Grades and Levels of Evidence: Difference between revisions
Tyler Shultz (talk | contribs) No edit summary |
Tyler Shultz (talk | contribs) No edit summary |
||
Line 100: | Line 100: | ||
<br> | <br> | ||
<div class="researchbox"> | |||
{| cellspacing="1" cellpadding="1" border="1" style="width: 411px; height: 168px;" | |||
|- | |||
| colspan="2" | '''Grades of Recommendation''' | |||
| '''Strength of Evidence''' | |||
|- | |||
| '''A ''' | |||
| Strong Evidence | |||
| A prepoderance of level I and/or level II studies support the recommendation. This must include at least 1 level I study. | |||
|- | |||
| '''B''' | |||
| Moderate Evidence | |||
| A single high-quality randomized controlled trial or a preponderance of level II studies support the recommendation | |||
|- | |||
| '''C''' | |||
| Weak Evidence | |||
| A single level II study or a preponderance of level III and IV studies including statements of consensus by content experts support the recommendation | |||
|- | |||
| '''D''' | |||
| Conflicting Evidence | |||
| Higher-quality studies conducted on this topic disagree with respect to thier conclusions. The recommendation is based on these conflicting studies | |||
|- | |||
| '''E''' | |||
| Theoretical/ Foundational Evidence | |||
| A preponderance of evidence from animal or cadaver studies, from conceptual models/principles, or from basic sciences/bench research support this conclusion | |||
|- | |||
| '''F''' | |||
| Expert Opinion | |||
| Best practice based on the clinical experience of the guidelines development team | |||
|} | |||
<div class="researchbox"></div> | |||
== Recent Related Research (from [http://www.ncbi.nlm.nih.gov/pubmed/ Pubmed]) == | == Recent Related Research (from [http://www.ncbi.nlm.nih.gov/pubmed/ Pubmed]) == | ||
<rss>link|charset=UTF-8|short|max=10</rss> </div> | <rss>link|charset=UTF-8|short|max=10</rss> </div> |
Revision as of 17:49, 8 June 2009
Original Editor - Tyler Shultz
Lead Editors - Your name will be added here if you are a lead editor on this page. Read more.
Discussion & Background[edit | edit source]
Levels of Evidence[1]
[edit | edit source]
Level |
Therapy/Prevetion, Aetiology/Harm |
Prognosis |
Diagnosis |
Differential Diagnosis |
Economic and Descision Analysis |
1A |
SR (with homogeneity) of RCTs |
SR (with homogeneity) of inception cohort studies; CDR validated in different populations |
SR (with homogeneity) of Level 1 diagnostic studies; CDR with 1b studies from different clinical centres |
SR (with homogeneity) of prospective cohort studies |
SR (with homogeneity) of Level 1 economic studies |
1B |
Individual RCT (with narrow Confidence Interval) |
Individual inception cohort study with > 80% follow-up; CDR validated in a single population |
Validating cohort study with good reference standards; or CDR tested within one clinical centre |
Prospective cohort study with good follow-up |
Analysis based on clinically sensible costs or alternatives; systematic review(s) of the evidence; and including multi-way sensitivity analyses |
1C |
All or none series |
All or none case serires |
Absoulute SpPins and SnNouts |
All or none case series |
Absolute better-value or worse-value analyses |
2A |
SR (with homogeneity) of cohort studies |
SR (with homogeneity) of either retrospective cohort studies or untreated control groups in RCTs |
SR (with homogeneity) of Level >2 diagnostic studies |
SR (with homogeneity) of 2b and better studies |
SR (with homogeneity) of Level >2 economic studies |
2B |
Individual cohort study (including low quality RCT; e.g., <80% follow-up) |
Retrospective cohort study or follow-up of untreated control patients in an RCT; Derivation of CDR or validated on split-sample only |
Exploratory cohort study with good reference standards; CDR after derivation, or validated only on split-sample or databases |
Retrospective cohort study, or poor follow-up |
Analysis based on clinically sensible costs or alternatives; limited review(s) of the evidence, or single studies; and including multi-way sensitivity analyses |
2C |
"Outcomes" Research; Ecological studies |
"Outcomes" Research |
Etiological Studies |
Audit or outcomes research | |
3A |
SR (with homogeneity) of case-control studies |
SR (with homogeneity) of 3b and better studies |
SR (with homogeneity) of 3b and better studies |
SR (with homogeneity) of 3b and better studies | |
3B |
Individual Case-Control Study |
Non-consecutive study; or without consistently applied reference standards |
Non-consecutive cohort study, or very limited population |
Analysis based on limited alternatives or costs, poor quality estimates of data, but including sensitivity analyses incorporating clinically sensible variations. | |
4 |
Case-series (and poor quality cohort and case-control studies) |
Case-series (and poor quality prognostic cohort studies) |
Case-control study, poor or non-independent reference standard |
Case-series or superseded reference standards |
Analysis with no sensitivity analysis |
5 |
Expert opinion without explicit critical appraisal, or based on physiology, bench research or "first principles" |
Expert opinion without explicit critical appraisal, or based on physiology, bench research or "first principles" |
Expert opinion without explicit critical appraisal, or based on physiology, bench research or "first principles" |
Expert opinion without explicit critical appraisal, or based on physiology, bench research or "first principles" |
Expert opinion without explicit critical appraisal, or based on physiology, bench research or "first principles" |
Produced by Bob Phillips, Chris Ball, Dave Sackett, Doug Badenoch, Sharon Straus, Brian Haynes, Martin Dawes since November 1998. Updated by Jeremy Howick March 2009.
Download a pdf of this chart here.
Grades of Evidence[2][edit | edit source]
Grades of Recommendation | Strength of Evidence | |
A | Strong Evidence | A prepoderance of level I and/or level II studies support the recommendation. This must include at least 1 level I study. |
B | Moderate Evidence | A single high-quality randomized controlled trial or a preponderance of level II studies support the recommendation |
C | Weak Evidence | A single level II study or a preponderance of level III and IV studies including statements of consensus by content experts support the recommendation |
D | Conflicting Evidence | Higher-quality studies conducted on this topic disagree with respect to thier conclusions. The recommendation is based on these conflicting studies |
E | Theoretical/ Foundational Evidence | A preponderance of evidence from animal or cadaver studies, from conceptual models/principles, or from basic sciences/bench research support this conclusion |
F | Expert Opinion | Best practice based on the clinical experience of the guidelines development team |
Recent Related Research (from Pubmed)[edit | edit source]
Extension:RSS -- Error: Not a valid URL: link|charset=UTF-8|short|max=10
Recent Related Research (from Pubmed)[edit | edit source]
Extension:RSS -- Error: Not a valid URL: Feed goes here!!|charset=UTF-8|short|max=10
References[edit | edit source]
- ↑ Levels of Evidence. 2009. Available at: http://www.cebm.net/index.aspx?o=1025 [Accessed June 8, 2009].
- ↑ Guyatt GH, Sackett DL, Sinclair JC, et al. Users' guides to the medical literature. IX. A method for grading health care recommendations. Evidence-Based Medicine Working Group. JAMA. 1995;274(22):1800-1804.