METHODS. Children who were enrolled in an efficacy trial of pertussis vaccines in 1992–1993 were contacted in 2003. Two groups of children were identified, according to thimerosal content in vaccines assigned randomly in the first year of life (cumulative ethylmercury intake of 62.5 or 137.5 µg)
From reading that excerpt you should understand that there were two groups that differed in their level of exposure to thimerosal.
Now, keep that in mind while I digress for a moment. Apparently Dr. Lewis R. First, the new editor of Pediatrics, is writing a blog to summarize the current issue of the journal. This is a good thing since increasing distribution of scientific research makes us all more educated.
If we look at his summary of the February issue you will see what he wrote about the above article :
Finally, we get to the heart of the immunization controversy with a study by Tozzi et al. on whether or not thimerosal can influence neuropsychological performance ten years after immunization in infancy (475-482). You’ll be reassured that the results show essentially no differences between groups who did or did not get thimerosal in their vaccines—and you’ll want to know this information when talking with parents of your patients about the safety and benefits of vaccines.
This passage makes me wonder if he actually read the article in question. If you look at the abstract it is very clear what the groups are, so what gives?
I first saw the discrepancy noted in an entry on the Age of Autism blog by David Kirby. Go read the full post, it is interesting exchange. The day after the post on Age of Autism, Dr. First posted a correction to his blog clarifying his position, for which I have to commend him. From the series on e-mail of Age of Autism it did not initially look like he was going to.
The question is what to make of all of this. I would have thought that the editor of Pediatrics would have been more familiar with the contents of an article, especially if he was writing a summary of it. So what I am left with is either that it was an honest mistake or, more likely, he took the someone else's spin on the study and ran with it.
Now, you may ask why any of this matters.
Consider if you are the normal pediatrician who is very busy doing their job. If you did not have a particular interest in this topic you would pick up the news reports that yet another study shows no link between thimerosal and autism. You might pick up the short summary from the editor of the journal who you would assume would know of what they are writing. Chances are you would not read the study itself let alone the abstract. So you would be left with the impression that this study showed something that it did not.
If you are a normal parent the situation is worse. At best you will see the headline and maybe, if you really care about the issue, you may read some other blog posts giving the white washed version of the study. You will never read the abstract of the study let alone the study itself.
So, does this really matter in the end? Does this sort of misinformation do any harm? I think it does.