Previously we looked at the different types of scientific articles – what are they, what are the differences and what can you expect from each type. In this article, we are going to talk about the different parts of a scientific manuscript, what each part has (or should have) and what you can expect:
Parts of a Scientific Manuscript
If you remember from the previous article, there are many parts of a scientific article. Most of them have several parts in common, for example short communications and original research articles.
The parts we are going to look at are the Title, Abstract, Introduction, Materials + Methods, Results, Discussions, Conclusions, Acknowledgements (optional), Citations/References, and Appendices (as necessary). Most articles have many of these parts. One exception is review articles, which are organised by theme rather than by these sections. We will not be looking at these themed sections because they are unique to each article. Rather we will focus on the above list, which many types of manuscripts have in common.
One more note before we begin: the Results, Discussion and Conclusion sections vary from field to field. Sometimes they are all separate or sometimes one or more are combined. The social sciences (e.g. sociology and related fields) usually do not split up these fields because they can’t. The natural sciences (chemistry, physics and sometimes biology) usually have separate sections. Refer to the journal style guide for what they accept.
Let’s jump into the parts of a scientific manuscript!
What is a title? What does it need?
A title’s job is to describe in a few words (up to a mini-sentence) the contents of the paper. It often has a lot of keywords. These keywords often include things like what molecule was studied, which organism(s) was/were used/studied, the treatment, location of a field site, a response measured and so many more.
The title serves to capture the initial attention of the reader. They can be serious titles like “Pathways of heme utilization in fungi” to something more fun, such as “Fantastic yeasts and where to find them: the hidden diversity of dimorphic fungal pathogens”.
Whatever the title is, it should jump out at a reader and stand out in a list of many titles. The title is like a business post on social media, it needs to be able to stand alone but tell the reader more about what they can expect from your “brand” – the science that you do.
Something that titles should be are short and unambiguous (as much as possible). A good title tells the reader exactly what they need to know and why they should read your paper. It should also do it in as few words as possible. While a funny title is not necessarily short, it should capture a reader’s attention.
What is an introduction? What does it do and what does it need to be an introduction?
An introduction is always the first main section of a manuscript. As such it is like a diplomat or the host/hostess at a party. It should welcome you, give you some basic information about what to do and what to expect, and lead you to where you need to be. The introduction of a scientific article does the same thing. It establishes the content, talks about the current understanding or state of the problem/question you research(ed), and/or states the purpose of the research.
A good introduction generally answers these questions:
- What was the author studying?
- Why was it important to study?
- What was known about the field before this study?
- How will this study help the field/advance knowledge?
In addition to these questions, there are a couple of more things you can expect. The introduction is usually written in the Active Voice. You will probably information on past research on this subject (e.g. Boven et al. researched XYZ) as well as the current state, so we also expect the present and past tenses (but not the future tenses).
We also expect to see the introduction start more broadly and then become more focused towards the end of the introduction. This will be discussed in more detail in a future post.
Materials and methods
The next section is the materials and methods section. What is it, what does it need and what does it do?
The materials and methods section has one function: to explain how the author did their research. There is only one way that an author can do that: clearly and concisely. The purpose is so that other scientists can recreate the experiments the author did. Because of that, it should be extremely easy to follow.
The materials and methods section usually is split into subsections. Generally each subsection should be for a different experiment or different process in one experiment. This could be about the organisms studied (e.g. handling and care), when and where the experiments took place (if important, such as field studies), experimental design, sampling design, the protocol for collecting data, how data was analysed, etc.
Materials and methods sections are always written like a verbal description of performing the experiment. The active voice is ok here but usually, the passive voice is used because of the nature of this section. Scientists focus here on what was done, not who did it (since that should not matter). Speaking of what was done, the past tense is always used. Everything here has been completed. Therefore everything is in the past.
Quick note: the materials and methods is not written like a step-by-step protocol. “First, add X amount of Chemical A to reaction vessel V” – this is a step-by-step protocol. Rather it is written as “First we added X amount of chemical A to reaction vessel V” (some active voice is ok) or “First X amount of chemical A was added to reaction vessel V”.
What is the results section? What does it need and what does it do?
The results section has one function: to present results WITHOUT interpretation. Often it uses figures and tables to show these results. As the famous saying goes: a picture is worth 1,000 words.
The results section should be organised around the results themselves and presented in a logical order. Often this is in the same order as the experiments that were discussed in the Materials and Methods section. Because the results are in a specific order, the figures/tables should be as well. The first one is Figure 1, the second one is Figure 2, etc.
