the site: these can
be obtained using handheld GPS units, OR, from web resources
such as Google Earth(TM) and MapQuest(TM). It is often a good idea to include a map
(labeled as a Figure) showing the study location in relation
to some larger more recognizable geographic area. Someone else
should be able to go to the exact location of your study site
if they want to repeat or check your work, or just visit your
- NOTE: For laboratory
studies you need not report the date and location
of the study UNLESS it is necessary information for someone
to have who might wish to repeat your work or use the same facility.
Most often it is not. If you have performed experiments
at a particular location or lab because it is the only place
to do it, or one of a few, then you should note that in your
methods and identify the lab or facility.
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your experimental design clearly. Be
sure to include the hypotheses you tested, controls,
treatments, variables measured, how many replicates
you had, what you actually measured, what form the data
take, etc. Always identify treatments by the variable or treatment
name, NOT by an ambiguous, generic name or number (e.g., use
"2.5% NaCl" rather than "test 1".) When your
paper includes more than one experiment, use subheadings
to help organize your presentation by experiment. A general experimental
is available to help plan your
experiments in the core courses.
Describe the procedures for your study in sufficient
detail that other scientists could repeat your work to verify
your findings. Foremost in your
description should be the "quantitative" aspects of
your study - the masses, volumes, incubation times, concentrations,
etc., that another scientist needs in order to duplicate your
experiment. When using standard lab or field methods and instrumentation,
it is not always necessary to explain the procedures (e.g., serial
dilution) or equipment used (e.g., autopipetter) since other
scientists will likely be familiar with them already.
You may want to identify certain types
of equipment by vendor name and brand or category (e.g., ultracentrifuge
vs. prep centrifuge), particularly if they are not commonly found
in most labs. It is appropriate to report, parenthetically, the
source (vendor) and catalog number for reagents used, e.g., "....poly-L-lysine (Sigma #1309)." When using a method described in another
published source, you can save time and words by providing the
relevant citation to the
source. Always make sure to describe any modifications you have
made of a standard or published method.
Very frequently the experimental design and data collection procedures
for an experiment cannot be separated and must be integrated
together. If you find yourself repeating lots of information
about the experimental design when describing the data collection
procedure(s), likely you can combine them and be more concise.
Although tempting, DO NOT say that you "recorded the
data," i.e., in your lab notebook, in the Methods description.
Of course you did, because that is what all good scientists
do, and it is a given that you recorded your measurements
how the data were summarized and analyzed. Here
you will indicate what types of descriptive statistics were used
and which analyses (usually hypothesis tests) were employed to
answer each of the questions or hypotheses tested and determine
The information should include:
- Statistical software used: Sometimes it is necessary to report which statistical
software you used; this would be at the discretion of your instructor
or the journal;
- how the data were summarized (Means,
percent, etc) and how you are reporting measures of variability
(SD,SEM, 95% CI, etc)
- this lets you avoid having to repeatedly
indicate you are using mean ± SD or SEM.
- which data transformations were
used(e.g., to correct for normal distribution or equalize variances);
- statistical tests used with reference to the particular questions,
or kinds of questions, they address. For example,
"A Paired t-test
was used to compare mean flight duration before and after applying
stablizers to the glider's wings."
"One way ANOVA
was used to compare mean weight gain in weight-matched calves
fed the three different rations."
the three pH treatment groups for each variable were done using
one way ANOVA (with Tukey's post hoc test) or a Kruskal-Wallis
Test (with Dunn's post hoc test)."
- any other numerical (e.g., normalizing
data) or graphical techniques used to analyze
- what probability (a priori)
was used to decide significance;
usually reported as the Greek symbol alpha.
- NOTE: You DO NOT need to say that
you made graphs and tables.
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Here is some additional advice on particular
problems common to new scientific writers.
Problem: The Methods section is
prone to being wordy or overly detailed.
