Literature Reviews in the Health Science

After your initial search but before you implement the final search strategy you need to determine your inclusion and exclusion criteria for selecting your articles. These will include the refinements you used as filters but will also include other elements that you aren't available as filters.

Inclusion criteria are the elements of an article that must be present in order for it to be eligible for inclusion in a literature review.  
Some examples are:

• Included studies must have compared certain treatments
• Included studies must be experimental
• Included studies must have been published in the last 5 years

Exclusion criteria are the elements of an article that disqualify the study from inclusion in a literature review.  Some examples are:

• Study used an observational design
• Study used a qualitative methodology
• Study was published more than 5 years ago
• Study was published in a language other than English

(courtesy https://guides.library.vcu.edu/health-sciences-lit-review/selection-criteria)

Your protocol is a conceptual description of every stage in your research process. It must explain your research in a way that makes it reproducible by future research teams.
Protocols are used for all systematic reviews (meta-analysis) and reviews using a systemic method. You can use a standard protocol or use these as a framework for the one you develop. Protocols are always created before evaluating and selecting the literature. 

• EQUATOR Network - Library of research reporting guidelines by study type or specialty 
• IOM Standards for Systematic Reviews: Standard 3.4: Document the search
• PRISMA website - PRISMA Checklist
• Methods Guide for Effectiveness and Comparative Effectiveness Reviews
• Cochrane Handbook for Systematic Reviews of Interventions - See Part 2, Chapter 6.6: Documenting and reporting the search process

For systematic reviews and meta-analysis only - PROSPERO is the National Institute of Health Research system for registering review protocols. Their form includes 22 mandatory fields and 18 optional fields which will help you to explain every aspect of your research plan. Sample application with required fields. 

DOWNLOAD a protocol template  - (University of Warwick)