The Literature Review in the Masters Dissertation

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The Literature Review in the Masters Dissertation

• Roberta Sammut

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The role of research reviews

• What is research?
• The systematic investigation to develop
  theories, establish evidence and solve problems
  (Gough et al 2012 p.1)
• Research can focus on
• The creation of new knowledge through primary
  studies
• Creation of knowledge on the basis of previous
  research
• Knowledge should be cumulative (Oakley 2012)

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If I have seen further it is by standing on the
shoulders of giants

• Isaac Newton

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Why are reviews needed

• Research information is like small jigsaw puzzle
  pieces in a box, where there are several
  pictures, several duplicates and several missing
  pieces (Sheldon 1998)
• Individual studies use different methods, are of
  different quality and may present contradictory
  findings
• We cannot give too much importance to one
  individual study

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Why do you need to carry out a literature review?

• Needed for identifying
• Areas of uncertainty
• Where reality may be different to what is
  believed
• Where more research is needed
• How research in the area has been carried out
  strengths and limitations
• The main theories and issues on your topic and
  critique of these

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What distinguishes a good quality literature
review?

• Appropriate breadth and depth
• Rigour and consistency
• Clarity and brevity
• Effective analysis and synthesis
• Use of the literature to justify
• The particular approach to the topic
• The selection of methods
• That your research contributes something new

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Changing expectations at a postgraduate level

• What is expected of a literature review at
  undergraduate level
• Familiarity with a topic
• Skills to be able to carry out a search on the
  subject
• Knowledge on appropriate referencing style and an
  ability to create accurate bibliography
• The ability to summarise key ideas and some
  critical awareness

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Changing expectations at a postgraduate level
(Hart 2007)

• The content of the literature review at
  undergraduate level
• Descriptive and focused on the topic
• Includes the main current papers on the topic
• Analyses the papers on the topic in terms of
  different arguments presented and different
  results

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The expectations at Masters level (Hart 2007)

• An increase in the scope, breadth and depth of
  the literature search
• Application of relevant literature from across
  other disciplines
• Competence in reading research

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The literature review of the Masters dissertation
(Hart 2007)

• The literature review is a major component of
  your dissertation
• Analytical evaluating current ideas on the
  topic
• Summative providing a comprehensive overview of
  what is known, what the gaps are
• Covers methodological issues in relation to
  different research techniques
• Includes discussion of theoretical issues
  relevant to the study

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Your literature review in context

• Your thesis must form a coherent whole
• Your literature review should be clearly linked
  to
• Your justification for carrying out the study
• Your aims and objectives
• Your choice of research design
• The methods used to collect data
• Your discussion of the results
• Your conclusions and recommendations

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Starting out what type of review is appropriate
to your work?

• Traditional Review (Gough 2004)
• Journalistic Review (Greenhalgh 1997)
• Narrative Review (Macdonald 2003)
• Usually broader in focus
• Do not address specific question
• Not necessarily comprehensive in literature
  included
• Do not state reasons for inclusion of papers
• Not structured in approach to searching for
  literature and evaluation of quality
• Systematic Review
• the shift in emphasis from the art of writing a
  review to the science of reviewing the evidence
  (Milne and Chambers 1993)

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Famous example of possible different outcomes for
systematic vs. traditional reviews (Petticrew and
Roberts 2006)

• Linus Pauling (1974) Well-known physician and
  Nobel prize laureate
• Carried out review on effect of Vitamin C on
  prevention of colds
• Conclusions
• High dose of Vit C prevents colds
• People should consume 100 times dose of Vitamin C
  than currently being consumed

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Famous example of possible different outcomes for
systematic vs. traditional reviews (Petticrew and
Roberts 2006)

• Douglas et al (2004)
• Systematic review of papers published during the
  time of Paulings review
• Conclusions
• High doses of Vitamin C do not prevent colds
• Can reduce the duration of the cold by a few days
• Pauling did not include 15 relevant articles

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What is a systematic review?

• A review of research literature using systematic
  and explicit, accountable methods (Gough 2012)
• The key characteristics of a systematic review
  are
• Rigor use of systematic methods to answer set
  research question
• Transparency every step is described nothing
  left to readers imagination
• Replicability a second researcher should arrive
  at the same conclusions (Oakley 2012)

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Features of systematic reviews Rigor (Oakley
2012)

• The methods used are designed to ensure rigor in
  the process being used and are predetermined
• Comprehensiveness in the search used to avoid
  excluding relevant research e.g. grey literature
  which could lead to publication bias
• Specific criteria for the inclusion or exclusion
  of studies to avoid leaving out unfavourable
  results
• Use of more than one researcher to search
  literature, decide on inclusion and exclusion of
  studies, appraise studies
• Conclusions are based on the most rigorous studies

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Features of systematic reviews Transparency
(Oakley 2012)

• Systematic reviews must be clear about
• The question the review is designed to answer
• The suitability of the methods chosen
• How the studies were identified
• Why some studies were included and others not
• How judgements were made about the value of
  particular studies in answering the research
  questions
• The conclusions which are reached in relation to
  policy and practice

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Features of systematic reviews Replicability
(Oakley 2012)

• A systematic review should provide a clear
  explanation of all steps taken in the review
  process
• This should allow another researcher to repeat
  the study
• If the review was carried out rigorously, then
  the results of the second review should be the
  same
• Because procedures used are described, the review
  can be updated

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Diversity of systematic reviews

• A systematic review is a secondary research study
• Questions and methods used in systematic reviews
  reflect those of the primary research studies
• Share the same theoretical assumptions
• Share the same approach