- Avoid repeatedly using a single sentence
to relate a single action; this
results in very lengthy, wordy passages. A related sequence of
actions can be combined into one sentence to improve clarity
Problematic Example: This is a very long and wordy description of
a common, simple procedure. It is characterized by single actions
per sentence and lots of unnecessary details.
"The petri dish
was placed on the turntable. The lid was then raised slightly.
An inoculating loop was used to transfer culture to the agar
surface. The turntable was rotated 90 degrees by hand. The loop
was moved lightly back and forth over the agar to spread the
culture. The bacteria were then incubated at 37 C for 24 hr."
Same actions, but all the important information is given in a
single, concise sentence. Note that superfluous detail and otherwise
obvious information has been deleted while important missing
information was added.
"Each plate was
placed on a turntable and streaked at opposing angles with fresh
overnight E. coli culture using an inoculating loop. The bacteria
were then incubated at 37 C for 24 hr."
the author assumes the reader has basic knowledge of microbiological
techniques and has deleted other superfluous information. The
two sentences have been combined because they are related actions.
"Each plate was
streaked with fresh overnight E. coli culture and incubated at
37 C for 24 hr."
Avoid using ambiguous terms to identify controls or treatments,
or other study parameters that require specific identifiers to
be clearly understood. Designators such as Tube 1, Tube 2, or
Site 1 and Site 2 are completely meaningless out of context and
difficult to follow in context.
Problematic example: In this example the reader will have no clue
as to what the various tubes represent without having to constantly
refer back to some previous point in the Methods.
"A Spec 20 was
used to measure A600
of Tubes 1,2, and
3 immediately after
chloroplasts were added (Time 0) and every 2 min. thereafter
until the DCIP was completely reduced. Tube 4's
A600 was measured only at Time 0 and
at the end of the experiment."
Improved example: Notice how the
substitution (in red) of treatment and control identifiers clarifies
the passage both in the context of the paper, and if taken out
"A Spec 20 was
used to measure A600 of the reaction mixtures exposed to light intensities
of 1500, 750, and 350 uE/m2/sec immediately after chloroplasts were added (Time
0) and every 2 min. thereafter until the DCIP was completely
reduced. The A600 of the no-light control was measured only at Time 0 and at the end of
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1. Function: The function of the
Results section is to objectively present your key results,
without interpretation, in an orderly and logical
sequence using both text and illustrative
materials (Tables and Figures). The results section always
begins with text, reporting the key results and referring to
your figures and tables as you proceed. Summaries
of the statistical analyses may appear either in the text
(usually parenthetically) or in the relevant Tables or Figures
(in the legend or as footnotes to the Table or Figure). The Results
section should be organized around
Tables and/or Figures that should
be sequenced to present your key findings in a logical order.
The text of the Results section should be crafted to follow this
sequence and highlight the evidence needed to answer the questions/hypotheses
you investigated. Important negative
results should be reported, too. Authors usually write the
text of the results section based upon the sequence of Tables
2. Style: Write the text of the
Results section concisely and objectively. The passive voice
will likely dominate here, but use the active voice as much as
possible. Use the past tense. Avoid repetitive paragraph
structures. Do not interpret the data here. The transition into
interpretive language can be a slippery slope. Consider the following
- This example highlights the trend/difference
that the author wants the reader to focus:
The duration of exposure
to running water had a pronounced effect on cumulative seed germination
percentages (Fig. 2). Seeds exposed to the 2-day treatment had
the highest cumulative germination (84%), 1.25 times that of
the 12-h or 5-day groups and 4 times that of controls.
- In contrast, this example
strays subtly into interpretation by referring to optimality
(a conceptual model) and tieing the observed result to that idea:
The results of the germination
experiment (Fig. 2) suggest that the optimal time for running-water
treatment is 2 days. This group showed the highest cumulative
germination (84%), with longer (5 d) or shorter (12 h) exposures
producing smaller gains in germination when compared to the control
for Writing the Results Section
asked questions (FAQs).
