Skip to Main Content

Systematic Reviews: Systematic Review Process

Profile Photo
Jenessa McElfresh
Jenessa McElfresh, MLIS, AHIP
Systematic Review Service Coordinator
Senior Research & Learning Services Librarian
Associate Professor

The University of Tennessee Health Science Center
Health Sciences Library
877 Madison Avenue, 2nd Floor
Memphis, TN 38163

Steps and Timeline

The first step in the systematic review process is to understand the methods, documentation requirements, and timeline necessary to conduct a quality systematic review. If you have not conducted a systematic review before, additional training may be necessary to establish adequate understanding of these methods among all members of the review team. 
Please register and attend the "So You Think You Want to Do a Systematic Review?" workshop before starting your review. Register here for future sessions:

Steps in the Systematic Review Process

The systematic review process, with or without a meta-analysis, has many stages. Some aspects of the process can be accomplished simultaneously, but many will require the full review team's contributions before moving forward. The following infographic details 24 steps to the systematic review and meta-analysis process:

The steps to a systematic review (and meta-analysis) include:

1. Define research question

2. Establish review team

3. Define the search strategy

4. Define selection criteria

5. Design data collection form

6. Write the protocol and register the review

7. Run the search strategy in multiple databases

8. Collect all abstracts and references in a file

9. Eliminate duplicates

10. Have at least 2 reviewers screen titles and abstracts.

11. Collect, compare, and select for retrieval

12. Retrieve full text and apply selection criteria

13. Contact experts

14. Search for additional references

15. Make the final selection list and complete flow chart

16. Apply data collection form (in pairs)

17. Evaluate study quality and risk of bias

18. Prepare database for analysis

19. Conduct descriptive analysis

20. To meta-analyze or not?

21. Exploration of heterogeneity

22. Check reporting bias

23. Check the quality of the evidence

24. Update, report, and submit for publication

Muka T, Glisic M, Milic J, et al. A 24-step guide on how to design, conduct, and successfully publish a systematic review and meta-analysis in medical research. Eur J Epidemiol. 2020;35(1):49-60. doi:10.1007/s10654-019-00576-5

Sample Systematic Review Timeline

According to the Cochrane Handbook, systematic reviews can take 12-18 months to complete. While it may be tempting to estimate a quicker turnaround, rarely do systematic reviews take less than 12 months to complete.

Months Systematic Review Activity
1-2 Preparation of protocol
3-8 Searches for published and unpublished studies
2-3 Pilot test of eligibility criteria
3-8 Inclusion assessments/Screening
3 Pilot test of Risk of Bias assessment
3-10 Validity assessments
3 Pilot test of data collection
3-10 Data collection
3-10 Data entry
5-11 Follow up of missing information
8-10 Analysis
1-11 Preparation of review report/manuscript
12+ Keeping the review up to date

If you are working against an upcoming deadline, please consult with a librarian on other types of evidence synthesis that may be more appropriate to your needs.