Systematic review: Difference between revisions
| Line 37: | Line 37: | ||
Regarding non-randomized studies, the Cochrane states, "Judging a result to be at a particular level of risk of bias for an individual domain implies that the result has an overall risk of bias at least this severe."<ref>Sterne JAC, Hernán MA, McAleenan A, Reeves BC, Higgins JPT. Chapter 25: Assessing risk of bias in a non-randomized study. In: Higgins JPT, Thomas J, Chandler J, Cumpston M, Li T, Page MJ, Welch VA (editors). Cochrane Handbook for Systematic Reviews of Interventions version 6.4 (updated August 2023). Cochrane, 2023. Available from https://training.cochrane.org/handbook/current/chapter-25#section-25-3-5</ref> | Regarding non-randomized studies, the Cochrane states, "Judging a result to be at a particular level of risk of bias for an individual domain implies that the result has an overall risk of bias at least this severe."<ref>Sterne JAC, Hernán MA, McAleenan A, Reeves BC, Higgins JPT. Chapter 25: Assessing risk of bias in a non-randomized study. In: Higgins JPT, Thomas J, Chandler J, Cumpston M, Li T, Page MJ, Welch VA (editors). Cochrane Handbook for Systematic Reviews of Interventions version 6.4 (updated August 2023). Cochrane, 2023. Available from https://training.cochrane.org/handbook/current/chapter-25#section-25-3-5</ref> | ||
[https://www.gradepro.org/ GRADE] helps assess risk of bias<ref name="pmid21247734">{{cite journal| author=Guyatt GH, Oxman AD, Vist G, Kunz R, Brozek J, Alonso-Coello P | display-authors=etal| title=GRADE guidelines: 4. Rating the quality of evidence--study limitations (risk of bias). | journal=J Clin Epidemiol | year= 2011 | volume= 64 | issue= 4 | pages= 407-15 | pmid=21247734 | doi=10.1016/j.jclinepi.2010.07.017 | pmc= | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=21247734 }} </ref><ref>What is GRADE? BMJ Best Practice: Evidence-based medicine (EBM) toolkit. https://bestpractice.bmj.com/info/us/toolkit/learn-ebm/what-is-grade/</ref>. | |||
[https://www.gradepro.org/ GRADE] helps assess risk of bias<ref name="pmid21247734">{{cite journal| author=Guyatt GH, Oxman AD, Vist G, Kunz R, Brozek J, Alonso-Coello P | display-authors=etal| title=GRADE guidelines: 4. Rating the quality of evidence--study limitations (risk of bias). | journal=J Clin Epidemiol | year= 2011 | volume= 64 | issue= 4 | pages= 407-15 | pmid=21247734 | doi=10.1016/j.jclinepi.2010.07.017 | pmc= | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=21247734 }} </ref>. | |||
==Characteristics== | ==Characteristics== | ||
Revision as of 20:32, 5 January 2024
|
WikiDoc Resources for Systematic review |
|
Articles |
|---|
|
Most recent articles on Systematic review Most cited articles on Systematic review |
|
Media |
|
Powerpoint slides on Systematic review |
|
Evidence Based Medicine |
|
Cochrane Collaboration on Systematic review |
|
Clinical Trials |
|
Ongoing Trials on Systematic review at Clinical Trials.gov Trial results on Systematic review Clinical Trials on Systematic review at Google
|
|
Guidelines / Policies / Govt |
|
US National Guidelines Clearinghouse on Systematic review NICE Guidance on Systematic review
|
|
Books |
|
News |
|
Commentary |
|
Definitions |
|
Patient Resources / Community |
|
Patient resources on Systematic review Discussion groups on Systematic review Patient Handouts on Systematic review Directions to Hospitals Treating Systematic review Risk calculators and risk factors for Systematic review
|
|
Healthcare Provider Resources |
|
Causes & Risk Factors for Systematic review |
|
Continuing Medical Education (CME) |
|
International |
|
|
|
Business |
|
Experimental / Informatics |
Clinical trials should begin and end with systematic reviews of relevant evidence
All health researchers should begin their training by preparing at least one systematic review
Overview
A systematic review is a literature review focused on a single question which tries to identify, appraise, select and synthesize all high quality research evidence relevant to that question. Systematic reviews are generally regarded as the highest level of medical evidence by evidence-based medicine professionals. An understanding of systematic reviews and how to implement them in practice is becoming mandatory for all professionals involved in the delivery of health care.
