Literature Searching


The aim of this page is to give you the tools to do your own literature search.

A literature review involves researching, reading, analysing, evaluating, and summarising literature (typically journals and articles) about a specific topic. The results of a literature review may be an entire report or article OR may be part of an article, thesis, dissertation, or grant proposal. When starting a research project it is important to see what has been done before, identify gaps and areas for further development. 


Steps to the perfect search:

  1. Formulate your question - Using PICO or similar search concept tool
  2. Identify keywords for each search element
  3. Plan the search strategy
  4. Refine the results
  5. Review the literature
  6. Assess the evidence
Systematic Review Guide

Formulate your question

It can be challenging to formulate the ‘right’ question for your topic, but it’s important that you spend time making sure the question:

  • Is answerable
  • Is specific and focused
  • Has not (recently) been answered by anyone else

Using a search planner helps you formulate your research question and better understand the type of information you are looking for. A good research question is researchable, you don't already know the answer to it, it is reasonable and clearly focused.  Three search concept tools you may find helpful are;

PICO ECLIPSE SPIDER

Reviews of interventions for health

Health service management searches

 Qualitative evidence synthesis

P Patient or population

I Intervention

C Comparator or Control

O Outcomes

E Expectation - what does the search requester want the information for?

C Client Group - who is the service aimed at?

L Location - where is the service sited?

I Impact - what is the change in the service, if any, which is being looked for? What would constitute success? How is this being measured?

P Professionals - who delivered the service?

S Service - for which service are you looking for information? For example, outpatient services, nurse-led clinics, intermediate care.

S Sample

P I Phenomenon of interest

D Design

E Evaluation

R Research type

Example Question: What is the accuracy of clinical tests to diagnose superior labral anterior or posterior lesion in adults? (Mirkovic et al. 2005)

"I work in an aged care facility where urinary tract infections are a common problem. I've heard that cranberry juice can help prevent UTIs. I wonder if there's any evidence for that and whether it might help our patients?"

P      Patients in aged care homes

I       Cranberry juice

C      No intervention (status quo)

O      Prevention of UTIs.

Example Question: How can the discharge procedure from the hospital to the community for people with head injuries be improved?

Example Question:

"What are the experiences of first year university students in using their library?"

S      First year university students

PI     Library use

D      Survey

E      Experiences (of using the Library)

R      Qualitative

Richardson, W.S., Wilson, M.C., Nishikawa, J., & Hayward, R.S. (1995). The well-built clinical question: A key to evidence-based decisions.  ACP Journal Club, 123(3) A12-A12.

Wildrige, V., & Bell, L. 2002. How CLIP became ECLIPSE: a mnemonic to assist in searching for health policy/management information. Health Information & Libraries Journal, 19(2) 113-5.

 Cooke, A., Smith, D., & Booth, A. 2012.  Beyond PICO : The SPIDER Tool for Qualitative Evidence Synthesis. Qualitative Health Research, 22(10) 1435 - 1443. 




Search concept tools for developing research questions

PICO – Reviews of interventions for health  PICO Fillable Form.

ECLIPSE – Health service management searches  ECLIPSE Fillable Form

SPIDER– Qualitative evidence synthesis SPIDER Fillable Form

Identify Keywords

Highlight, underline or circle the keywords or main concepts in your summary. These words can help you build your search strategy.

Authors will use different terminology for the same concept so it's important to think of alternative words for each of your concepts. These can be synonyms, related words, abbreviations, acronyms and other words that are specific to your topic.

  • Keywords - These are terms that were harvested, brainstormed or gathered from a variety of sources. These terms can be searched for in any database or platform that allows searching for textwords. 
  • Synonyms - Authors will often use different terms to describe the same concepts.  It's a good idea to include as many alternative terms, or synonyms in your search. e.g., youth, teenager or adolescent; social media or social networks.
  • Plurals - Include both singular and plural versions of words e.g., policy or policies, child or children.
  • Variant spelling - Consider American and English spellings of words e.g., organisation or organization.
  • Acronyms - Acronyms for organisations or a particular concept may need to be written out in full or use both in your search e.g., WHO or World Health Organization

Use Subject Headings

Subject headings are an organised set of phrases or words used to index content in a database so that it can be efficiently retrieved. These are sometimes referred to as controlled vocabulary, subject terms, subject headings, thesaurus terms, or index terms.

