These criteria help you decide which pieces of evidence (for example, which primary research studies) will/will not be included in your work. Using specific criteria will help make sure your final review is as unbiased, transparent and ethical as possible.
To establish your criteria you need to define each aspect of your question to clarify what you are focusing on, and consider if there are any variations you also wish to explore. This is where using frameworks like PICO help:
Example: Alternatives to drugs for controlling headaches in children.
Using the PICO structure you clarify what aspects you are most interested in. Here are some examples to consider:
|
PICO Element |
Key concept |
Questions for developing inclusion and exclusion criteria |
|---|---|---|
|
Patient/Population/Problem |
Children |
A specific age group? Teenagers and adolescents? |
|
Interventions |
Alternatives to drugs |
What alternatives are there? Complementary therapies? Alternative medicines? Changes in lifestyle? All three? If you decide to focus on 'complementary therapies' do you want to examine all therapies or a specific therapy like holistic therapy? |
|
Comparison |
Drugs |
All drugs that treat headaches, or a group of drugs, or a specific drug? |
|
Outcomes |
Headaches |
All types of headaches, or a specific type such as tension headaches or migraines? |
The aspects of the topic you decide to focus on are the Inclusion criteria.
The aspects you don't wish to include are the Exclusion criteria.