Hierarchy of Evidence
22 pieces tagged Hierarchy of Evidence.
The Pyramid Schema: The Origins and Impact of Evidence Pyramids
[This paper has been updated in 2026 from the 2022 preprint] Evidence pyramids are amongst the most recognisable artefacts of the Evidence-Based Medicine movement. Yet no study has established the origins of evidence pyramids, or analysed whether they offer any information beyond simple lists or tables. In this paper, I establish the origins of the first evidence pyramid and argue that the pyramidal turn is a retrograde step in evidence appraisal.
[Superseded] The Pyramid Schema: The Origins and Impact of Evidence Pyramids
Evidence pyramids are amongst the most recognisable artefacts of the Evidence-Based Medicine movement. Yet no study has established the origins of evidence pyramids, or analysed whether they offer any information beyond simple lists or tables. In this paper, I establish the origins of the first evidence pyramid and argue that the pyramidal turn is a retrograde step in evidence appraisal.
Higher Orders of Evidence
DALLE 2 offers a far more powerful image generation AI than the popular open access 'Craiyon'/'DALLE Mini' model. How does DALLE 2 compare to DALLE Mini's visions of hierarchies and pyramids of evidence?
Visions of Evidence
How does a machine learning algorithm picture hierarchies of evidence and evidence-based medicine - and what do these visions of evidence remind us of the way we understand, order and assemble the information we use to guide clinical practice?
The origins of evidence pyramids
What was the first evidence pyramid? A deep dive into the murky history of this novel way to present an evidence hierarchy reveals a significantly earlier origin that previously presumed.
On the Global Summit: do critiques of evidence hierarchies favour chiropractic?
The Global Summit systematic review claims that spinal manipulation therapy is not effective in preventing any non-musculoskeletal disorders. But a breakaway group has challenged their findings, in part based on my arguments regarding evidence hierarchies. Are they correct? Does my critique undermine the Global Summit review? If so, does the evidence base favour chiropractic?
195 Hierarchies: A Systematic Database Update
The database of evidence hierarchies has been updated based on a new systematic review of the medical literature, and now contains over 195 hierarchies.
5 years: Hierarchies of Evidence in Evidence-Based Medicine
In the five years since the publication of Hierarchies of Evidence in Evidence-Based Medicine, what has changed and what lessons can philosophers learn?
Are hierarchies history?
Even if the hierarchies of evidence are on their way out in EBM in theory, they could still be enjoying the spotlight in practice.
Random Reflections: Cochrane and the Origins of Hierarchies
In 1972, Archie Cochrane publishedEffectiveness and Efficiency: Random Reflections on Health Services. In a little under 86 pages, Cochrane offers a wide-ranged but succinct delivery of his experience and his philosophy of evidence in clinical practice. It's a fascinating...
A Ghost of Progress - How Hierarchies Become Fixtures
I have written extensively on hierarchies of evidence in evidence-based medicine. The origin story of hierarchies of evidence is a little contentious. Several sources in EBM cite Campbell and Stanley's 1963 classic "Experimental and Quasi-experimental Designs for Research" as...
The Dismal Disease: Temozolomide and the Interaction of Evidence
Evidence interacts. To understand the evidence base for an intervention we must look not only at individual studies, but the relationships between them.
The Authority of Evidence-Based Medicine
In the early part of the 20th century, the philosopher Ludwig Wittgenstein sought to demonstrate that metaphysical claims are meaningless. Statements which couldn’t be proven true in some way—through logic or evidence—weren’t even false, they had no meaning at all. But he ran...
The Positivity Machine: "Evidence-Based Alternative Medicine" and Grades of Recommendation
In his beat-poem Storm, the musician and comedian Tim Minchin lays out an apparent paradox. By his criteria, there can never be evidence-based alternative medicine. As soon as there’s evidence that a treatment works, it joins scientific medicine. Minchin goes on to list...
UBL and Variation
I've argued that information about variation in treatment effects is vital for doctors, patients and regulators alike. This information does not come from RCTs. Nonetheless, we can acquire high-quality, compelling evidence of variation. The case studies I've presented in the...
Hierarchies of Evidence: Database of Hierarchies
Hierarchies of Evidence are a tool employed by many advocates of Evidence-Based Medicine. They are used to appraise evidence from a range of sources, as well as to teach medical students about evidence and evidence appraisal. My PhD thesis concerns the variation in hierarchies defended, and the range of philosophical interpretations of those hierarchies.
An information ordering thing
Randall Monroe of xkcdstarted writing explanations of complex physical phenomena using only the most common 1,000 English words (or the most common 'ten hundred', as he'd have to put it). He recently released a straightforward application which allows writers to check which...
The Exhaustiveness Problem
Hierarchies of evidence can be classified as exhaustive or inexhaustive. A hierarchy is exhaustive if and only if it gives some ranking to any given piece of medical evidence - there's nothing it leaves out. But there's a dilemma which hierarchy authors face: either way,...
Two Dogmas of Evidence Hierarchies
Hierarchies of evidence in Evidence-Based Medicine (EBM) come in many varieties and have been very influential in medical practice and policy since the late 1990s. However, two fundamental problematic assumptions underpin the use of hierarchies of any kind in clinical...
An Honest Mess
Evidence-Based Medicine is an attempt to simplify and streamline a complex reality into a more manageable structure. Reflective EBM proponents know that matters are very complicated. But they understand that practitioners have very limited time (and abilities) to deal with...
Strength of Recommendation - the Rudner Problem
Strength of Recommendation hierarchies such as SORT and GRADE go a step further than your standard hierarchy of evidence. Standard hierarchies tend to rank or rate the evidence provided by a study on a scale of quality, strength or validity. Strength of Recommendation...
The Disunity of Evidence-Based Medicine
Critics and advocates alike have expended much effort defining Evidence-Based Medicine. However, there has been little consensus about what “Evidence-Based Medicine” is. Some authors see ‘EBM’ as something one believes—a view about medicine. Others interpret EBM as something...