What a conclusion is for
It closes the argument the introduction opened. The two should read as a pair.
What goes in, what stays out
A conclusion is short because most of its content already exists in the paper. Its work is selection and emphasis.
| Include | Leave out |
|---|---|
| A direct answer to the research question | A summary of each section |
| The main contribution, in a sentence | New data, analyses or citations |
| Implications for practice, policy or theory | Claims stronger than the discussion made |
| The most important limitation, briefly | A full list of limitations |
| A specific next step for research | "More research is needed" with no detail |
Conclusion or discussion?
The discussion interprets the results in detail and sets them against other studies. The conclusion steps back and says what the paper established. Some journals merge them, in which case the conclusion is the final paragraph of the discussion.
If your journal has a separate Conclusions heading, keep it to one or two paragraphs.
How long
For a journal article, a paragraph or two is usual. For an essay, around a tenth of the word count is a common guide. A thesis conclusion is a chapter: it revisits each research question, draws the findings together, and sets out contributions, limitations and future work.
The last sentence
End on the contribution or its consequence, stated plainly. Avoid closing on a limitation, an apology or a quotation. You don't need to begin with "In conclusion"; the heading already says so.