The style for the results is concise and objective. Passive voice is used a lot here but the active voice should be used wherever possible. This is because the active voice is shorter and therefore more concise.
The results section also usually answers the following questions:
- What are you researching and what are the results?
- What are the differences, directionality and magnitude of all important information?
There is usually also a text-based organisation of key findings in addition to the figures. The text also picks out key information from the figures and uses it to talk about trends and key results (i.e. the ones that answer the research question(s)).
The longest part of a scientific manuscript – the Discussion
The function of the discussion section is to interpret the results. This includes using what was already known (old knowledge) and showing how the new understanding (new knowledge) fits with it. Because of this, it relates very closely to the results section. This is also why often they are combined into one section.
It also connects closely with the introduction section. The research questions that appeared in the introduction (might) now have answers. The discussion section is where those answers are.
Some of the other questions that are answered are:
- Do the results provide answers to the testable hypotheses? If so, how do the authors interpret the data?
- Do the findings agree with what others found? If not, do they suggest an alternative explanation or perhaps an unforeseen design flaw in the experiment?
The conclusion section is usually the shortest in any scientific article. The conclusion is usually one paragraph or two at most. It summarises the main/major finding(s) of the article. It should also answer the following questions:
- Given the conclusions, what is the new understanding of the field?
- What is the next step in the study? What is next?
Because this is closely related to the discussion section, these sections often do not appear separately. Instead, the conclusion is the last paragraph or two of the discussion.
Usually, after the main sections of the article have finished (all the ones above), there is a section where the authors can thank everyone that helped them. How do they know who to thank? What are the criteria for including a person or organisation here? The answer is that these people or institutions helped in a significant way without being (or becoming) an author. For example, this could be a person or organisation that provided funding. It could also be someone who designed or carried out experiments (including lab techs if their contribution was significant). This can also include partner institutions/organisations/collaborations/groups that provided materials but did not receive any payment for them.
As you can see, many people and organisations might be part of this section. We will look at this in more detail on the topic of ethics.
After acknowledgements comes the section that lists all the supporting documents used in the article. There are two main styles:
For an alphabetical listing, the citations are listed by the first author’s last name. From there the articles appear in order from A to Z. In the paper, citations appear as the authors’ last name(s) and the year of publication. For example, it may be “(Brewers et al., 2022)”. The exact style varies widely but it is always listed in the style guide of the journal.
Rather than ordering the papers by name, the citations appear in the order they appear in the main text. For example, if “Brewers et al.” is first and “Allen et al.” is second in the list, then the citation for “Brewers” appears first and “Allen” appears second. Generally, the citation is just a number, such as “Elephants think humans are cute ”.
At this point, everything is said and done. Or is it? What happens if you have extra information? The answer is appendices.
Appendices (if allowed by the journal) are where you can put information that is relevant to the paper but not essential to understand it. If it were essential, it would be included in the main body of the paper. This information usually clarifies a point to give more information about the experimental background.
In some fields, such as computer science, appendices are common. In others, it is very rare.
Appendices usually use Roman Numerals for each appendix (e.g. Appendix I, Appendix II, etc).
Some examples of information you may find in appendices include raw data, maps, extra photos, explanation of formulas, specialized computer programs/source code, and extra diagrams/figures/tables.
The final part of a Scientific Manuscript
All done! Actually not quite yet. We forgot a small but extremely important part: the abstract!
An abstract has another name – the summary. An abstract summarises the major aspects of a paper. Usually, it does that by giving information about:
- The question investigated
- The purpose often appears in the first or second sentence
- Experimental design and methods used or the basic design of the study
- Major findings with key quantitative results or trends observed
- Brief info on the discussion of results/conclusions
Usually abstracts are between 200 and 300 words, although that depends on the journal. They also come in a couple of different designs. Many abstracts are just a chunk of text whereas others (especially in medicine) are split into separate parts. A further type, graphical abstracts, is one of the two previous types along with a picture that summarises the article. Here is an example:
There are certain things that abstracts do not include. They never use an acronym or abbreviation without defining them. They also do not go into much in-depth background information (that would be too long). You will only find full, complete sentences in an abstract- Finally, they also do not reference other literature. The reason for all of this is usually because of the word limit.
Want to learn more about Scientific English? You can find some more articles here. You may also be interested in Can I trust this scientific article? Is this a predatory journal?