The essential difference between abstract and introduction is that the abstract is a short summary of your entire study in this order: The objective of study, methods, results and conclusion. It shows the high points of your study plus a very brief background information.
The introduction, on the other hand contains only some elements of the abstract. Therefore, you should expand the reasons that made you ask the specific research questions.
What is a research paper abstract?
The abstract summarizes your work and attract reader’s attention with the most important points about your study. Often, this part should not exceed 250 words.
The content of the abstract
First of all, you provide the background and objectives of your study in a paragraph. Then you provide important details about the study plan, the number of participants, treatment or intervention, controls, etc. Finally, you will provide the most important results of your study. The language in the abstract section should be very clear even to the none-professionals.
The Introduction of a research paper
The introduction of a research paper informs the readers about the study background. It makes it clear for the reader why you are conducting this study. Most journals ask for a brief introduction (500 words or fewer). Whether or not the journals ask you for limited introduction, you should make it as brief as possible.
Your introduction indicates to the reader what has led you to your main study questions. It does not need to provide all details or cite every study in the field. The introduction should start with a general statement and then narrow it down to your specific research question.
- Abstract include results while introduction almost never include results. At maximum, depending on the journal, you can generalize your findings in a sentence.
- Abstract will provide a conclusion while introduction will almost never reveal any of the study findings to the reader.
- The abstract provides details about the methods and study design, while the introduction provides very brief information, such as “Here, using mice” or “In this study of patients with breast cancer.” Details such as numerical values will be kept for Material and Methods section.
- The abstract offers a brief background section, consisting of one or two sentences at most. The introduction, on the other hand, reveals the background succinctly but more expansively by providing the context for why you have asked the research questions and the chain of the evidence that has led to the study you conducted.
- The language in the abstract will be more accessible to general readers and non-professionals. Therefore, it is better not to use jargon and abbreviations as much as possible. The introduction, in contrast, contains more details of interest to specialists and you are allowed to use abbreviations if required.
- An abstract does not contain reference citations while an introduction does.
- An abstract usually contains 250 words or fewer, on the other hand, the word limitation of introduction is fewer than 500 in most journals, though in some journals the introduction can contain more than 500 words.
Some high profile journals have submission options that allow for the abstract to be used as the paper introduction. These submission categories are usually called “Letters” or “Short submissions.” In such cases, the abstract plays the role of the introduction to the article and will be provided as a fully referenced paragraph that both introduces the study and summarizes its results and design.