Each bibliographic database has their own specific Subject Headings controlled vocabulary to index the key concepts in articles. The same database may be available across many platforms, but the subject headings stay the same. How Subject Headings are searched and applied will vary depending on the database being searched. The following table shows you the main bibliographic databases with examples of different subject headings used for describing the same search term, for example: low carbohydrate diet.


Subject headings for database use

MeSH browser - The Medical Subject Headings (MeSH) thesaurus is a controlled and hierarchically organised vocabulary produced by the National Library of Medicine. It is used for indexing, cataloguing, and searching of biomedical and health-related information. MeSH includes the subject headings appearing in MEDLINE/PubMed, the NLM Catalogue, and other NLM databases. MeSH browsers helps you search for preferred terms to use as keywords. 

If the database uses a controlled vocabulary, the articles in it are assessed by reviewers, who assign the appropriate term/s to the article. Each term will have a scope note so you can make sure it is appropriate for your particular topic. Not every database uses a controlled vocabulary.

It is important to note that not every article will be assigned a term from a database's controlled vocabulary. For example, the article may be so new to the database that it has not yet been assessed. For this reason, always search subject terms as well as keywords for the most thorough search – especially if you are doing a systematic review.


Text mining

The text mining process uses Natural Language Processing (NLP) to examine large collections of documents, books, articles, websites, emails, survey results and reports. It aids in discovery of new information and helps the research literature search process.

Tools are used to analyse documents and identify facts, relationships, word usage and frequency that would otherwise remain buried in the mass of textual big data.  It can be used during the literature searching process to help build a list of keyword and search terms related to a particular research topic. 

PubMed Reminer
A free tool that queries the PubMed database for further search terms based on your results. It will provide you with analysis in a tabular format showing the frequency of terms and MeSH headings. It will also generate rankings that show the most active journals and authors for the terms you have entered.

JSTOR Text Analyzer
This tool allows you to drag and drop a key full text article (from a gold set for example) to produce additional terms for inclusion in a search strategy. Text Analyser checks the article and identifies its key topics.

Other tools: Ovid Citation Analyzer ;  PubVenn ; MeSH on Demand ; Yale MeSH Analyzer 

Plan your search strategy

Determine which database(s) to search. A database guide is available here.  Library of Search Strategy Resources

Use the following Information search planner to identify major elements of your question and translate natural language terms to subject descriptors, headings, or synonyms.

Boolean operators: are a means of combining search terms to broaden or narrow search results

AND -     narrows a search teenage* and ‘‘drug abuse’’
OR -        broadens a search teenage* or adolescen* or youth* or "young adult’’
NOT-       used to exclude terms from a search  aids not ‘‘hearing aids’’

Phrase searching: Phrase searching narrows a search to show results that contain an exact phrase. This is useful when you want to search for a certain string of words.  This requires terms to be searched in the exact order specified within the quotation marks ‘‘ ‘‘   “global warming” “prescription drugs”

Brackets are used to (group terms together) so they are searched first. Search: (animal OR mammal) AND habitat

Truncation and wildcard searching: Truncation and wildcard searching broadens a search to show results that include words with variant endings or spellings. Find word variations or alternate spellings by adding a truncation symbol  * to the end of terms.       adolescen* will find:  adolescent, adolescents, adolescence

Wildcard searching, using the symbol '?", is useful for words that have slight differences in spelling e.g. 'women' and 'woman', 'organisation' and 'organization'.  Insert the ? to replace the variant letter to retrieve both versions of a word, e.g. wom?n; organi?ation.

Broader and narrower terms: ​Using broader terms can extend your results if you're not getting many results. e.g. social media or mass media.

If you results aren't relevant enough try more specific or narrower terms e.g. Facebook or Twitter or Instagram.

Information Search Planner

Print a version of this information to complete here.

