Session 2: literature sEaRching

1. Introduction to Research Methods Session 2: literature sEaRching

2. Why do a literature search? • Establish what is already known in your area of interest • Numbers of previous studies • Findings: positive and negative • Context – where and when published? • Methodology used and its limitations Is there a gap in the literature? New areas to explore? Controversies in the field?

3. Key Steps • Defining TERMS or KEY WORDS • Selecting combinations of terms • Specifying Database • Limiting your search

4. Defining terms or key words • Population • Intervention • Comparison • Outcome What are all the possible combination of terms that could be used to describe what you want to find out?

5. Key Words A way of searching for words and phrases that appear in certain fields in the database (eg title, abstract) so you can identify relevant articles to review

6. KEY TERMS community based interventions for postnatal depression POPULATION: Women INTERVENTION: community based interventions COMPARISON: Depression OUTCOME: Recovery

7. Exercise Defined your own PICO table for your research area

8. Generating key words • From your original research question, then generate as many associated/ alternative words • Look at the literature if you are not sure, to see what other terminology is used

9. Obtaining your search terms

10. Using AND and OR (Boolean Logic) Puts your research question in a way a computer will understand Three key words: AND, OR, NOT OR: expands your search AND: narrows your search NOT: excludes topics

11. Exercise • Referring to the handout, Develop your own lists of OR and AND words for your search

12. Using Free Text Words Other techniques to ensure you capture the right articles: Truncation = * symbol Allows you to search for all different forms of a word at one time. Good for plurals E.g. nurse OR nurses OR nursing can be changed to nurs*

13. Truncation Key is to place it after the shared root of your words = the group of letters that ALL forms of the word have in common Therapi* = only therapies or therapist Therap* = all shared roots Be careful not to place it TOO FAR back Ther* = therapy, thermometer, there Try this for your search terms

14. ADJACENCY (ADJ) • Allows you to specify words that need to be found near each other, but can be in any order • Allows you to search for different phrases at same time • Works on the principle that words near each other are likely to be related Asthma ADJ inhaler = asthma inhaler or inhaler asthma Try this for your search terms

15. Adjacency.. You can specify HOW CLOSE the words should be: E.g within 3 words Asthma ADJ3 inhaler = an inhaler for asthma, an asthma inhaler, using an inhaler for moderate asthma Try this for your search terms

16. Using Truncation & Adjacency • Try combining them together e.g. asthm* ADJ inhaler* Gives you even more flexibility

17. Using a wildcard symbol (?) • Wildcard symbol (?) – stands for a possible letter. • Useful if searching where there are different spellings e.g USA vs UK e.gcolo?r = colour OR color Must have at least 2 LETTERS before it (can’t use it for foetal- f?tal)

18. Putting it all together in a search string For example – “Lung cancer” turned into a search string: (lung* OR pulmonary) adj3 (tumo?r* OR neoplasm* OR neoplasm* or malignan* OR cancer*) Use of brackets to show that one of the terms inside the first set of brackets should be adjacent to one of the terms in the second set of brackets

19. Exercise • Put all your key words together into a search string

20. Using Subject or MeSH headings • Most databases index individual articles into a number of subject headings, which describe their content. • Differ between databases Eg an article might be indexed under 15 subject headings, with some identified as the main subject

21. Subject Headings • Are organised into a subject tree: going from general to more specific

22. Subject headings Advantages: • More relevant articles • More likely to get all instances But often requires a combination of subject headings S

23. Limiting your search You may have too many results!! Limits help you weed out irrelevant articles.

24. Common Limits • Years of publication • Language: English Language • Abstract/ Full text availability • Human/Animal studies Additional limits: • Publication Type of article: Review, case report • Journal Subsets • Age groups

25. Literature searches What to do with your findings: • Review the abstracts/titles for relevance • Create a group of articles you wish to save/ export • SAVE or EXPORT them to your reference manager, email or print them! Exact way this is done varies between databases

26. Reference Managers • Allows you to keep Titles, Abstracts and Full text of articles in a specific reference manager system • Enables you to cite these articles easily as you write your paper up • If used well, avoids quite a lot of time and confusion!

27. Examples of reference managers • End Note Web • Reference Manager • Word also has its own reference manager

28. PRACTICAL SESSION: • Using HINARI: http://hinari-gw.who.int/ Username: mal001 Password: 68711A • OVID (MedLine) www.knowledge.scot.nhs.uk Username: efssgleadowware001 Password: tomato1

29. Homework Undertake a literature search in the research area you will focus on for your research project Read the abstracts and narrow it to 10 relevant articles. Identify which ones you can access the full text for and find these