Systematic reviews: The question

• Has the question already been answered?
• What is the purpose of asking this question?
• What will this question add to the existing literature?
• Is it helpful to use a question framework such as PICO or SPIDER? 
• How will concepts in the question be defined? For example:
  • How will adult be defined? What age range is this? 18 to 64? 18 plus? 21 plus?
  • How will diabetes be defined? Does it include type 1, type 2, pre-diabetes?
• Does the question limit to a particular type of study, such as RCTs?
• Does the question involve quantitative, qualitative or mixed method publications? 
• What is in or out of scope? What will the inclusion and exclusion criteria be?
• Does the question involve a specific timeframe (limiting by date)? If so, why?

It is not essential to follow a question framework, but it may be useful. Remember that every concept in a framework is not always replicated in a search strategy, as it can make the search too tight. 

Some question frameworks:

• PICO - Patient | Intervention | Comparison | Outcome
• PECO – Population | Environment | Comparison | Outcome
• SPIDER - Sample | Phenomenon of Interest | Design | Evaluation | Research type
• SPICE - Setting | Perspective | Intervention | Comparison | Evaluation

Learn more:

• Framing a research question - University of Maryland Library
• Systematic Reviews for Health: 1. Formulate the Research Question - University of Tasmania Library

Library staff can assist with searching for existing review papers. Please note that this is a quick search where strategies are not provided. It is not a structured search for the systematic review itself. 

• Request a standard literature search (SVHM staff only - please explain you are looking for existing review papers only)

Many systematic reviews don't make it over the finish line. These are some of the reasons we have experienced as co-authors:

Review team cannot agree on details or keeps expanding the question

The problem:

• Can create a "fluffy" topic that is too wide, badly defined and understood, and which changes.
• Even slight shifts in the question are likely to require new search strategies and starting over.
• Consumes a great deal of time as each version of the question is explored.
• As the review becomes too difficult the team may lose interest in proceeding.

How to avoid:

• Don't start work on the review proper (including searches) until consensus has been reached. 
• Make a decision and stick to it.
• Write and register a protocol. Lock it in!

The question has already been answered before you publish

The problem:

• Another systematic review on the same topic may be discovered during the searches - either initially or during updates.
• If there are long delays (especially with screening) another review might be published first.

How to avoid:

• Carry out an initial scoping search for existing reviews before writing a protocol.
• Search PROSPERO for an existing protocol.
• Ensure that the team is committed to screening in a timely way to avoid delays.
• If another review is discovered towards the end of the process, consider whether there is anything new to add that is likely to be accepted by a journal. All may not be lost!