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Evolution of Genomes, Cells and Development: MCB 143: Write Reviews

Selected article indexes, literature reviews, citation evaluation, primary source information

what is

A literature review is a discussion of published information focused on a particular subject area or research question that identifies, appraises, selects and synthesizes research evidence relevant to the question.

Systematic reviews are a type of literature review of evidence-based medicine. Systematic reviews are not limited to medicine and are common in all other sciences where data are collected, published in the literature, and an assessment of methodological quality for a precisely defined subject would be helpful.

When to do

When do researchers conduct literature reviews?
1. To write a review paper
2. Write the introduction / or discussion of a research paper
3. Start a new area of research
4. Write a research proposal.

What is the function of a literature review?
1. Summarize the literature
2. Evaluate the literature
3. Show relationships between difference studies
4. In a research proposal show how published work relates to your work.

Reviews must be:
Accurate: citations correct, findings attributed to authors correct.
Complete: include all important papers -- not every paper on the topic.

Which literature to include?
Articles: most up-to-date but can be 2-5 years old.
Internet Sources: use only referred electronic journals
Conference Proceedings: the latest research but not yet published.
Government & corporate Reports: good for commissioned research
Theses and Dissertations: limit use, researcher may be inexperienced.
Books: may be less up to date, but can be comprehensive and a good starting point.
Annual Reviews


1. Understand what a literature review is a survey of scholarly articles, books and other sources (e.g. dissertations, conference proceedings) relevant to a particular issue, area of research, or theory, providing a description, summary, and critical evaluation of each work. The purpose is to offer an overview of significant literature published on a topic.

2. Components
Similar to primary research, development of the literature review has four stages:

  • Problem formulation—which topic or field is being examined and what are its component issues?
  • Literature search—finding materials relevant to the subject being explored
  • Data evaluation—determining which literature makes a significant contribution to the understanding of the topic
  • Analysis and interpretation—discussing the findings and conclusions of pertinent literature

Literature reviews should include the following elements:

  • An overview of the subject, issue or theory under consideration, along with the objectives of the literature review
  • Division of works under review: (e.g. in support of a particular position, against, or offering alternative theses)
  • Explanation of how each work is similar to and how it varies from the others
  • Conclusion of the best considered in their argument, most convincing of their opinions, and make the greatest contribution to the understanding and development of their area of research

In assessing each piece, consideration should be given to:

  • Provenance—What are the author's credentials? Are the author's arguments supported by evidence (e.g. primary historical material, case studies, narratives, statistics, recent scientific findings)?
  • Objectivity—Is the author's perspective even-handed or prejudicial? Is contrary data considered or is certain pertinent information ignored to prove the author's point?
  • Persuasiveness—Which of the author's theses are most/least convincing?
  • Value—Are the author's arguments and conclusions convincing? Does the work ultimately contribute in any significant way to an understanding of the subject?

3. Definition and Use/Purpose
A literature review may be a chapter of a thesis or dissertation, or may be a self-contained review of writings on a subject. In either case, its purpose is to:

  • Place each work in the context of its contribution to the understanding of the subject under review
  • Describe the relationship of each work to the others under consideration
  • Identify new ways to interpret, and shed light on any gaps in, previous research
  • Resolve conflicts amongst seemingly contradictory previous studies
  • Identify areas of prior scholarship to prevent duplication of effort
  • Point the way forward for further research
  • Place one's original work (in the case of theses or dissertations) in the context of existing literature

The literature review itself, however, does not present new primary scholarship.

Steps to do a literature review

Step 1: Define your research topic and questions
Problems to be addressed by the review should be in clear, structured questions.

Step 2: Identify relevant work
Search multiple resources for studies without language restrictions. Study selection should flow from the review questions and be specified a priori. Reasons for inclusion and exclusion should be recorded.

Step 3: Assess the quality of studies
Study quality assessment is relevant to every step of a review.
Question formulation and study selection criteria should describe the minimum acceptable level of design.

Step 4: Summarize the evidence
Data synthesis consists of study characteristics, quality and effects and the use of statistical methods for exploring differences between studies and combining their effects.

Step 5: Interpret the findings
Be careful of bias. Exploration for heterogeneity should help determine whether the overall summary can be trusted, and, if not, the effects observed in high-quality studies should be used for generating inferences.


1. Trying to read everything - read the most relevant
2. Read but not write: write and write many drafts
3. Not keeping bibliographic information!!
4. Organize your review chronologically - organize by IDEAS>

What questions to lit reviews answer

1. What do we know about the area of inquiry? key concepts, factors, variables
2. What are the relationships between key concepts, factors variables?
3. What are the current theories?
4. What are the inconsistencies and other problems?
5. What need further testing because evidence is lacking, inconclusive, contradictory, limited?
6. What design or methods are faulty?
7. Why study this question further?
8. What conclusion will your work make?

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