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Systematic reviews

A guide that outlines the process for conducting a systematic review.

Develop your research question

A systematic review is an in-depth attempt to answer a specific, focused question in a methodical way.

Start with a clearly defined, researchable question, that should accurately and succinctly sum up the review's line of inquiry.

A well formulated review question will help determine your inclusion and exclusion criteria, the creation of your search strategy, the collection of data and the presentation of your findings.

It is important to ensure the question:

  • relates to what you really need to know about your topic
  • is answerable, specific and focused
  • should strike a suitable balance between being too broad or too narrow in scope
  • has been formulated with care so as to avoid missing relevant studies or collecting a potentially biased result set

Is the research question justified?

  • Are healthcare providers, consumers, researchers, and policy makers requiring this evidence for their healthcare decisions?
  • Is there a gap in the current literature? The question should be worthy of an answer.
  • Has a similar review been done before?

Types of questions

Question types

To help in focusing the question and determining the most appropriate type of evidence consider the type of question. Is there is a study design (eg. Randomized Controlled Trials, Meta-Analysis) that would provide the best answer.

Is your research question to focus on:

  • Diagnosis : How to select and interpret diagnostic tests
  • Intervention/Therapy : How to select treatments to offer patients that do more good than harm and that are worth the efforts and costs of using them
  • Prediction/Prognosis : How to estimate the patient’s likely clinical course over time and anticipate likely complications of disease
  • Exploration/Etiology : How to identify causes for disease, including genetics


If appropriate, use a framework to help in the development of your research question. A framework will assist in identifying the important concepts in your question.

A good question will combine several concepts. Identifying the relevant concepts is crucial to successful development and execution of your systematic search. Your research question should provide you with a checklist for the main concepts to be included in your search strategy.

PICO framework

Using a framework to aid in the development of a research question can be useful. The more you understand your question the more likely you are to obtain relevant results for your review. There are a number of different frameworks available.

A technique often used in research for formulating a clinical research question is the PICO model. PICO is explored in more detail in this guide. Slightly different versions of this concept are used to search for quantitative and qualitative reviews.

For quantitative reviews-

PICO = Population, Intervention, Comparison, Outcome

Population, Patient or Problem Intervention or Indicator Comparison or Control Outcome

Who or what is the question about?

What is the problem you are looking at?

Is there a specific population you need to focus on?

Describe the most important characteristics of the patient, population or problem.

What treatment or changes are you looking to explore?

What do you want to do with this patient?

What factor may influence the prognosis of the patient?

Is there a comparison treatment to be considered?

The comparison may be with another medication, another form of treatment, or no treatment at all.

Your clinical question does not have to always have a specific comparison. Use comparison if you are comparing multiple interventions. Use a control if you are comparing an intervention to no intervention.

What are you trying to accomplish, measure, improve or affect?

What are you trying to do for the patient? Relieve or eliminate the symptoms? Reduce the number of adverse events? Improve function or test scores?

What results will you consider to determine if, or how well, the intervention is working?

For qualitative reviews-

PICo = Population or Problem, Interest, Context
Population or Problem Interest Context

What are the characteristics of the Population or the Patient?

What is the Problem, condition or disease you are interested in?

Interest relates to a defined event, activity, experience or process

Context is the setting or distinct characteristics


For qualitative evidence-

SPICE = Setting, Perspective, Intervention or Exposure or Interest, Comparison, Evaluation

Setting Perspective Intervention, Exposure or Interest Comparison Evaluation

Setting is the context for the question - where

Perspective is the users, potential users, or stakeholders of the service - for whom

Intervention is the action taken for the users, potential users, or stakeholders - what

Comparison is the alternative actions or outcomes - what else

Evaluation is the result or measurement that will determine the success of the intervention - what result or how well

For qualitative and mixed methods-

SPIDER = Sample, Phenomenon of Interest, Design, Evaluation, Research Type

Sample Phenomenon of Interest Design Evaluation Research Type

Sample size may very if qualitative and quantitative studies

Phenomena of Interest include behaviours, experiences and interventions

Design influences the strength of the study analysis and finding

Evaluation outcomes may include more subjective outcomes - such as views, attitudes, etc.

Research types include qualitative, quantitative or mixed method studies

For health services information-

ECLIPSE = Expectation, Client, Location, Impact, Professionals, Service

Expectation Client Location Impact ProfessionalsType Service

Improvement or information or innovation

At whom the service is aimed

Where is the service located?


Who is involved in providing/improving the service?

For which service are you looking for information?