Strategies for Answering Research QuestionsIntroduction to Health InformaticsApril 8, 2010

Robin Featherstone, BA, MLISClinical Medicine LibrarianAllyn & Betty Taylor Libraryrfeathe@uwo.ca

Presentation available at: http://www.slideshare.net/featherr

Objectives

• To provide an overview of the steps involved with conducting a research literature review

• To familiarize you with a variety of medical databases

Level of Evidence Pyramid

Qualitative Studies

Trip searches both

What’s a Research Lit Review?

A research literature review is a systematic, explicit and reproducible method for identifying, evaluating, and synthesizing the existing body of

completed and recorded work produced by researchers, scholars, and practitioners.*

*Fink, A. (2005). Conducting Research Literature Reviews. London: Sage.

7 tasks in the Research Lit Review

1. Selecting research questions2. Selecting your sources3. Choosing search terms4. Running your search5. Applying practical screening criteria6. Applying methodological screening criteria7. Synthesizing the results

Selecting research questions

Scenario

You’re applying for a grant to support your research on high blood pressure in patients with diabetes.

In pairs, discuss some possible research questions related to this topic.

Note: this is just a suggested topic; please feel free to discuss another topic of interest to you.

How questions influence search results

Relevancy

Retrieval(# of search results)

Broad Questions

Narrow Questions

High = lots of articles

Low = very few articles

High = directly relevant articles

Low = mostly irrelevant articles

Exercise

Select an appropriately narrow question for your research lit review and write it on your concept map.

Example: Does ambulatory BP readings improve detection rates for high blood pressure in patients with type 1 diabetes?

Selecting your sources

Lit reviews depend on data from seven sources

1. Online public bibliographic databases (i.e., MEDLINE)

2. Private bibliographic databases (i.e., EMBASE)3. Specialized bibliographic databases (i.e.,

Cochrane Database of Systematic Reviews)4. Manual or “hand searches” of references lists5. “Grey literature” (i.e., conference proceedings)6. Web reports7. Experts

Exercise

Select a source from Ovid for your first search & indicate your choice on your concept map

•Ovid MEDLINE•Ovid EMBASE•Ovid AMED

If searching EMBASE or AMED, please use the link on Taylor Med Info

User name: uwotrainingPassword: training

Why do I have to select a database first?

Your database will determine:– Your subject headings– Your operators (i.e., truncation symbols)

Different databases have different subject headings

• Tips:– Complete a concept map for each database that you search– Select subject headings that are the closest match for your concept– Pay attention to “explode” commands – some databases will search

related headings by default, others will not

Database Subject Headings

Medline MeSH

EMBASE EMTREE

CINAHL CINAHL Headings

Cochrane Library MeSH

Web of Science N/A

Scopus N/A

AMED AMED Subject Headings

Choosing search terms

Breaking down your question

1. Break you question into concepts2. Identify subject headings for each concept3. Identify keywords for each concept

Exercise: Identify ConceptsIdentify concepts for your research question. Write each concept at the top of the columns on your concept map

Example:

Research question: Does ambulatory BP readings improve detection rates for high blood pressure in patients with type 1 diabetes?

Concepts: #1: High Blood Pressure #2: Type 1 Diabetes #3: Ambulatory BP

Readings

Exercise: Identify Subject Headings

Search your database to find subject headings and enter them in the rows below your concepts

Concepts: #1: High Blood Pressure #2: Type 1 Diabetes #3: Ambulatory BP Readings

Subject Heading: Hypertension Diabetes Mellitus, Type 1 + Blood Pressure Monitoring, Ambulatory

Subject Heading: Hypertension, Malignant

+ = explode

Exercise: Identify keywords

• Think of synonyms for your concepts. These will be words that appear in the title or abstract fields. Tip: use a “target article” to help identify keywords

Concepts: #1: High Blood Pressure #2: Type 1 Diabetes #3: Ambulatory BP Readings

Subject Heading: Hypertension Diabetes Mellitus, Type 1 + Blood Pressure Monitoring, Ambulatory

Subject Heading: Hypertension, Malignant

Keyword: ((high OR elevated) ADJ ( blood pressure OR bp).tw.

((type 1 OR insulin?dependent OR juvenile?onset OR sudden?onset) AND diabet$).tw.

((ambulatory OR self OR home) AND monitor$ AND blood pressure).tw.