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Things to consider as you write your
What are the
"results"?: When you
pose a testable hypothesis that can be answered experimentally,
or ask a question that can be answered by collecting samples,
you accumulate observations about those organisms or phenomena.
Those observations are then analyzed to yield an answer to the
question. In general, the answer is the " key result".
The above statements apply regardless
of the complexity of the analysis you employ. So, in an introductory
course your analysis may consist of visual inspection of figures
and simple calculations of means and standard deviations; in
a later course you may be expected to apply and interpret a variety
of statistical tests. You instructor will tell you the level
of analysis that is expected.
For example, suppose you asked the question,
"Is the average
height of male students the same as female students in a pool
of randomly selected Biology majors?" You would first
collect height data from large random samples of male and female
students. You would then calculate the descriptive statistics
for those samples (mean, SD, n, range, etc) and plot these numbers.
In a course where statistical tests are not employed, you would
visually inspect these plots. Suppose you found that male Biology
majors are, on average, 12.5 cm taller than female majors; this
is the answer to the question.
- Notice that the outcome of a statistical
analysis is not a key result, but rather an analytical tool
that helps us understand what is our key result.
Differences, directionality, and magnitude: Report your results so as to provide as much
information as possible to the reader about the nature of differences
or relationships. For eaxmple, if you testing for differences
among groups, and you find a significant difference, it
is not sufficient to simply report that "groups
A and B were significantly different". How are they different?
How much are they different? It is much more informative to say
something like, "Group A individuals were 23% larger than
those in Group B", or, "Group B pups gained weight
at twice the rate of Group A pups." Report the direction
of differences (greater, larger, smaller, etc) and the magnitude
of differences (% difference, how many times, etc.) whenever
possible. See also below about use of the word "significant."
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the results section based on the sequence of Table and Figures
you'll include. Prepare the Tables and Figures as soon as all
the data are analyzed and arrange them in the sequence that best
presents your findings in a logical way. A good strategy is to
note, on a draft of each Table or Figure, the one or two key
results you want to addess in the text portion of the Results.
Simple rules to follow related to Tables and Figures:
- Tables and Figures are assigned
numbers separately and in the sequence that you will refer
to them from the text.
- The first Table you refer to is Table
1, the next Table 2 and so forth.
- Similarly, the first Figure is Figure
1, the next Figure 2, etc.
Table or Figure must include a brief description of the results
being presented and other necessary information in a legend.
- Table legends go above the Table; tables are read from top to bottom.
- Figure legends go below the figure; figures are usually viewed from bottom to top.
- When referring
to a Figure from the text, "Figure" is abbreviated
Fig. 1. Table is never abbreviated, e.g., Table 1.
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The body of the
Results section is a text-based presentation of the key findings
which includes references to each of the Tables and Figures.
The text should guide the reader
through your results stressing the key results which provide
the answers to the question(s) investigated. A major function
of the text is to provide clarifying information. You must refer
to each Table and/or Figure individually and in sequence (see
and clearly indicate for the reader the key results that each
conveys. Key results depend on your questions, they might include
obvious trends, important differences, similarities, correlations,
maximums, minimums, etc.
- Do not
reiterate each value from a Figure or Table - only the key result
or trends that each conveys.
- Do not
present the same data in both a Table and Figure - this is considered
redundant and a waste of space and energy. Decide which format
best shows the result and go with it.
- Do not
report raw data values when they can be summarized as means,
test summaries (test name, p-value) are usually reported
parenthetically in conjunction with the biological results they
support. Always report your results
with parenthetical reference to the statistical conclusion that
supports your finding (if statistical tests are being used in
your course). This parenthetical reference should include the
statistical test used and the level of significance (test statistic
and DF are optional). For example, if you found that the mean
height of male Biology majors was significantly larger than that
of female Biology majors, you might report this result (in blue)
and your statistical conclusion (shown in red) as follows:
"Males (180.5 ±
5.1 cm; n=34) averaged 12.5 cm taller than females (168 ±
7.6 cm; n=34) in the AY 1995 pool of Biology majors (two-sample t-test, t = 5.78,
33 d.f., p < 0.001)."
