Writing up your manuscript is actually, storytelling!
Firstly, you set the stage, lighting, colors, and music in the INTRODUCTION, introducing the idea and establishing a background for the reader through literature review. Then, you tell the story of what you have done during your investigation journey in the MATERIALS AND METHODS and then the consequences of your actions in the RESULTS. You explain why you have chosen to do what you have done, the obstacles you faced, and compare your story to others in the DISCUSSION. And finally, you conclude with the moral of the story and your recommendations to others in the CONCLUSIONS.
The INTRODUCTION mainly consists of the literature review, the aim of the study and a justification for conducting the study. In this article, we are concerned about literature review and how to properly do it. Note that each sentence in the introduction must be referenced except the aim and justification and few sentences that you wrote yourself for the purpose of elaboration.
Your review of the literature serves the cause of familiarizing yourself with the topic you are researching, so you become a better researcher in the field as well as helping you write your literature review in the INTRODUCTION, and later in the DISCUSSION.
You start with setting the stage by introducing the main idea of your research and briefing the reader on what has been done by other researchers. Then, you do the lighting by shedding light on pieces of information you want the reader to understand. You chose and apply your color palette by detailing the main ideas in your study. Then you play the start music by stating the aim and justification of your research.
Briefing and setting the background in light of other researchers work is not an easy task. It involves a great deal of searching and it is time consuming. To make it easier for yourself, make a list of the keywords related to your topic so you can easily search them in the search engine of your choice. In healthcare and biomedical sciences, I personally like to use PubMed.com as it has good criteria for listing and it offers great tools for researchers. Another good resource for searching is Google Scholar.
In PubMed.com, I use the MeSH database which stands for Medical Subject Headings. It is a database that sets standard vocabulary in indexing so it becomes easier for you to find what you are looking for. For example, if you are searching for a “ache” as your keyword, you might not get what you’re looking for in the search results; but if you look up “ache” in the MeSH database, you’ll see that it’s standard term is “pain“. So if you search “pain” as your keyword, you’ll most likely find what interests you. MeSH database can get more complex by using boolean operators which are words that makes your search more specific and makes it more likely to find the articles you need for your write up. Boolean operators simply consist of the words (AND, OR, and NOT). You can read more on MeSh here.
Here is an example of literature review:
“Halitosis is a problem that has been reported to be a cause of embarrassment among individuals, and it has been reported that Americans spend up to 3 billion dollars a year on gum, mints and breath fresheners.¹ It has been reported that halitosis decreases self-confidence and leads to insecure social relations, to the extent of avoiding social interactions.²”
- Lee SS, Zhang W, Li Y. Halitosis update: A review of causes, diagnoses, and treatments. J Calif Dent Assoc 2007;35:258-60, 62, 64.
- McKeown L. Social relations and breath odour. Int J Dent Hyg 2003;1:213-7.
When writing, you must paraphrase i.e. you cannot copy and paste from others whatsoever! If you do so in very few circumstances, you must place quoted text between quotation marks. Paraphrasing is tricky in the beginning but you get used to it the more you practice it.
One last tip!
I usually make a table with four columns, the first column for author or authors names, the second for the year of the publication, the third for the original text I copied from the article, and finally the fourth column where I write the paraphrased sentence. Doing so helps me go back to the original text easily without having to wast time reading the article again. You may also add a column for the link, DOI or PMID!
For more on study design, please read this linked article (in Arabic).