A Statistician Evaluates DeStefano 2004 and Hooker 2014

Update Friday October 3, 2014:  Measles-mumps-rubella vaccination timing and autism among young African American boys: a reanalysis of CDC data has been retracted by Translational Neurodegeneration.  Download Retraction

Here are the summaries of the statistician's findings on the relative strengths and weaknesses of the two papers, which evaluated the same dataset. A summary is here.

My Verdict on the DeStefano Study

The criticism that the study discarded data from African American subjects just doesn’t hold water. No data was discarded. For the subjects who were linked to birth certificates, the researchers performed additional analyses. In this light, I see a careful observational study that assessed the role of potential confounders.

The biggest weakness that I see for this study is that the researchers could not compare subjects who were vaccinated for MMR to those who were not vaccinated at all. The authors wrote that they “lacked an unvaccinated comparison group.” The truth is that the vast majority of kids are vaccinated. Consequently, this study compared the distribution of vaccination ages for case and control children to see if the timing impacted the risk of autism. It didn’t.

My Verdict on the Hooker Study

On the surface, it looks like there might be something to this study. However, there are problems lurking beneath the surface. The two major problems I see with Hooker’s study are:

• The full data set has been sliced and diced into a small, biased sample.
• Low birth weight is an uncontrolled, confounding variable

Please read the whole post. I have elided several paragraphs

Thanks to the tiny sample and the uncontrolled confounding variable, Hooker’s results are both imprecise and biased. Consequently, my personal opinion is that Hooker’s results have no scientific value at all.

So. No scandal, no controversy, so no "whistleblower"

About the author of the two posts linked above

I’m Jim Frost and I came to Minitab with a background in a wide variety of academic research. My role was the “data/stat guy” on research projects that ranged from osteoporosis prevention to quantitative studies of online user behavior. Essentially, my job was to design the appropriate research conditions, accurately generate a vast sea of measurements, and then pull out patterns and meanings from it.

Now at Minitab, I am a technical writer who helps people use our software to gain insights from their own data, whether they’re working in quality improvement, academic research, or another field entirely. I’ll be writing about various experiences and practical tidbits that I’ve learned along the way that may help you in your own research endeavors.

The two papers under discussion

1. DeStefano, Frank, Tanya Karapurkar Bhasin, William W. Thompson, Marshalyn Yeargin-Allsopp, and Coleen Boyle, Age at First Measles-Mumps-Rubella Vaccination in Children with Autism and School-Matched Control Subjects: A Population-Based Study in Metropolitan Atlanta, Pediatrics, 2004;113;259

2. Hooker, Brian S., Measles-mumps-rubella vaccination timing and autism among young African American boys: a reanalysis of CDC data, Translational Neurodegeneration 2014, 3:16

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