Reporting standards
Background
In 1987, Mulrow assessed review articles for the following criteria[1]:
- Was the specific purpose of the review stated?
- Were sources and methods of the citation search identified?
- Inclusion criteria: "Were explicit guidelines provided that determined the material included in and excluded from the review"?
- Validity assessment of included articles: "Was a methodologic validity assessment of material in the review performed"?
- Was the information systematically integrated with explication of data limitations and inconsistencies?
- Was the information integrated and weighted or pooled metrically?
- Was a summary of pertinent findings provided?
- Were specific directives for new research initiatives proposed?
QUORUM and PRISMA
The history of the QUORUM and PRISMA reporting standards are summarized[2].
- QUORUM (QUality Of Reporting Of Meta-analyses) was started in 1999 to recommend reporting standards for meta-analyses of randomized controlled trials.
- PRISMA (Preferred Reporting Items of Systematic reviews and Meta-Analyses) was started in 2009
Risk of bias assessment
Regarding randomized controlled trials, the Cochrane states, "The overall risk of bias for the result is the least favourable assessment across the domains of bias. Both the proposed domain-level and overall risk-of-bias judgements can be overridden by the review authors, with justification." and provides a table for "reaching an overall risk-of-bias judgement for a specific outcome"[3] Regarding non-randomized studies, the Cochrane states, "Judging a result to be at a particular level of risk of bias for an individual domain implies that the result has an overall risk of bias at least this severe."[4]
GRADE helps assess risk of bias[5][6].
Characteristics
A systematic review is a summary of healthcare research that uses explicit methods to perform a thorough literature search and critical appraisal of individual studies to identify the valid and applicable evidence.
Meta-analyses
Systematic reviews often, but not always, use appropriate techniques (meta-analysis) to combine these valid studies, or at least use grading of the levels of evidence depending on the methodology used.
Meta-narrative reviews
While many systematic reviews are based on an explicit quantitative meta-analysis of available data, there are also qualitative reviews which nonetheless adhere to the standards for gathering, analyzing and reporting evidence. The RAMESES reporting standards guide the creation of these reviews[7].
Living systematic reviews
Living systematic reviews have been described:
- https://bestpractice.bmj.com/info/us/toolkit/discuss-ebm/living-systematic-reviews-towards-real-time-evidence-for-health-care-decision-making/
- https://community.cochrane.org/review-production/production-resources/living-systematic-reviews
- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6556985/
Cochrane collaboration
Many healthcare journals now publish systematic reviews, but the best-known source is the Cochrane Collaboration, a group of over 6,000 specialists in health care who systematically review randomised trials of the effects of treatments and, when appropriate, the results of other research. Cochrane reviews are published in the Cochrane Database of Systematic Reviews section of the Cochrane Library, which to date (February 2007) contains 2,893 complete reviews and 1,646 protocols.
The Cochrane Group provides a handbook for systematic reviewers of interventions, where they suggest that each systematic review should contain the following main sections:
- Background
- Objectives
- Methods of the review
- Results
- Conclusion and discussion
There are seven steps for preparing and maintaining a systematic review, as outlined in the Cochrane Handbook:
- Formulating a problem
- Locating and selecting studies
- Critical appraisal of studies
- Collecting data
- Analyzing and presenting results
- Interpreting results
- Improving and updating reviews
Strengths and weaknesses
While systematic reviews are regarded as the strongest form of medical evidence, a review of 300 studies found that not all systematic reviews were equally reliable, and that their reporting could be improved by a universally agreed upon set of standards and guidelines.[8]
A further study by the same group found that of 100 guidelines reviewed, 4% required updating within a year, and 11% after 2 years; this figure was higher in rapidly-changing fields of medicine, especially cardiovascular medicine.[9] 7% of systematic reviews needed updating at the time of publication. [9]
Teaching how to conduct systematic reviews may help teach research skills[10].