If the summary statistics
are shown in a figure, the sentence above need not report them
specifically, but must include a reference to the figure where
they may be seen:
"Males averaged 12.5
cm taller than females in the AY 1995 pool of Biology majors
t = 5.78, 33 d.f., p < 0.001; Fig.
Note that the report of
the key result (shown in blue) would be identical in a paper
written for a course in which statistical testing is not employed
- the section shown in red would simply not appear except reference
to the figure.
- Avoid devoting whole
sentences to report a statistical outcome alone.
- Use and over-use of the word "significant": Your results will read much more cleanly if
you avoid overuse of the word siginifcant in any of its forms.
- In scientific studies, the use of this
word implies that a statistical test was employed to make a decision
about the data; in this case the test indicated a larger difference
in mean heights than you would expect to get by chance alone.
Limit the use of the word "significant" to this purpose
- If your parenthetical statistical information
includes a p-value that indicates significance (usually when
p< 0.05), it is unncecssary (and redundant)
to use the word "significant" in the body of the sentence
(see example above) because we all interpret the p-value the
- Likewise, when you report that one group
mean is somehow different from another (larger, smaller, increased,
decreased, etc), it will be understood by your reader that you
have tested this and found the difference to be statisticallysignificant,
especially if you also report a p-value < 0.05.
results of your experiment(s) in a sequence that will logically
support (or provide evidence against) the hypothesis, or answer
the question, stated in the Introduction. For
example, in reporting a study of the effect of an experimental
diet on the skeletal mass of the rat, consider first giving the
data on skeletal mass for the rats fed the control diet
and then give the data for the rats fed the experimental
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negative results - they are important! If you did not get the anticipated results, it
may mean your hypothesis was incorrect and needs to be reformulated,
or perhaps you have stumbled onto something unexpected that warrants
further study. Moreover, the absence of an effect may
be very telling in many situations. In any case, your results
may be of importance to others even though they did not support
your hypothesis. Do not fall into the trap of thinking that results
contrary to what you expected are necessarily "bad data".
If you carried out the work well, they are simply your results
and need interpretation. Many important discoveries can be traced
to "bad data".
Always enter the appropriate units
when reporting data or summary statistics.
- for an individual value
you would write, "the
mean length was 10 m", or, "the maximum time was 140 min."
- When including a measure of variability,
place the unit after the error value, e.g., "...was 10 ± 2.3 m".
- Likewise place the unit after the last
in a series of numbers all having the same unit.
For example: "lengths
of 5, 10, 15, and 20 m", or "no differences were observed after
2, 4, 6, or 8 min. of incubation".
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| FAQs | style
| approach | use
of literature | results in discussion
The function of the Discussion is to interpret your results in
light of what was already known about
the subject of the investigation, and to explain our new understanding
of the problem after taking your results into consideration.
The Discussion will always connect to the Introduction
by way of the question(s) or hypotheses you posed and the literature
you cited, but it does not simply repeat or rearrange the Introduction.
Instead, it tells how your study has moved us forward from the
place you left us at the end of the Introduction.
Fundamental questions to answer here include:
- Do your results provide answers to your
testable hypotheses? If so, how do you interpret your findings?
- Do your findings agree with what others
have shown? If not, do they suggest an alternative explanation
or perhaps a unforseen design flaw in your experiment (or theirs?)
- Given your conclusions, what is our new
understanding of the problem you investigated and outlined in
- If warranted, what would be the next
step in your study, e.g., what experiments would you do next?
2. Style: Use the active voice whenever possible in this
section. Watch out for wordy phrases; be concise and make your
points clearly. Use of the first person is okay, but too much
use of the first person may actually distract the reader from
the main points.
