Saturday, November 29, 2014

"the standards for the evidence are often low and tainted by commercial or personal interests"

In the eyes of doctors and the public, evidence-based medicine is the gold standard of clinic practice. If it’s based on evidence from trials and laboratories, it must be right.

However, evidence-based medicine has its critics, as a bilious outbreak of comment and letters in the BMJ demonstrated recently. Early last month a Glasgow GP, Des Spence, said that the system of EBM had been corrupted. “If we don’t tackle the flaws of EBM there will be a disaster, but I fear it will take a disaster before anyone will listen,” he wrote. 

How could anyone fault the notion of treatment based on scientifically validated evidence? No one. But the critics of EBM argue heatedly that the standards for the evidence are often low and tainted by commercial or personal interests. Dr Spence accuses drug companies of
manipulating the gold standard to their own benefit. “Today EBM is a loaded gun at clinicians’ heads. ‘You better do as the evidence says,’ it hisses, leaving no room for discretion or judgment. EBM is now the problem, fueling overdiagnosis and overtreatment.”

A number of letters pointed out that, while EBM had its flaws, doctors still need to exercise their clinical judgement. They write the prescriptions, not the drug companies.
Dr Spence was supported by Dr Miran Epstein, a medical ethicist at The London School of Medicine. He writes that “EBM “does not regard polluted information, whether it involves misconduct or not, as a sufficient condition for rendering disclosure inadequate. Thus, it lets informed consent degenerate into a legal fiction and the principle of autonomy into a cynical farce. Worst of all, it is perfectly ethical: being the codified expression of the collective conscience of our medicine, it naturally purports to be moral.” 

And he was supported by lawyer and ethicist Charles Foster, writing in the Practical Ethics blog. He believes that the editors of journals need the help of a regulator to sift the wheat from the chaff. “Journals can’t do it all. We need a cynical, skeptical, well-funded, well-staffed and ideologically very left-wing regulator. With huge teeth.” 

Evidence-based medicine comes under attack
by Michael Cook | 8 Feb 2014 |
tags: 
commercializationevidence-based medicine

http://www.bioedge.org/index.php/bioethics/bioethics_article/10841 

Thursday, November 27, 2014

Publication bias distorting evidence base, systematic reviews and clinical guidelines

For decades, the systematic review of published randomised controlled trials has been considered the gold standard in medical research, and this was what the original Cochrane reviewers did.
By combining data from all published trials on a particular subject, researchers are able to see effects in much larger numbers of people than would typically be included in a single trial, in theory making their conclusions more powerful.
In theory. The problem in reality is a small thing called publication bias.
Some trials are simply more likely to be published than others, potentially skewing the results of this kind of meta-analysis.
MJA InSIght, Monday, 14 October, 2013

Jane McCredie: Sharing evidence