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The key steps of a systematic review (Gough 2012)

• Review initiation Formation of review team
  engagement of stakeholders
• Preparation of a protocol review question,
  conceptual framework and methodology
• Search strategy search and screen literature on
  the basis of eligibility criteria
• Mapping identifying and describing relevant
  research papers
• Appraising critically critiquing the research
  papers using systematic methods (quality
  appraisal criteria)
• Synthesis Putting together the results of the
  review into a coherent whole, creating something
  new (using conceptual framework and quality
  judgements)
• Using reviews (interpret and communicate findings
  with stakeholders)
• All decisions/methods used are explained and
  justified

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One species many breeds

• Systematic reviews may differ on the basis of
  the
• Nature of the research question (Oakley 2012)
• What we want to find out
• What works
• What people want
• What people consider to be appropriate
• The breadth and depth of the research question
• E.g. What is known about the barriers to and
  facilitators of healthy eating and physical
  activity in young people? vs.
• Is CBT more effective than Health Education in
  producing weight loss in young people between 14
  and 16 years of age?

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Step 2 develop a search strategy

• Clearly identify your review question
• PICO framework
• Population (P),
• Intervention (I) or Exposure (E),
• Comparison (C),
• Outcomes (O),
• Time (T)
• SPICE framework
• Setting where?
• Perspective for whom?
• Intervention what?
• Comparison compared with what?
• Evaluation with what result?

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Step 2 Develop a search strategy

• Identify the relevant databases e.g. CINAHL,
  MedLine, PsychInfo, AgeLine etc.
• Consider the advantages/disadvantages of running
  combined searches
• Identify the keywords which you should use to
  access relevant research papers use thesaurus,
  MeSH terms
• Plan out Boolean phrases, truncation and wild
  cards
• Identify any limiters to your search with
  justification

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Step 3 Develop inclusion/exclusion criteria

• Your review should not include every possible
  paper on your topic
• The papers you include should be directly
  relevant
• Develop inclusion/exclusion criteria on the basis
  of your review question

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Step 4 Develop review management tools

• Keep track of what you are doing on a daily
  basis use a diary
• Use bibliographic software/files on
  databases/excel sheets to keep track of articles
  you exclude with reasons for exclusion
• Develop an information extraction sheet to
  consistently extract the same type of data from
  each paper

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Step 5 Use the PRISMA flowchart
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Step 6 Appraise your studies

• Weight of evidence framework (Gough 2007). Three
  dimensions
• Quality of execution of the study soundness
• Appropriateness of the study design and analysis
  for addressing the research question
• How well matched the study is to the focus of the
  review

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Step 6 Appraise your studies

• Use a Checklist or scale to systematically
  examine main methodological aspects of each study
• Less likely that methodological problems will be
  missed
• More than one checklist may be needed if mixed
  methods are used
• Multitude of appraisal tools available
• Downs and Black randomized and nonrandomized
  studies
• Cowley comparative studies
• Newcastle-Ottawa Scale nonrandomised studies
• Critical Appraisal Skills Programme
• There may not be a suitable checklist available
  you may need to adapt a checklist or develop a
  new one

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Step 6 Appraise your studies

• When choosing an appraisal tool consider
• Checklist chosen must be suitable for design of
  studies to be included in the review
• Whether the appraisal tool has been previously
  tested or not for validity and reliability
• You may need to use more than one appraisal tools
  if mixed methods are included

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Step 7 Decide on how you are going to use the
information from the appraisal

• As a threshold to include/exclude studies
• Weight the studies qualitatively, when
  summarizing the results e.g. high, intermediate,
  low quality
• Weight the studies quantitatively - low scoring
  studies contribute less to the final summary
  effect size estimate
• Describe the quality and relevance of each study
  for the reader to arrive at own conclusions
• Carry out a sensitivity analysis effect of
  including/excluding studies of lower quality on
  the results
• Recommendations for future research in terms of
  methods

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Step 7 Writing up

• Prepare a plan of your review
• Introduction
• History of the topic including assumptions and
  definitions from other researchers
• Theoretical background
• Address each of your research objectives by
  summarising research
• Conclusion
• Identify how the data you extracted will be
  synthesised
• Meta analysis
• Narrative synthesis

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Questions to ask yourself when writing up (Hart
2007, p. 14)
How have approaches to these questions increased
our understanding and knowledge?
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In summary key issues for success

• Perseverance and diligence!
• Justification for the topic of your research and
  your choice of approach
• Avoid communicating personal opinions and views
  and dont present facts without sufficient
  evidence
• Learn how to reference properly invest in a
  training programme on the use of bibliographic
  software
• Learn how to use search databases
• Befriend your librarian!
• Keep records of your ongoing work to prevent
  panic later on!
• Be charitable to others work whilst at the same
  time evaluating it!
• Remember there is no such thing as a perfect
  review!

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Recommended Reading List

• Bettany-Saltikov, J.B. (2012) How to do a
  systematic literature review in nursing. Open
  University Press, England
• Gough, D., Olivers, S. and Thomas, J. (2012) An
  introduction to systematic reviews. Sage, London
• Greenhalgh, T. (2010) 4th ed. How to read a paper
  Wiley-Blackwell, Oxford
• Hart C. (2007) Doing a literature review
  releasing the social science research
  imagination. Sage, London
• Hart C. (2001) Doing a literature search. Sage,
  London
• Petticrew, M. and Roberts H. (2006) Systematic
  reviews in the social sciences Blackwell
  publishing, U.S.A.
• Rudestam, K.E. and Newton R.R. (2007) 3rd ed.
  Surviving your dissertation Sage, London