Approach: Organize the Discussion
to address each of the experiments or studies for which you presented
results; discuss each in the same sequence as presented in the
Results, providing your interpretation of what they mean in the
larger context of the problem. Do not waste entire sentences
restating your results; if you need to remind the reader of the
result to be discussed, use "bridge sentences" that
relate the result to the interpretation:
"The slow response
of the lead-exposed neurons relative to controls suggests that...[interpretation]".
You will necessarily make reference
to the findings of others in order to support your interpretations.Use
subheadings, if need be, to help organize
your presentation. Be wary of mistaking the reiteration of a
result for an interpretation, and make sure that no
new results are presented here that rightly belong in the
relate your work to the findings of other studies - including
previous studies you may have done and those of other investigators.
As stated previously, you may
find crucial information in someone else's study that helps you
interpret your own data, or perhaps you will be able to reinterpret
others' findings in light of yours. In either case you should
discuss reasons for similarities and differences between yours
and others' findings. Consider how the results of other studies
may be combined with yours to derive a new or perhaps better
substantiated understanding of the problem. Be sure to state
the conclusions that can be drawn from your results in light
of these considerations. You may also choose to briefly mention
further studies you would do to clarify your working hypotheses.
Make sure to reference any outside
sources as shown in the Introduction section.
introduce new results in the Discussion. Although
you might occasionally include in this section tables and figures
which help explain something you are discussing, they must not
contain new data (from your study) that should have been presented
earlier. They might be flow diagrams, accumulation of data from
the literature, or something that shows how one type of data
leads to or correlates with another, etc. For example, if you
were studying a membrane-bound transport channel and you discovered
a new bit of information about its mechanism, you might present
a diagram showing how your findings helps to explain the channel's
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(include as needed) | FAQs |
If, in your experiment, you received any
significant help in thinking up, designing, or carrying out the
work, or received materials from someone who did you a favor
by supplying them, you must acknowledge their assistance and
the service or material provided. Authors always acknowledge
outside reviewers of their drafts (in PI courses, this
would be done only if an instructor or other individual
critiqued the draft prior to evaluation) and any sources of
funding that supported the research. Although usual style
requirements (e.g., 1st person, objectivity) are relaxed somewhat
here, Acknowledgments are always brief and never flowery.
- Place the Acknowledgments
between the Discussion and the Literature Cited.
The Literature Cited section gives an alphabetical listing (by
first author's last name) of the references that you actually
cited in the body of your paper. Instructions
for writing full citations for various sources are given
in on separate page. A complete format list for virtually all
types of publication may be found in Huth
Do not label this section "Bibliography". A bibliography contains references that you
may have read but have not specifically cited in the text. Bibliography
sections are found in books and other literary writing, but not
scientific journal-style papers.
and Instructions for standard full citations of sources.
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| Function | Headings
| Types of Content | Tables
Function: An Appendix contains information that is non-essential
to understanding of the paper, but may present information that
further clarifies a point without burdening the body of the presentation.
An appendix is an optional part of the paper, and is only
rarely found in published papers.
Headings: Each Appendix should be identified by a Roman
numeral in sequence, e.g., Appendix I, Appendix II, etc. Each
appendix should contain different material.
examples of material that might be put in an appendix (not an
- raw data
- maps (foldout type especially)
- extra photographs
- explanation of formulas, either already
known ones, or especially if you have "invented" some
statistical or other mathematical procedures for data analysis.
- specialized computer programs for a particular
- full generic names of chemicals or compounds
that you have referred to in somewhat abbreviated fashion or
by some common name in the text of your paper.
- diagrams of specialized apparati.
and Tables in Appendices
Figures and Tables are often found in
an appendix. These should be formatted as discussed previously
(see Tables and Figures), but
are numbered in a separate sequence from those found in the body
of the paper. So, the first Figure in the appendix would be Figure
1, the first Table would be Table 1, and so forth. In situations
when multiple appendices are used, the Table and Figure numbering
must indicate the appendix number as well (see Huth
and others, 1994).