Keyword: hypertensi$.tw. IDDM.tw.

Some key operators in OvidOperator Command

$ Truncation (finds alternate endings)

? Wildcard (finds alternate spellings)

.tw. Text Word (tells Ovid to search for your term in the Title or Abstract fields)

() Parentheses control the order of search operations

Adj Adjacency operator (can be followed by a number) tells Ovid terms must appear adjacent to one another

AND all terms must appear in results

OR any terms will appear in results

Note: These are recommended operators for research lit reviews. There are many, many more operators... Use Ovid‘s Help menu to locate them.

Running your search

Running your search(es)• Start with your first concept

– Search for the subject headings first– Then search keywords– Combine these synonymous searches with OR using

your search history

• Repeat for your second, third, and subsequent concepts

• Finally, combine large search results set with AND

Running your search(es)

Search #2 =

Search #3 =

Search #4 =

Search #5 = #1 OR #2 OR #3 OR #4

Search #1 =

Concept 1

Search #6 =

Search #7 =

Search #8 =

Search #9 =

Concept 2

Search #10 = #6 OR #7 OR #8 OR #9

Search #11 = #5 AND #10

Results

Evaluate your results

• Too many citations? – Adjust your search strategy by adding another

concept or selecting a more narrow concept– Reduce the number of search terms

• Too few?– Adjust your search strategy by removing a concept– Add more search terms

• Irrelevant citations? – Remove broad terms

Applying practical & methodological screening criteria

Screening

• Two kinds: practical and methodological • Why?

– Use practical screening to identify a broad range of potentially useful studies

– Use methodological screening to identify the best available studies

Practical Screening Criteria – some examples

1. Date of publication – only studies conducted between 2005 and 2010

2. Participants or subjects – only children 6 to 12 years of age

3. Publication language – only materials written in English

4. Research design – only clinical trials

Exercise: Practical Screens

Use limits to apply some practical screens to your combined search result set

Apply by using “limits” (may also be called “search options”)

Methodological Screening Criteria - some questions to ask

• Is the study’s research design internally & externally valid?

• Are the data sources used in the study reliable & valid?

• Are the analytic methods appropriate? • Are the results meaningful in practical &

statistical terms?* *Fink, A. (2005). Conducting Research Literature Reviews. London: Sage.

Next steps

Saving and Managing Results

• Save your search history – Create an account with Ovid, Ebsco, etc..

• Export results to a citation manager (EndNote, RefWorkds, etc...) – Remove duplicates using the citation manager– Share with your research team– Apply methodological screens– Evaluate results and exclude studies which don’t

meet your criteria

Moving to another source

• Retain as much of your original strategy as possible

• Recognize that subject headings and operators* will be different (or non-existent)

• Keep track of your search terms using a new concept map

* Check help menus for lists of operators

Exercise

• Please complete the same search in one or more of the following databases:

1. MEDLINE (Ovid)2. EMBASE (Ovid)3. Cochrane Library (Wiley)4. CINAHL (Ebsco)5. SCOPUS (Elsevier)6. Web of Science (ISI)7. PsycINFO (CSA)8. AMED (Ovid)

Hand searching and final steps

• Locate the reference lists for selected articles*• Identify new articles that have cited your

articles*• Identify key journals and “hand search” their

issues - http://www.journaltocs.hw.ac.uk/ • Test your search strategy by checking to see if a

few “target articles” appear in the results

* Use Web of Science or Scopus

Synthesizing the results

Tip: Use a synthesis matrix – http://www.ncsu.edu/tutorial_center/writespeak/download/Synthesis.pdf

Use your results to...

1. Describe current knowledge about your research topic

2. Support the need for and significance of new research

3. Explain research findings4. Describe the quality of a body of research*

*Fink, A. (2005). Conducting Research Literature Reviews. London: Sage.

Level of Evidence Pyramid

Qualitative Studies

Trip searches both

Recap• Research lit reviews are: systematic, explicit and reproducible• Appropriate research questions are narrow... But not too narrow!• Break your question into concepts• Identify synonyms and subject headings for each concept • Combine synonym searches with OR • Combine concept searches with AND• Apply practical and methodological screens• Send search results to a citation manager• Move to the next source or database retaining as much of your

strategy as possible• Use your lit review to summarize knowledge, assess research and

support new research initiatives

QUESTIONS