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Mental Health and Learning Disabilities: PICO & Systematic Reviews

Useful Shelfmarks for Systematic Reviews

Useful Journal Articles

LSBU Powerpoint Presentation on Systematic Reviews

What are Systematic Reviews by Cochrane

Explanation of Systematic Reviews

What is a Systematic Review?

A systematic review:

  • Answers a focused (usually clinical) question
  • Uses a comprehensive search strategy that another researcher can easily reproduce to retrieve the same results
  • Identifies ALL applicable studies (published and unpublished)
  • Evaluates all results using an agreed criteria for inclusion and quality
  • Brings together the findings in an unbiased way and presents a balanced summary
  • Typically run by at least two researchers, but often involves large teams
  • Can take months or even years to complete

Difference between a Systematic Review & a Systematic Literature Review?

Systematic Review Systematic Literature Review
Collates ALL relevant studies that answer a specific question Critically appraises studies and literature on a topic
Comprehensive search of published and unpublished material Thorough search of published material
Has a detailed protocol (see examples on Cochrane) Includes a detailed search strategy that can be replicated
Involves a team of researchers to avoid bias Usually produced by a single person therefore subject to bias
Takes months or even years to produce Takes weeks or months to produce

About the Cochrane Library

The Cochrane Library is a collection of databases that contain different types of high-quality, independent evidence to inform healthcare decision-making.

The Cochrane Database of Systematic Reviews (CDSR) is the leading resource for systematic reviews in health care. CDSR is built throughout the month, with new and updated reviews and protocols being continuously published when ready.

The Cochrane Central Register of Controlled Trials (CENTRAL) is a highly concentrated source of reports of randomized and quasi-randomized controlled trials. They do not contain the full text of the article. CENTRAL is published monthly.

Cochrane Clinical Answers (CCAs) provide a readable, digestible, clinically-focused entry point to rigorous research from Cochrane Reviews. 

More information about the Databases can be found on About the Cochrane Library webpage

About the Campbell Collaboration

The Campbell Collaboration is an international research network that produces systematic reviews of the effects of social interventions in

  • Crime & Justice 
  • Disability 
  • Education 
  • International Development 
  • Knowledge Translation and Implementation 
  • Nutrition
  • Social Welfare 

The Campbell Collaboration's Information Retrieval Methods Group has published a guide to information retrieval for systematic reviews: "Searching for studies: A guide to information retrieval for Campbell Systematic Reviews". This is based on the searching chapter within the Cochrane Handbook but adapted to suit the different subject area.

What is PICO?

PICO is a technique used to help make the process of finding an answer to a clinical question easier, by identifying appropriate keywords that can be used to conduct a literature search. 

Examples of questions that it may be used for (not a conclusive list):

Treatment - establishing whether a particular treatment would benefit a patient

Diagnostic: confirm or exclude a diagnosis

Prognosis: estimate the likely course of a medical condition

Prevention: reduce the chances of disease by identifying risk factors 


Gerrish, K. and Lacey, A. (eds.)  (2010) The research process in nursing. 6th ed. Chichester: Wiley-Blackwell.