Saturday, May 29, 2010

Jama Article about shenanigans and a loose tangent on a new vaccine

So of the articles reporting on clinical trials that didn't reach statistical significance 40% contained some "spin".  Spin being a fancy way to say lie.   Distract,  trick, deceive .... Whatever

They say in the comment section of the article (which isn't free online):

Our results are consistent with those of other related studies showing a positive relation between financial ties and favorable conclusions stated in trial reports.   Other studies assessed discrepancies between results and their interpretations in the Conclusions sections.....
The publication process in biomedical research tends to favor statistically significant results and to be responsible for "optimism bias" (ie, unwarranted belief in the efficacy of a new therapy).  Reports of RTCs with statistically significant results for outcomes are published more often and more rapidly than are those of trials with statistically nonsignificant results.  Good evidence exists of selective reporting of statistically significant results for outcomes in published articles.  

So,  not only are clinical trials showing a positive effect from a new med or treatment more likely to be published and published faster than those showing negative effects or lack of benefit but also trials get published spinning a lack of effect into benefit?  

It's not really a surprise then when medications proven to increase suicidal thinking in teens and children get marketed as safe and effective depression treatments.

Of course the same JAMA has an entire section called "from the centers for disease control and prevention".   This issue has basically an Ad for Prevnar 13.    The CDC editorial note points out that "Overall,  rates of IPD have remained stable at 22-25 cases per 100,000 since 2002."

IPD is invasive pneumococcal disease.  It means the bacteria pneumococcus got in the ear fluid, blood, lungs,  spinal fluid.   Prevnar came out in 2000 and wasn't widely available because of production problems for at least 2 years.  If Prevnar made a big impact,  then why didn't the rates drop more?

Oh but the CDC looks at a subgroup for us, children less than 5 years old,  it shows that in 2007 black children had a rate of 35.8 per 100,000 while other races was 30.7 and white children 18.4

Prevnar was famous for how it was going to eliminate the racial disparity of the infectious diseases caused by pneumococcus.

This new vaccine, Prevnar 13,  covers approximately 64% of the serotypes that cause IPD in 2007.  The previous prevnar covered about 80%.   There's no worry about testing the effectiveness of the new vaccine.   They just did some antibody studies and then backpedaled on how they measured success of that when 3 serotype-specific antibodies didn't reach target levels after 3 shots.   After 4 shots one serotype (6) still wasn't reaching the target antibody levels.

Who knows how this will translate to clinical cases of IPD.  MAYBE we will get lucky and drive the rate down further from 22-25 per 100,000.  And maybe we'll get lucky and not cause another serotype like 19A which currently tends to be multidrug resistant and difficult to cure.  And maybe the MRSA spike in children wasn't related to the effects the 1st Prevnar had on the normal nasal flora of children.

I guess we're going to find out as the experiment rolls on.

Unless the 24% uptake of the swine flu shot is any indication of the state of trust in organizations like the CDC.

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