HOW TO WRITE THE PERFECT CONCLUSION
The conclusion section of your manuscript is far more important than its brevity suggests. The conclusion (or the last part of your discussion for submissions that do not need an extra conclusion) is vital for the success of your manuscript. This short text will explain the purpose, the structure, and the required contents of the conclusion. This is a step-by-step guide to write the perfect conclusion.
The purpose of the conclusion section
Some journals require a separate section for the conclusion and some journals call this part a “summary”. For some journals, a separate conclusion is not required at all, in which case, a short paragraph with the same information needs to be included as the last part of the discussion. Whatever this section is called, it is always the last passage of your manuscript and because of this, it is about as important for your paper as the abstract. The last thing your readers will see of your study should be something that lets them remember your work and that carries a strong message to your readers. Just as the purpose of the abstract is to generate lasting interest in your study, the purpose of the conclusion is to close your manuscript and make it memorable for your readers. The conclusion is likely what will stay in their mind longest, together with the title and some of your figures. Without a clear and meaningful conclusion, your reviewers will find it difficult to judge whether your work is good enough for publication in your journal of choice and if in doubt, they generally tend to advise rejection.
In your conclusion, write what your findings really mean for your readers and for your field in general. This section needs to be written with an interesting tone and content. That way, it will be memorable for your readers.
There is no need to make your conclusion any longer than necessary. For most conclusions, this means that a short paragraph of just a few sentences will be sufficient. The length will be about the same as your abstract, maybe even shorter, depending on the length of your abstract. The main body of your text should already contain everything that is needed to understand these final sentences. Remember, the conclusion should provide a good and memorable finish of the story you are telling with your manuscript – so there is no need for lengthy content. Resist the temptation to repeat any material from the other sections just to make it longer. If you can write a good and sufficient conclusion with three sentences, this is a very good thing and making it longer will likely make it worse.
The content and structure of your conclusion
When you write your conclusion, you will already have a manuscript with a well-structured and interesting introduction and an effective and strong abstract by the time you start writing your conclusion. As explained above, your conclusion section should not repeat any of the content of either the introduction or abstract. In particular, never restate here what you have done in your study, or what your paper tries to achieve. Instead, you should focus this section on what you have found and, most importantly, what your findings mean. Listing experimental results or restating your findings is also not needed here.
The conclusion shows how your work advances your field from the present state of knowledge – before your manuscript, to where your field is now after your study. The main thing you need to include is a clear scientific justification for your particular study. This is the place to write why your study and the results you found are meaningful and why the scientific community cannot live without them. Indicate uses of your research and let your readers know how your findings extend your field. If this is meaningful for your manuscript, you can split this section into global and more specific conclusions, thus showing your study in both a global context and a more specific, field-related context. Of course, always keep in mind that what you are writing needs to be related to the objectives that you wrote about in your introduction.
If you haven’t done so already in your discussion, you can suggest future experiments that are now possible in light of your findings. Here, think of what could or should still be done in relation to the issues you addressed in your paper. Where do you think your field still lacks specific understanding and how could this be changed? For this, it is especially important to point out which of these future ideas are already being pursued. You might either know of a colleague who currently works on a specific experiment or plans to do so in future. In this case, you could mention his or her name and state that they are working on pursuing this specific idea. If you plan to do this, make sure to check with these scientists before mentioning their name and writing about their studies. Only do so with the specific permission of these scientists – never without it.
If you plan to conduct a specific experiment next and would like to mention that in your conclusion, use words such as “in the next experiment, we will work on X” or “we are currently addressing this question in our laboratory”. This will ensure that every reader understands that you are already working on this. If you would like to provide your ideas for future experiments as a general invitation to your readers, maybe because you cannot pursue the idea yourself, use wording such as “one remaining question is”, or “this question remains to be solved” after presenting it. That way, your readers will know that this could be their next project if they are interested. A sentence like this could even lead to an invitation to collaborate with a fellow researcher, who would like to start working together on that very question.