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What does Evidence-based actually mean? or Where have all the sceptics gone?

25 Feb, 16 | by BMJ Clinical Evidence

Caroline Blaine

By Caroline Blaine

Commonly held opinions of Evidence-Based Medicine (EBM) include:

“Surely all medicine practised today is evidence-based.”


“EBM just means blindly following guideline recommendations and trial results. It allows no place for professionalism, it is too rigid, and it does not “fit” the patient in front of me.”

Neither of these assumptions is true. The first one denies—against all evidence—that a problem exists, and the second is far from what the founders of EBM described.

Looking back to the publications on EBM from the early 1990’s onwards gives a perspective of the serious issues they were tackling, and the desire to make this fun, as well as easy to understand and adopt. Re-reading the original papers, it is disappointing to reflect on how little the paradigm has shifted. more…

GATE – a Graphic Appraisal Tool for Epidemiological studies

12 Nov, 15 | by BMJ Clinical Evidence

Rod Jackson head shotBy Rod Jackson

The Graphic Appraisal Tool for Epidemiological studies (GATE) is a simple, easily remembered toolkit to help you critically appraise epidemiological studies that includes one picture, two equations and three acronyms. GATE uses a picture of a triangle, circle, square and two arrows to represent the generic structure of epidemiological studies. We call this picture ‘the GATE frame.’ All common epidemiological study designs, from randomised controlled trials to case-control studies, can be illustrated using a GATE frame. While the GATE approach to critical appraisal covers the same ground as other critical appraisal guides, its point of difference is its generic graphic framework that emphasises the similarities between all study designs. With GATE, your goal is to ‘hang’ a study on the GATE frame as follows: more…

Topical treatments for seborrhoeic dermatitis of the scalp – need for more evidence

3 Sep, 15 | by BMJ Clinical Evidence

Diphoorn, JanoukBy Janouk Diphoorn and Luigi Naldi

Seborrhoeic dermatitis is one of the most common skin conditions. It occurs in 3 to 10% of the population. The scalp is one of the areas most frequently involved. For people with seborrhoeic dermatitis of the scalp it can be very distressing since there is itching and visible scaling, which can cause social embarrassment.

As the condition tends to relapse after treatment, it is important to consider maintenance treatment after clearance. Nowadays the most used treatment in clinical practice is ketoconazole, which is thought to inhibit the Malessezia furfur yeasts considered to play a role in the development of this condition. For the acute phase corticosteroids are often added to inhibit the inflammatory reaction.

In general there is limited evidence available on the treatment of seborrhoeic dermatitis of the scalp with topical agents. This is unfortunate as it is such a common condition. Only ketoconazole and ciclopirox were studied in multiple RCT’s that met the inclusion criteria for our recent BMJ Clinical Evidence systematic overview. For other topical treatments such as bifonazole, selenium sulfide, tar shampoo and corticosteroids the evidence was much sparser. more…

Fetal cell or stem cell derived treatment for Parkinson´s disease

4 Jun, 15 | by BMJ Clinical Evidence

by Arnar Astradsson and Tipu Z. Aziz

Arnar Astradsson pictureTipu Aziz.crop

Parkinson’s disease (PD) is a neurodegenerative disorder characterized by the selective loss of nigrostriatal dopaminergic neurons which results in the cardinal symptoms of tremor, rigidity, bradykinesia and postural instability. The mainstay of therapy has been pharmacological substitution of dopamine using levodopa. However, after years of pharmacological therapy eventually the benefits may wear off and side effects such as dyskinesias may develop. Deep brain stimulation of the pallidum or subthalamic nucleus is also being used, which effectively controls the motor symptoms of Parkinson’s disease. As an alternative to pharmacological therapy or electrostimulation, cell-based therapies that reconstruct the nigrostriatal pathways have been developed with the transplantation of fetal ventral midbrain neurons into the striatum of PD patients. more…

A gap in the evidence – What is the role of surgery in the patient with severe (secondary) Raynaud’s phenomenon?

21 May, 15 | by BMJ Clinical Evidence

by Ariane Herrick and Lindsay Muir




People with Raynaud’s phenomenon secondary to an underlying disease or condition (the best researched one being systemic sclerosis) can progress to irreversible tissue injury with ulceration and/or critical ischaemia and gangrene. Although there has been increasing interest in recent years in identifying new drug therapies for severe Raynaud’s phenomenon with randomised controlled trials (RCTs) of, for example, phosphodiesterase inhibitors and endothelin receptor antagonists, the recent BMJ Clinical Evidence overview identified no RCTs of any of the surgical procedures that  have been advocated for advanced peripheral vascular disease. more…

Trigeminal neuralgia – gaps in evidence

14 May, 15 | by BMJ Clinical Evidence

by Joanna M. Zakrzewska and Mark E. Linskey

Trigem imageTrigeminal neuralgia is a rare condition that causes excruciating intermittent short-lasting, usually unilateral facial pain especially provoked by light touch.
Although the criteria for diagnosis appear to be clear cut, there have been no case control studies to validate them, and there is no cohort data on progression of the disorder. This is especially important as—while the disorder is generally progressive over time—in more than 50% of cases this progression is interspersed with unpredictable remissions that can last 6 months or longer. more…

A brief introduction to the concept of Evidence-Based Research

7 May, 15 | by BMJ Clinical Evidence


by Hans Lund

The scientific ideal
On 15th of February 1676, in a letter to his colleague (and rival) Robert Hooke, Sir Isaac Newton wrote the following well-known sentence: “If I have seen farther it is by standing on the shoulders of giants”. Newton referred to influential scientists before him such as Copernicus, Galilei and Kepler and emphasised one of the fundamental aspects of science – science is cumulative with each new discovery dependent on previous knowledge. more…

Addressing gaps in evidence

9 Apr, 15 | by BMJ Clinical Evidence

?????????????????????????????????????????????????????????????????????????Evidence-based medicine (EBM) is an approach that—in addition to clinical experience and patient preferences—takes into account existing research evidence to draw conclusions on the best approach for the care of individual patients. It is a key tool for clinical decision making as the need to balance research, new tests and treatments, and available resources with clinical experience and patient requirements continues to be an important focus in healthcare. more…

How much health evidence is there in the world?

2 Apr, 15 | by BMJ Clinical Evidence

by Gabriel Rada

Picture Gabriel Rada
Thirty five years ago, Archie Cochrane reproached the medical profession for not having managed to organise a “critical summary, by specialty or subspecialty, adapted periodically, of all relevant randomised controlled trials”.
Systematic reviews were invented to deal with this problem, thus enabling what we call evidence based medicine, and their number has being steadily growing. more…

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