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Evidence-based medicine

Living Systematic Reviews: towards real-time evidence for health-care decision-making

12 May, 16 | by BMJ

Mavergames 150x150Elliott_150x150


By Chris Mavergames and Julian Elliott

Systematic reviews aim to provide an accurate summary of available evidence for specific health questions. In practice, an increase in methodological expectations and an increasing deluge of primary studies challenges the ability of many review teams to produce timely, high quality systematic reviews and to keep them up to date. Only a minority of reviews are updated within 2 years and as new research is published in the intervening period, these delays lead to significant inaccuracy. One estimate is that 7% of systematic reviews are inaccurate the day they are published and after two years 23% of reviews that are not updated will present incorrect conclusions.  The difficulties faced by review teams in keeping reviews up to date leads to considerable inaccuracy and to some extent undermines the value created through the use of rigorous methods. more…

Autism Interventions: Ask for the Evidence

5 May, 16 | by BMJ

Michael Fitzpatrick_2_cropBy Michael Fitzpatrick

“There’s so many cures for autism on-line, it’s a wonder anyone still has it”

This wry observation from the father of a five-year-old newly diagnosed with autism in the BBC’s ‘The A Word’ strikes a chord with every parent who has been through this experience. As a GP with an autistic son – now 23 –  I have seen wonder cures, from secretin and facilitated communication to chelation and hyperbaric oxygen therapy, appear and disappear at a bewildering pace over the past two decades.  An internet survey in the USA found parents were using 111 different treatments, including diverse speech and behaviour therapies, medications, diets, vitamins and supplements – on average using seven such ‘interventions’ concurrently.
Given that no specific intervention – beyond behavioural educational programmes – has been shown to be beneficial for children with autism, the vast variety of treatments on offer puts parents who are struggling to cope with the challenges of autism in a difficult position. In the spirit of ‘Ask for the Evidence’, I suggest three simple questions:


The blind leading the blind in the land of risk communication

14 Apr, 16 | by BMJ


Glyn ElwynBy Glyn Elwyn

It is often said that humans are terrible at understanding risk. Maybe so when it comes to ratios and rates – abstract forms of data. But all of us navigate the world by moving, walking or driving – constantly comparing distances, magnitudes and likelihoods, making estimates about the risk of collisions, repeatedly, and accurately. We are actually risk calculators extraordinaire – and we do it all effortlessly, using heuristics, and get it right, most of the time. Our survival depends on it.

Blind leading the blindBut when it comes to health care – we are less confident. When to start a medication? When to have an operation or a test? Plus, we have much less experience to draw on. And less data. Often, no data at all. more…

The Rise of Rapid Reviews

24 Mar, 16 | by BMJ

JRB profile picture v2By Jon Brassey

“Perfect is the enemy of good” Voltaire

Rapid reviews are becoming increasingly commissioned, used and written about. But why is there this, relatively sudden, interest? Putting it bluntly, it’s because the cornerstone of evidence synthesis, the systematic review, is becoming increasingly out of touch with the needs of today’s healthcare systems.

The journal Systematic Reviews recently featured an editorial ‘All in the Family: systematic reviews, rapid reviews, scoping reviews, realist reviews, and more’. In the article they report “It is our view that all of these new forms of reviews are related to systematic reviews, similar to the way that different biological Species within the same Family are related to each other.” Tantalisingly they later raise the issue of the extinction of some methods. Is it a given that systematic reviews, as we know them, deserve to survive? more…

Still no evidence for homeopathy

10 Mar, 16 | by BMJ

Paul GlasziouBy Paul Glasziou

This blog was originally written for thebmj and posted on


When the National Health and Medical Research Council report on homeopathy concluded that “There was no reliable evidence from research in humans that homeopathy was effective for treating the range of health conditions considered” few in conventional medicine were surprised, but the homeopathy community were outraged. As chair of the working party which produced the report I was simply relieved that the arduous journey of sifting and synthesising the evidence was at an end. I had begun the journey with an “I don’t know” attitude, curious about whether this unlikely treatment could ever work. Still, who would have believed that bacteria caused peptic ulcers, or that vaccines for cancers would become routine. So just maybe.…but I lost interest after looking at the 57 systematic reviews (on 68 conditions) which contained 176 individual studies and finding no discernible convincing effects beyond placebo. more…

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

25 Feb, 16 | by BMJ

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…

Dabigatran Reversal

28 Jan, 16 | by BMJ

Ken MilneBy Ken Milne

Case: A 62-year-old woman presents to the emergency department with a history of atrial fibrillation and gastroesophageal reflux. She is on metoprolol 25mg twice daily, dabigatran 150mg twice daily, and omeprazole 20mg once daily. She noted some mild epigastric pain over the last week and had a coffee ground emesis that morning. She arrives via EMS with a blood pressure of 110/60, heart rate of 64bmp and O2 saturation of 97% on room air. You wonder if there is a specific agent that can safely and effectively reverse dabigatran? more…

Where’s the evidence for teaching evidence-based medicine?

17 Dec, 15 | by BMJ

Dragan Ilic photoBy Dragan Ilic

The term evidence-based medicine (EBM) was first coined in the 1990s, with the aim of promoting the greater integration of evidence with clinical experience and patient values in medical decision making. EBM has since blossomed into an inter-disciplinary field, being adopted across medicine, nursing, allied health, health policy, and biomedical and health research. What initially began as EBM, has since evolved into evidence-based practice (EBP), evidence based clinical practice (EBCP) and evidence-based health care (EBHC). The last decade has seen the discipline embedded as a foundation unit across many medical, nursing and health science courses.
As someone who has been involved with the teaching of EBM to medical students for over a decade, I’ve always been curious to identify new strategies that may improve the student learning experience. more…

High Flow Nasal Oxygen

4 Dec, 15 | by BMJ

Ken Milne

By Ken Milne

Case: A 55-year-old woman presents to the emergency department with a 48-hour history of cough, fever and increasing shortness of breath. She has no history of chronic respiratory problems. On examination, she febrile, tachycardic, tachypneic, and her oxygen saturation is 88% despite facemask oxygen. You wonder if you should try out the new high flow nasal oxygen (HFNO) machine? more…

GATE – a Graphic Appraisal Tool for Epidemiological studies

12 Nov, 15 | by BMJ

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…

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