This principles in this podcast are so darn important for critical appraisal
@youyanggu lack of prior infectious disease knowledge is a feature not a bug.
It allows a dispassionate interpretation of evidence.
Say it w me: **content expertise is over-rated!**
2/
I’m all about Bayes, but the novel-ness of COVID-19, and the fact that it’s a once-in-a-lifetime pandemic, should reduce (or eliminate) any prior beliefs.
I dare say the frequentist-like approach may have been better for Covid.
4/
The other reason to listen to this podcast is to hear how silly the ecological studies cited by CDC are.
Rule 1— never ever use howler-science to promote a public policy like masks or in-person school or anything
Just say we don’t know, but here is our best judgement.
5/
It’s not the 1980s
People can look up stuff.
When they learn that you cite howler science, they are less likely to believe you when you cite good science, such as vaccine trials.
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NEJM published 2 RCTs of #AFib ablation vs AF drugs.
The rub was that the ablation was done EARLY in the course.
Practice had been to try drugs first then do ablation.
EARLY AF and STOP AF studied the procedure early. #AHA20 Thread and my column >>
Both trials used the Medtronic cryoballoon system.
Medtronic participated in funding both trials.
STOP AF was 100% an industry trial. See pic.
Early AF had funding from many other sources
Background -- numerous trials have shown that AF ablation using different techniques (freezing or burning) can reduce AF episodes relative to meds.
In CABANA -- the largest outcome trial, AF ablation reduced AF but had no sig effect on clinical outcomes like stroke or death.
Giving talks in which you don't have a slide deck already made is illuminating. Look what I found out about publication bias>
It was "discovered" in 1979 by Rosenthal content.apa.org/record/1979-27…
How did he do this?
Thread ...
He used a variant of ...sit down for this...the Fragility Index, which we reported on in cardiology ahajournals.org/doi/10.1161/CI…
The criticism was fierce. But I liked it. @ShahzebKhanMD
Here's Rosenthal's explanation
I am no stats person but this looks a lot like a fragility concept applied to all studies.
Thread: To me, the most stunning report from #ESCCongress thus far: RATE-AF trial
Older pts w/ permanent AF + shortness of breath. (there are lots of these pts).
Rate control is crucial
In 2020, most receive beta-blockers.
But BB can cause dyspnea.
What about dig?
Gulp! 1/
Rate-AF randomized these pts to bb vs digoxin. Here is the protocol paper: bmjopen.bmj.com/content/bmjope…
Crucially they looked at quality of life. That's a really important outcome.
The results shocked me. Look at heart rates. Dig isn't supposed to be this good.
Need help from trial methods people. I ran across this amazing paper by @phlegmfighter et al looking at consequences of recommendations in the design and interpretation of Non-inferiority trials. pubmed.ncbi.nlm.nih.gov/28875400/
THEY SUGGEST SYSTEMIC BIASES.
Thread
If you put the new treatment on the left side of the interpretative diagram, there are four ways to make Non-inferiority. Scenarios 1-4. but....
They show that if the convention were to put the active control on the left side of the diagram, make the new treatment the control, you would bias strongly toward the control (thus making NI more difficult to reach). No change in data, just the mirror image here:
Thread coming on one way docs might add value to the #COVID19 crisis: critical appraisal.
I wrote a critique of a flawed study published in a major journal. The study reported on the assoc of anticoagulant use and death in COVID pts. medscape.com/viewarticle/93…
It is an important topic b/c numerous studies have suggested a high rate of clot-related complications in acute #COVID19 illness. it makes sense to consider anti-coagulants...
But anticoagulants come with harms--bleeding. What's more, in non-COVID pts we know that there are actual clots that we are treating. Infection control issues sometimes prevents knowing whether a person w/ #COVID19 actually has clots.