I am taking a class on Multimedia as part of my Master of Educational Technology degree program. This week our assignment was to develop a podcast and I decided to make it EBM related (always make your work count twice). I used Audacity, a free audio editor and recorder, to create the podcast. There was a learning curve but I have it mostly figured out. In the past when I created all my YouTube videos I “lectured” off the top of my head. For this assignment I had to write a script first and read from it. This is much better than ad-libbing. I don’t have an verbal tics (like “uhs”) and my cadence is better. I suggest if you do any recordings, even about things you know a lot about, make a script and read it.
Medicine Review in a Few will be a podcast series in which I review what I consider important studies in Internal Medicine. Each episode will review one study and will last less than 10 minutes; hence the “in a few” portion of the title. I think its important to keep information that isn’t interactive and is only processed through one channel fairly short. I personally lose interest and focus with long podcasts. According to data from Stitcher.com the average listener abandons a podcast within 22 minutes.
In Episode 1 I review the ADJUST-PE study. I chose to begin my podcast series with this study because I recently used the information in this study to care for a patient. I wasn’t aware of the findings of this study until one of my residents brought it to my attention. I plan to only review clinically useful studies and will comment on any methodological limitations of the studies that I think the average clinician wouldn’t recognize or know how that limitation impacts the study findings. I think podcasts are a good medium to review studies.
For now, the podcasts will only be posted here but if I keep up with this endeaver I’ll ultimately try to get them on iTunes.
The image I used above is from splitshire.com and requires no attribution. The music used in my podcast is royalty free from Looperman.com.
The current issue of the New England Journal of Medicine contains an important trial- the PEITHO trial. Its important because it tells us what not to do.
In the PEITHO trial patients with intermediate risk pulmonary embolism (right ventricular dysfunction and myocardial injury with no hemodynamic compromise) were randomized to a single weight-based bolus of tenecteplase or placebo. All patients were given unfractionated heparin. Patients were followed for 30 days for the primary outcome of death from any cause or hemodynamic decompensation within 7 days after randomization.
This table shows the efficacy outcomes. Looks promising doesn’t it.
The primary outcome was significantly reduced by 56%. This composite outcome is not a good one though. Patients would not consider death and hemodynamic decompensation equal. Also the pathophysiology of the 2 outcomes can be quite different. The intervention should also have a similar effect on all components of a good composite and there is a greater effect on hemodynamic decompensation than death. Thus, don’t pay attention to the composite but look at the composite’s individual components. Only hemodynamic decompensation was significantly reduced (ARR 3.4%, NNT 30). Don’t get me wrong this is a good thing to reduce.
But with all good can come some bad. This trial teaches that we must pay attention to adverse effects. The table below shows the safety outcomes of the PEITHO trial. Is the benefit worth the risk?
You can see from the table that major extracranial bleeding was increased 5 fold (ARI 5.1%, NNH 20) as was stroke, with most of them being hemorrhagic (ARI 1.8%, NNH 55).
This trial teaches a few important EBM points (I will ignore the clinical points it makes):
- You must always weigh the risks and benefits of every intervention.
- Ignore relative measures of outcomes (in this case the odds ratios) and calculate the absolute effects followed by NNT and NNH. These are much easier to compare.
- Watch out for bad composite endpoints. Always look at individual components of a composite endpoint to see what was affected.