 This information search planner will prompt you to identify particular search concepts and strategies, and systematically record the information sources and material types which are relevant to your research

1. Summarise your topic (be as descriptive as possible – the words listed here can be used when searching databases and other resources) 

 Clinical Scenario:

 

 

 Formulate clinical question in the PICO format

 Population: Male ☐Female ☐Both ☐  Infant☐ Child ☐Adolescent☐ Young Adult☐  Adult☐ Aged ☐Aged, 80 and Over☐
About Condition:

 Intervention:

 Comparison: No intervention ☐Placebo studies ☐Other intervention: 

 Outcome:

 Formulate clinical question in the ECLIPSE format (Evaluating services Health Management & Policy) 

 Expectation:

 Client Group:

 Location:

 Impact:

 Professionals:

 Service:

 Do you wish to restrict your search to: reviews ☐meta-analyses ☐ clinical research ☐randomised control trials ☐ guidelines ☐

 

Example using our search template. For the question: Do intake clinicians at South West Healthcare comply with standards of best practice in suicide risk assessment during intake/admission assessment? 

PICO

MeSH Terms

Synonyms

Keywords

P

Adult; Aged; Aged, 80 and over; Adolescents

 

Elderly, Senior, youth, teenage*, teens

Adults

Australian

Victoria*

I

Practice guideline; guideline; practice guidelines as topic;

Education;

Risk Factors; Risk Assessment;

Diagnostic Tests, Routine

Clinical practice guideline; Training; Benefit-Risk Assessment; Risk; Admission Tests, Hospital; Preadmission Physical Examination; screening tools;

Best practice guideline; policy; procedures; care pathway; patient care plan; Australia 

Assessment tool

suicide risk assessment tools

C (Medical condition)

Suicide

Mental Health

Mental hygiene

 

  

SearchRxiv (search archive) is a resource that allows search strings to be stored online, as it grows it will be a useful bank of search strategies.

Search filters and building tools

Has there been a search filter developed for your area of interest? Ask the Library. Search filters are a search strategy developed by experts to objectively retrieve all possible items e.g. articles on a specific topic from a database.

Search filters:

Building tools:


Keep a systematic log of recorded database searches. 

Hand-searching and snowballing

Hand-searching refers to the process of manually going through the contents of journals, conference proceedings or other sources, and screening for relevant studies. Hand-searching is a useful method to find additional reports of trials and studies that might be missed in a database search. Studies can be missed in database searches because they aren't indexed in the databases you choose to search or there is insufficient descriptive information associated with the record such that your keywords or subject headings fail to find the study.

Citation searching (also called snowballing) builds on an article you have already found and know is relevant to your search. Many databases allow you to follow citations. You can follow research ideas by using reference lists and citations to identify key studies.

  • Looking through reference lists of included studies (backward citation searching)
  • Looking at the "cited by" lists for the included studies (forward citation searching)
  • A search to find all articles by an author or group of authors. (author citation searching)

Refine your results

Check the results, you may need to refine it as you have found some other search terms. Run the search again. You may need to do this run / refine a few times before you are satisfied you have covered all of the search terms, there are no spelling mistakes, nothing has been missed. 

You can now refine your results by adding limiters. Applying limiters to your search will allow you to focus your results to the most pertinent and relevant content. Example: Published date.

Further considerations

  • Any terms to exclude?
  • Any limitations (e.g., timeframe, geographic region, demographics)?
  • What are the main scholarly formats (peer-reviewed articles, conference papers, reports, books, systematic reviews etc…)?
  • What are the main unpublished formats (working papers, government reports, pamphlets, posters, conference posters, blogs etc…) 
  • Is there relevant Grey Literature? Grey Literature
  • What is/are the key Journal(s) relating to my topic?
  • Who are the key authors and/or collaborative teams writing about my topic?
  • Who are the Key organizations and web sites?

 Result:  numbers of hits

  • Are they relevant?
  • Full text found? If not ... follow through with Full Text Finder, InterLibrary Loan, Google Scholar?
  • Will you export/save the citation to Refworks/Endnote?

