Friday, November 12, 2010

Don't blame accutane, the data sure as heck don't...

Before you make fun of me, "don't" in the title of this post is correct as the word "data" is the plural of "datum". Don't get me started on trying to figure out what, if anything, people mean when they use the phrase "data point". 

As hopefully now I have established, the purpose of this blog is to examine critically the ways in which statistics in the media are reported inaccurately (deliberately or out of ignorance) to the detriment of all of us. In today's Huffington Post, (I can feel a collective eye roll coming), via the Associated Press, we have a doozy of a headline.

"Acne Problems, Drug Treatments May Raise Suicide Risk

MARIA CHENG | 11/12/10 11:56 AM | AP"

A new study by Swedish researchers examined acne sufferers who took accutane (isotretinoin) to see if they had an increased incidence of suicide vs. the general population (remember increased incidence is NOT sufficient to imply causality).  They speculate (but DO NOT conclude) that it is not the drug, but rather the depression created form a painful and highly visible condition. The reason that they are required to speculate is that they could NOT reject the null hypothesis that there is "no relationship between suicide attempts and accutane." Rather than continuing to make a feeble conclusion that the data weren't (insert lame excuse here), they dealt honestly with the reality that until new evidence comes along, they cannot rely on the explanation that accutane wasn't more likely the CAUSE of any difference in the rate of suicide attempts between two populations than random chance.  The reason they couldn't was,
"Experts found the number of suicide attempts increased between about one and three years before the start of the treatment, though that increase was not statistically significant. The highest risk compared with the general population appeared to be within six months of the start of treatment. "

Since the headline is partially "Drug Treatments May Raise Suicide Risk", I have to wonder what gives? 
The author obtained a quote form another "expert." This doctor claims that all patients undergoing accutane therapy should be monitored for signs of depression. What we have here is one of the signs of propaganda I mentioned in an earlier post, "2.Is the writer supporting the claim with anecdotal quotes from someone unrelated to the research? This is key because the author needs someone else to say what the ethical and scientific method trained researcher won't because it's dishonest."

Really, what we see is a statistically insignificant difference wherein, 1 more person in 2,300 (2 people in 2,300 - which is the difference of 0.04% and 0.09%) may attempt suicide. Naturally this is something that one may take into consideration when deciding if drug therapy for acne is right for them. Perhaps, candidates for treatment may need to be screened for depression prior to and during treatment. But to assume that an otherwise happy, well-adjusted person with acne will double their risk of attempting suicide because they took an acne drug would be illogical and irrational.

One thing that I liked about the researchers was that rather than trying to defend the idea that the drugs WERE somehow linked to suicidal behavior, even though the data said otherwise, was that they actually considered other reasons why this sample may have had even a slightly higher incidence of depression. Turns out, having a painful and visible illness might be enough after all, without blaming "big pharma."

Who knows? The point is the headline is MISLEADING and in order to get to the headline, the writer needed another doctor to cough up a quote.  Watch for my next post about necessary and sufficient conditions and why we need both together in order to draw rational conclusions.

1 comment:

  1. Yahoo has a new title for the same article, "Study: Major acne problem may raise suicide risk". Hmmm, at least it doesn't try to jump on the sue Roche bandwagon.