How to prepare a good literature review with the help of free online tools

booksDr Mansoor Ali

A literature review is a systemic and thorough search of all types of related publications, that provides the raw materials for the research


  • This is a comprehensive study and interpretation of literature that address a specific topic – what is already known , gap in the existing research base, justify why new research required.
  • This is not a place to dump everything
  • Include matter related to Research only
  • Academic related matters only
  • No need of anatomy or physiology
  • Never copy and paste the entire lines or paragraph, but re-write the key finding in your own language – beware of plagiarism.

Example : “Fever is common in Kerala”
You have to rewrite in your own word to avoid plagiarism
“Kerala is a place where fever is common in rainy season” – then give reference.

Literature Search is required for 

  • Selection of topic
  • Planning dissertation and writing protocol
  • Continuing the research
  • Writing up the dissertation

Online Search
Nowadays literature review is so easy, there are many reliable online databases available.

1.PubMed Central
What kind of database is pubmed?
PubMed is a service of the US National Library of Medicine® that: Provides free access to MEDLINE®, the NLM® database of indexed citations and abstracts to medical, nursing, dental, veterinary, health care, and preclinical sciences journal articles. Includes additional selected life sciences journals not in MEDLINE.
That contains 3.7 million medical articles

How to search in Pubmed?
Never type the entire matter as we are searching in Google
Split your research question or topic
Example : What role does pain have in sleep disorders?
Type the key concepts are: Pain, Sleep disorders

Visit , click on “advanced search” button. If you want to get research papers on  Homeopathy in Diabetes Mellitus ( Spelling Homeopathy yield more results than homoeopathy).

Type Diabetes Mellitus in Title/Abstract section, then type Homeopathy in ‘MeSH or All fields or Text word section. Then click on Search button. You can save your previous search by selecting “Add to History” section.

Use Booleans like AND OR NOT for better results : That give more specific and reliable but limited results.







Remember to practice with filters available after on left side, default is ‘All fields”.

On clicking you will get hundreds of articles depending on the key words you used.  So to get more suitable papers use the filters available on the left side. Always select “Free full text” to get full papers.








Then click on Free Full Text button on Rt top of the page








Give you email ID on the “Sign to NCBI” on Rt top for better results.

Create an account

  • To store previous search
  • For getting email alerts on new article of your interest

Video tutorial on How to search in PubMed :

Cochrane Reviews
What is the Cochrane Database?
The Cochrane Library (ISSN 1465-1858) is a collection of six databases that contain different types of high-quality, independent evidence to inform healthcare decision-making, and a seventh database that provides information about Cochrane groups.

Visit :

Select “Advanced Search” – type your key words only








Utilise Filters on the left side for more precise results









Video tutorial on How to search in Cochrane Library :

National Medical Library India -ERMED
The National Medical Library aims to provide wide and efficient library and information services to the health science (HS) professionals in India. It functions under the administrative control of the Directorate General of Health Services.

The Library is mainly a reference library in the field of Medical and Allied Sciences. It is open for consultation to the entire Medical, Paramedical and Allied Professions.

It has 3.6 lakh volumes of books, reports, bound volume of journals and other literature and adds about 3000 latest books and serials every year. It also subscribes to 2000 current periodicals

IndMED – peer reviewed journal
IndMED – database covering prominent peer reviewed Indian biomedical journals. Database designed to provide medical professionals/researchers/students and the medical library professional quick and easy access to Indian literature.

Indian Medical Journals – full text
MedIND provides free full text articles published in select Indian Biomedical Journals indexed in IndMED or PubMed

Free Medical Journals
The Free Medical Journals Site was created to promote the free availability of full text medical journals on the Internet.

Google Scholar








Google Scholar is a freely accessible web search engine that indexes the full text or metadata of scholarly literature across an array of publishing formats and disciplines.










Citations/Referencing is also re very easy in Google Scholar

Ayush Research Portal
Evidence Based Research Data of AYUSH Systems at Global Level by Ministry of AYUSH.

Now we will discuss another important part – that add credibility to a dissertation


  1. Ananatha Krishnan N:medicaal postgraduate dissertation a step by step approach.India:Wolters Kluwer;2013
  2. Munir Ahammed R : Research Methodology.Bangalore: Centre for Homeopathic Studies;2005
  3. Writing a reference list in the Vancouver style:VIKO; [Published 29.04.2011;Cited on 30-04-2016].Available from
  4. PubMed Central : National Center for Biotechnology Information, U.S. National Library of Medicine ; [cited on 29.04.2016]. Available from
  5. Cochrane Libray : Wiley Online Library;[cited on 29.04.2016]. Available from

Dr Mansoor Ali K R BHMS,MD(Hom)
Associate  Professor- Govt. Homeopathic Medical College, Calicut
Email :