Some definitions:
Original materials on which other research is based.
Usually the first formal appearance of results in the print or electronic literature.
Present information in its original form, neither interpreted nor condensed nor evaluated by other writers.
Are from the time period (for example, something written close to when what it is recording happened is likely to be a primary source.)
Present original thinking, report on discoveries, or share new information.
Some examples:
Scientific journal articles reporting experimental research results
Proceedings of Meetings, Conferences and Symposia.
Technical reports
Dissertations or theses (may also be secondary)
Internet communications on email, listservs, and newsgroups
In science, secondary sources are those which simplify the process of finding and evaluating the primary literature. They tend to be works which repackage, reorganize, reinterpret, summarise, index or otherwise "add value" to the new information reported in the primary literature.
Some definitions:
Describe, interpret, analyze and evaluate the primary sources.
Comment on and discuss the evidence provided by primary sources.
Are works which are one or more steps removed from the event or information they refer to, being written after the fact with the benefit of hindsight.
Some examples:
Dictionaries and encyclopedias
Handbooks and data compilations
Journal articles, particularly in disciplines other than science (may also be primary)
Monographs (other than fiction and autobiography)
Newspaper and popular magazine articles (may also be primary)
Review articles and literature reviews
Textbooks
Primary, Secondary & Tertiary Sources
Written by Ward Saylor & Helen Hooper for Information and Research Support, within the Information Services program of the Academic Support Division at James Cook University, July, 2000.
http://cms.jcu.edu.au/libcomp/assist/guides/azguides/JCUPRD_030412
It can be difficult to tell the difference between original research articles and review articles. You can use this chart to help you.
You can also read the article abstract for clues. If you see phrases such as "we tested" and "in our study, we measured", it will tell you that the article is reporting on original research.
The following chart offers a brief summarization oft the review types featured in this guide along with their perceived strengths and weaknesses. For more, full-fledge explanation, please visit each review's corresponding page within this guide.
| Type | Description | Strengths | Weaknesses |
| Literature Review | Generic term; published materials that offer an examination of recent/current literature. Can cover wide range of topics at various levels of completeness and comprehensiveness | Brings together what has been accomplished without repetition and identifying gaps or omission all within a summation | No set method to ensure completeness or comprehensiveness. Includes high chance of bias |
| Critical Review | Aims to demonstrate that the writer has extensively researched the literature and critically evaluated it for quality. Goes beyond simple description to include a degree of analysis and synthesis. Typically results in the formation of hypothesis or model | Used to look at the entire body of work on a given topic. Can be used to introduce an idea, resolve competing theories, or call for testing on a topic. | Its methods do nor require the same degree of systematicity when compared to other review methodologies. No requirement to present the methods of the search, synthesis, and analysis explicitly. The focus is on the conceptual contribution of the included literature, not on formal quality assessment. Resulting product is a starting point for further evaluation, not an endpoint |
| Integrative Review | Summarizes past empirical or theoretical literature to provide a more comprehensive understanding of a particular phenomenon or healthcare problem; often implemented by nursing research communities |
Commonly includes non-experimental research, such as case studies, observational studies, and meta-analyses, but may also include practice applications, theory, and guidelines. Can help inform healthcare policy and practice |
Combining different types of studies can lead to a lack of thoroughness and an increase in bias. No set method for conducting analysis and synthesis |
| Mapping Review | Map and categorize existing literature from which to commission further reviews and/or primary research by identifying gaps in the literature | Enables contextualization of in-depth systematic review process within broader literature and identification of evidence gaps. Can help determine what is needed to make an informed decision on a topic, or if a subset can be reviewed due to theoretical perspective, population group, or setting of the study |
Time constrained, do not usually included quality assessment, and lack synthesis and analysis of more considered approaches. Studies can be characterized at a broad level which may oversimplify the picture regarding studies and their findings |
| Meta-Analysis | Technique that statistically combines the results of quantitative studies to provide a more precise effect of the results | Utilizes small or inconclusive studies into other studies to aid in forming conclusions that the user would otherwise be unable to do | Cannot be better than its included studies allow. Some have argued that the combination of studies is comparing apples and oranges |
| Overview of Reviews | Specifically refers to the a review compiling evidence from multiple viewpoints into one document. Focuses on broad condition or problem for which there are competing interventions. Highlights reviews that address these interventions and their results | Compiles the evidence of multiple reviews to answer a specific question. Creates a balance between macro-scale reviews and reviews that adopt a micro-focus to examine a specific topic thus becoming hyper-specific | Is dependent upon there already being a narrower sub-section of reviews on the topic |
| Rapid Review | Assessment of what is already known about a policy of practice issue. Uses systematic review methods to search and critically appraise existing research | Designed to be completed quickly by using less systematic search strategies, looking at other reviews but not grey literature | Shortened time frame leads to limited quality assessment which increases the risk of including biased or low quality research |
| Scoping Review | Preliminary assessment of potential size and scope of available research literature. Seeks to identify nature and extent of research evidence | Are used to determine if a full systematic review will be necessary to form a conclusion |
Possesses a higher risk of being biased |
| Systematic Review | Seeks to systematically search for, appraise, and synthesis research evidence, typically adhering to strict guidelines on the conduct of a review | Comprehensive, seeks to include all knowledge, including grey literature, on a given topic | Time-intensive and lengthy process. Strict inclusion/exclusion criteria that can be restrictive and/or hinder wide scale application of methodology when providing conclusions |
| Systematized Review | Review features components of the systematic review process while stopping short of systematic review. Typically conducted for postgraduate work (thesis/dissertation/capstone) | Models the systematic review process and allows the author to demonstrate an awareness of the systematic review process and technical proficiency in the component steps. May form the basis for a more extensive work | The quality assessment and the synthesis are usually less defined, this can lead to bias. Such reviews do possess a greater likelihood of bias than those that adhere more strictly to guidelines on the conduct of systematic reviews |
Grant, Maria J., and Andrew Booth. “A Typology of Reviews: An Analysis of 14 Review Types and Associated Methodologies.” Health Information & Libraries Journal, vol. 26, no. 2, June 2009, pp. 91–108. Wiley Online Library, doi:10.1111/j.1471-1842.2009.00848.x.