Example Search:

    Search Strategies (use Boolean Operation, e.g. AND, OR, NOT)

    Databases

    No. of Result

    Example: (Oceanic ancestry group OR Aborigines, Australian OR Australian Race) AND (Health promotion OR health campaigns OR Promotion of health)

    AND (School health promotion OR School health Services)

    Subject Limiter: Health Promotion Location Limiter: Australia

    EBSCO Discovery Service (EDS): MEDLINE complete, CINAHL, Clinical Key, Pro-Quest Nursing, Ovid Nursing

    118












    Review the literature

    Once you have added limiters to your search and run the results, choose and review articles that are most relevant to your question. You may need to run the search across multiple databases.

    If you find an article that is particularly relevant to your search, but not available to you in full text, check with your library to see if they can locate the full text of the article for you. 

    Assess the evidence

    Critical appraisal of the existing research evidence is an essential step in the evidence-based practice process.

    What is critical appraisal?
    Critical appraisal involves examining research evidence to judge its quality based on:

    • Trustworthiness: Can we believe the results that are reported?
    • Value: How valuable is this research given what is already known about the topic?
    • Relevance: How does the evidence relate to the local practice or policy issue identified?
    Critical appraisal skills enhance our ability to determine whether research evidence is free of bias and relevant to our patients/clients, and therefore, whether we should use it in our practice. It is important to remember that not all peer-reviewed research will be relevant or have high levels of trustworthiness and value.

    Critical appraisal also helps us to identify the gaps or shortfalls in the existing research evidence, which is important when developing a research proposal, protocol, or grant application.

    Critical Appraisal Tools

    Joanna Briggs Institute has developed checklists for all of below types of studies, this can be found here.

    Critical Appraisal Skills Programme (CASP) has a set of eight critical appraisal tools are designed to be used when reading research, these include tools for Systematic Reviews, Randomised Controlled Trials, Cohort Studies, Case Control Studies, Economic Evaluations, Diagnostic Studies, Qualitative studies and Clinical Prediction Rule. These are free to download either a version to print and hand fill, or a version to fill in electronically.

    Determine the level of evidence



    Evidence Hierarchy

    Studies defined:

    Meta-Analysis: A systematic review that uses quantitative methods to synthesise and summarise results. 

    Systematic Review: A summary of all available studies on a given topic that uses explicit methods to perform a comprehensive literature search and critical appraisal of individual studies. 

    Systematic reviews and meta-analyses are considered the highest quality of evidence because their study design reduces bias and produces more reliable findings.

    Critically Appraised Topics (CAT): provides a quick and succinct assessment (1-2 pages) of what is known (and not known) in the scientific literature about an intervention or practical issue. A CAT is essentially a shorter and less rigorous version of a systematic review. Because it is less rigorous than a systematic review, a CAT may be less comprehensive and more prone to bias.

    Randomised Controlled Trial: Participants are randomly allocated into experimental or control groups and are followed over time for the variable/ outcomes of interest.

    Cohort Study: Identifies participants who currently have a certain condition or receive a treatment and are followed over time and compared with another group of people not affected by the condition.

    Case Control Study: Identifies participants who have a certain outcome (cases) and participants without that outcome (controls). 

    Case Report/ Case Series: A report on one or more participants with a particular outcome. 

    Filtered Vs Unfiltered Information

    Filtered (secondary) resources appraise the quality of multiple studies and synthesise the findings. They often make recommendations for practice which can be used in clinical decision-making. 

    Unfiltered (primary) resources describe original research. They are often published in peer-reviewed journals however have not undergone additional review beyond that of peer-review. In most cases, unfiltered information is difficult to apply to clinical decision-making. 

    Bias

    When appraising studies, it is important to consider issues related to bias. Bias affects the validity and reliability of research results, which can lead to false conclusions or misinterpretation.

    In quantitative studies, there are many sources and forms of bias that can be introduced in the study design and conduct. Some common examples include; Adherence, Allocation, Attrition, Confounding, Detection, Industry Sponsorship, Language, Positive results, Publication, Racial and Selection bias. You can learn more about each of these on the Catalogue of Bias. 


    Requesting Literature

    Cannot find the article you need request it using our Document Delivery Service.

    Request a Literature Search - South West Healthcare staff may request literature searches for patient care, teaching, professional development, research, policy/protocol development, or management purposes. For staff completing assignments, the Library will assist with search strategy design and database training, but will not provide a literature search service.


    Request a Consultation - with a librarian for further help with your literature searching.

     

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