What is a Systematic Review?
“A systematic review uses systematic and explicit methods to identify, select, critically appraise, and extract and analyze data from relevant research” – Cochrane Handbook
Systematic Review Process Diagram
Welcome to the interactive process map.
This tool was developed by the St. Michael’s hospital KT program. We have a defined and rigorous process for all our systematic reviews.
This process map takes you through the steps to conduct a systematic review. Click on the individual steps for more information about each step.
Develop Research Question using PICOST
• Population of interest
• Intervention to examine
• Outcome of interest
• Study design(s)
• Time limitations
Determine Eligibility Criteria
• Develop a research question based on PICOST
AHRQ series paper 3: identifying, selecting, and refining topics for comparative effectiveness systematic reviews: AHRQ and the effective health-care program. Whitlock EP et al. 2010. J Clin Epidemiol.
Plan Literature Search
• Ask a librarian to develop the search to ensure relevant keywords and search strategies are used for a comprehensive search; peer-review by another librarian
Perform Literature Search
• Search at least two databases, difficult to locate or “grey” literature, hand search key journals, ask experts, and scan reference lists
Starting a Systematic Review
• Identify knowledge gap and research question with knowledge users
• Involve key stakeholders during the review process (i.e. integrated knowledge translation)
Level 1 Screening: Titles and Abstracts
• Pilot test to assess accuracy and usability of eligibility criteria developed for the Level 1 screening process with a small sample of studies
• Screening of all titles and abstracts by two independent reviewers. Conflicts usually resolved by discussion
Level 2 Screening: Full Text Articles
• Pilot test to assess accuracy and usability of eligibility criteria developed for the Level 2 screening process with a small sample of studies
• Screening of all full text articles by two independent reviewers. Conflicts usually resolved by discussion
Develop Data Abstraction Form
• Pilot test the form on a small sample of studies to ensure it captures all relevant information from the studies. Revise forms as necessary
• Two reviewers abstract data independently and assess study quality. Conflicts usually resolved by discussion
Critical Appraisal and Assessment
• Critical appraisal is the assessment of evidence by systematically reviewing its relevance, validity, and results.
Summarize Study and Patient Characteristics
• Use tables and text to describe study and patient characteristics
Synthesize the Results
• Based on your research question and the available data, choose the appropriate method to synthesize your findings
• This may include:
- Network meta-analysis (NMA)
- Individual patient data NMA
- Qualitative synthesis methods
Presentation of Results
• Present, summarize, discuss and contextualize findings
• Use summary tables and figures
• Include background, methods, results, and discussion; may involve key stakeholders/audience
End-of-Review Knowledge Translation
• For example: Conference presentations, Key opinion meetings, Peer-reviewed publications
Systematic Review Protocol Development
Systematic Review Protocol Development based on the PRISMA-P statement
Examples of methodology projects conducted by our team
- Robson, R. C., Pham, B., Hwee, J., Thomas, S. M., Rios, P., Page, M. J., Tricco, A. C. (2019). Few studies exist examining methods for selecting studies, abstracting data, and appraising quality in a systematic review. Journal of Clinical Epidemiology, 106, 121-135. doi: 10.1016/j.jclinepi.2018.10.003.
- Tricco, A. C., Cogo, E., Page, M. J., Polisena, J., Booth, A., Dwan, K., … & Moher, D. (2016). A third of systematic reviews changed or did not specify the primary outcome: A PROSPERO register study. Journal of Clinical Epidemiology, 79, 46-54. doi: 10.1016/j.jclinepi.2016.03.025.
- Tricco, A. C., Straus, S. E., & Moher, D. (2011). How can we improve the interpretation of systematic reviews? BMC Medicine, 9(31). doi: 10.1186/1741-7015-9-31.
Examples of Systematic Reviews conducted by our team
- Ashoor, H. M., Lillie, E., Zarin, W., Pham, B., Khan, P. A., Nincic, V., … & Tricco, A. C. (2017). Effectiveness of different compression-to-ventilation methods for cardiopulmonary resuscitation: A systematic review. Resuscitation, 118, 112-125. doi: 10.1016/j.resuscitation.2017.05.032.
- Tricco, A. C., Soobiah, C., Hui, W., Antony, J., Struchkov, V., Hutton, B., … & Straus, S. E. (2015). Interventions to decrease the risk of adverse cardiac events for patients receiving chemotherapy and serotonin (5-HT3) receptor antagonists: A systematic review. BMC Pharmacology and Toxicology, 16(1). doi: 10.1186/2050-6511-16-1.