See also
References
- ↑ Mulrow CD (1987). "The medical review article: state of the science". Ann Intern Med. 106 (3): 485–8. doi:10.7326/0003-4819-106-3-485. PMID 3813259.
- ↑ Anonymous. History & Development of PRISMA. Available at http://prisma-statement.org/PRISMAStatement/HistoryAndDevelopment
- ↑ Sterne JAC, Hernán MA, McAleenan A, Reeves BC, Higgins JPT. Chapter 25: Assessing risk of bias in a non-randomized study. In: Higgins JPT, Thomas J, Chandler J, Cumpston M, Li T, Page MJ, Welch VA (editors). Cochrane Handbook for Systematic Reviews of Interventions version 6.4 (updated August 2023). Cochrane, 2023. Available at https://training.cochrane.org/handbook/current/chapter-08#section-8-2-4
- ↑ Sterne JAC, Hernán MA, McAleenan A, Reeves BC, Higgins JPT. Chapter 25: Assessing risk of bias in a non-randomized study. In: Higgins JPT, Thomas J, Chandler J, Cumpston M, Li T, Page MJ, Welch VA (editors). Cochrane Handbook for Systematic Reviews of Interventions version 6.4 (updated August 2023). Cochrane, 2023. Available from https://training.cochrane.org/handbook/current/chapter-25#section-25-3-5
- ↑ Guyatt GH, Oxman AD, Vist G, Kunz R, Brozek J, Alonso-Coello P; et al. (2011). "GRADE guidelines: 4. Rating the quality of evidence--study limitations (risk of bias)". J Clin Epidemiol. 64 (4): 407–15. doi:10.1016/j.jclinepi.2010.07.017. PMID 21247734.
- ↑ What is GRADE? BMJ Best Practice: Evidence-based medicine (EBM) toolkit. https://bestpractice.bmj.com/info/us/toolkit/learn-ebm/what-is-grade/
- ↑ Wong G, Greenhalgh T, Westhorp G, Buckingham J, Pawson R (2013). "RAMESES publication standards: meta-narrative reviews". BMC Med. 11: 20. doi:10.1186/1741-7015-11-20. PMC 3558334. PMID 23360661.
- ↑ Moher D, Tetzlaff J, Tricco AC, Sampson M, Altman DG (2007). "Epidemiology and reporting characteristics of systematic reviews". PLoS Med. 4 (3): e78. doi:10.1371/journal.pmed.0040078. PMID 17388659.
- ↑ 9.0 9.1 Shojania KG, Sampson M, Ansari MT, Ji J, Doucette S, Moher D (2007). "How quickly do systematic reviews go out of date? A survival analysis". Ann. Intern. Med. 147 (4): 224–33. PMID 17638714.
- ↑ Himelhoch S, Edwards S, Ehrenreich M, Luber MP (September 2015). "Teaching Lifelong Research Skills in Residency: Implementation and Outcome of a Systematic Review and Meta-Analysis Course". J Grad Med Educ. 7 (3): 445–50. doi:10.4300/JGME-D-14-00505.1. PMC 4597958. PMID 26457153.
External links
- University of York (March 2001), Undertaking systematic reviews of research on effectiveness:CRD's guidance for those carrying out or commissioning reviews. CRD Report 4 (2nd edition). Retrieved 2007-06-27
- Cochrane Collaboration
- MeSH: Review Literature - articles about the systemic review process
- MeSH: Review [Publication Type] - limit search results to systemic reviews
- PubMed search: "Review Literature"[MAJR]