Many types of reviews exist in academic literature. This page will explain some of the common types, including literature, systematic, and scoping reviews.

Types of Reviews and Evidence Synthesis

Literature Review

  • A more broad, wide scope type of search with no standardized methodology. 
  • Provide a comprehensive overview of the topic and to highlight significant areas of research. Can also help identify gaps in the research.
  • Can vary in comprehensiveness.
  • No protocol need.

Systematic Review

  • A transparent, reproducible, objective, and comprehensive search of the literature focusing on a well-formulated research question.
  • The goal is to identify, appraise, select, and synthesize high-quality evidence relevant to a specific question.
  • See below for a more detailed description of this type of review.

Meta-Analysis

  • A Systematic review plus a statistical analysis of all the included studies' data.
  • The aim is to synthesize evidence across studies to detect effects, estimate their magnitudes, and analyze the factors influencing those effects.

Scoping Review

  • Uses a systematic type of methodology to address a broader research question.
  • The aim is to look for gaps in the literature, what is available, what is missing or ongoing.
  • Seeks to identify the nature and extent of research evidence and opportunities for evidence synthesis.

Umbrella Review

  • A 'review of reviews'.
  • Uses the findings of reviews relevant to a review question to be compared and contrasted.
  • Tends to define a broader question than is typical of a traditional systematic review. 

Rapid Review

  • A quick Systematic Review.
  • Uses the traditional Systematic Review methodology but uses less resources or ways to cut down on the time frame.
  • Best designed for new or emerging research topics, updates of previous reviews, critical topics, to assess what is already known about a policy or practice.

What Is a Systematic Review?

From the Cochrane Handbook for Systematic Reviews of Interventions:
“A systematic review attempts to collate all the empirical evidence that fits pre-specified eligibility criteria in order to answer a specific research question. It uses explicit, systematic methods that are selected with a view to minimizing bias, thus providing more reliable findings from which conclusions can be drawn and decisions made (Antman et al 1992, Oxman and Guyatt 1993).”

  • Collate all the empirical evidence
    • This will be a large project that yields many citations
    • Identify keywords and controlled vocabulary relevant to retrieve all relevant articles 
    • Search multiple databases and sources of grey literature (content outside of journal articles) to find all evidence available
    • Look through cited and citing references of included articles to make sure your database searches didn’t miss anything
    • Reach out to authors for any additional data, handsearch selected publications or conference proceedings
  • Pre-specified eligibility criteria
    • In advance, decide what will be measured and how
    • Follow protocols including being set on the project, plan, and scope of work
  • Specific research question
    • A good systematic review has a question that is clearly defined and specific
    • Avoid broad question or topic. Broad topics will have too many results to work through
  • Explicit systematic methods
    • Clear and can be recreated
    • Share work, including-
      • Present search strategies for all databases and grey literature sources
      • Describe and defend any filters or limits used
      • Share what database platform was used and any software 
      • Document and report the required information (i.e. PRISMA)
  • Minimizing bias
    • Reduce any all all biases including: language, location, nationality, publication and cost.

Why consider a Systematic Review?

  • They are the point between single studies and synthesized research
  • Considered the core of evidence-based care and usually help inform policy and guidelines
  • Growing in popularity in recent years, but that doesn't mean that every research topic or research question needs to be completed as an SR

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Steps to a Systematic review

Things to consider before you begin

  1. Create a research question and flesh it out
  • Does literature exist on the topic?
  • What are you trying to achieve or answer in this SR?
  • Has an author or group already completed an SR on the topic?
  • Approach topic with a PICO components in mind.
  1. Put together the group of experts that will be part of the team.
  • A true systematic review needs at least 3 content experts. It is best to include a librarian in your team.

Steps

Adapted from the Cochrane Handbook for Systematic Reviews of Interventions

Systematic review steps.jpg

Timeframe

from Cochrane Handbook for Systematic Reviews of Interventions

Month Activity
1-2

Prepare the protocol

3-8 Search for data/studies
2-3 Pilot test of eligibility criteria
3-8 Inclusion assessments
3 Pilot test of risk bias assessment
3-10 Validity assessments
3 Pilot test of data collection
3-10 Collect data
3-10 Data entry
5-11 Follow up of missing information
8-10 Analysis
1-11 Prepare review report
12 Keep the review up to date

Getting more information

Types of reviews Grant, M. J., & Booth, A. (2009). A typology of reviews: An analysis of 14 review types and associated methodologies. Health Information & Libraries Journal, 26(2), 91-108. https://doi.org/10.1111/j.1471-1842.2009.00848.x

Moher, D., Stewart, L., & Shekelle, P. (2015). All in the family: Systematic reviews, rapid reviews, scoping reviews, realist reviews, and more. Systematic Reviews, 4(1), 1-2. https://doi.org/10.1186/s13643-015-0163-7

Sutton, A., Clowes, M., Preston, L., & Booth, A. (2019). Meeting the review family: Exploring review types and associated information retrieval requirements. Health Information & Libraries Journal, 36(3), 202-222. https://doi.org/10.1111/hir.12276

A STEP-BY-STEP GUIDE TO CONDUCTING AN INTEGRATIVE REVIEW

Toronto, C. E., & Remington, R. (2020). A step-by-step guide to conducting an integrative review. Springer.

https://library.villanova.edu/Find/Record/2481911

COMPREHENSIVE SYSTEMATIC REVIEW FOR ADVANCED PRACTICE NURSING

Holly, C., Salmond, S. W., & Saimbert, M. (Eds.) (2022). Comprehensive systematic review for advanced practice nursing (Third edition). Springer Publishing.

https://library.villanova.edu/Find/Record/2833776/

PRINCIPLES AND PRACTICE OF SYSTEMATIC REVIEWS AND META-ANALYSIS

Patole, S. (Ed.). (2021). Principles and practice of systematic reviews and meta-analysis. Springer.

https://library.villanova.edu/Find/Record/2615914

Helpful Tools

Systematic Review Tool Box 

The SR Toolbox is a community-driven, searchable, web-based catalogue of tools that support the systematic review process across multiple domains. Contains free and subscription based resources.

SearchRxiv 

Has been established to support researchers to report, store and share their searches consistently and to enable them to review and re-use existing searches.

CADIMA 

CADIMA is a free web tool facilitating the conduct and assuring for the documentation of systematic reviews, systematic maps and further literature reviews. 

Rayyan 

Rayyan is a free web application for semi-automated screening titles and abstracts.