Deer, B. (2011). How the case against the MMR vaccine was fixed. BMJ, 342:c5347.
Causality is the cause-and-effect relationship between two variables. Correlation implies a relationship between two variables without a direct cause and effect link. Correlation may imply causation, but it is not enough to make a direct link between two variables.
Due to a sudden spike in autism diagnoses in the 1980s and 1990s, people started searching for a reason behind its emergence in their communities. Public awareness exploded upon the release of Rain Man, a 1988 film based on the true story of a man living with autism. People were afraid of the syndrome waiting to steal their babies in plain sight. When Andrew Wakefield, John Walker-Smith, and eleven other professionals from the Royal Free medical school published their study on the causal link between MMR vaccines and autism in The Lancet in 1998 (Deer, 2011, p. 1), the public was more than willing to accept their findings as fact. When people are afraid, they are more easily swayed.
Dr. Leo Kanner, Johns Hopkins University professor and leading authority on autism, published a paper in 1943 describing symptoms now associated with autism. He speculated that autism was rare based on the following:
- Limited study: he had seen fewer than 150 children with symptoms.
- Selective criteria: he discouraged diagnosing autism in children with seizures.
- Subjective generalization: he attributed autism to “cold and unaffectionate parents”.
Kanner’s limited criteria remained the gold standard until Drs. Lorna Wing and Judith Gould published their paper on autism in 1979 using broadened criteria to diagnose autism. Soon after their clinical trials, more doctors around the world started diagnosing children with autism.
Andrew Wakefield’s study was quantitative research based on false data. Quantitative research focuses on the numbers and what is happening. Unfortunately, Andrew Wakefield’s data was built on fallacies and inconsistencies.
Unbeknownst to the editors of the scientific publication, attorney Richard Barr had retained Wakefield two years before the study was published to prove the absolute causality of MMR vaccines on autism and “bowel-brain” syndrome. Barr needed the data to build a lawsuit against the manufacturers of the vaccines.
Andrew Wakefield was “not a pediatrician. He was a former trainee gastrointestinal surgeon with a non-clinical medical school contract” (Deer, 2011, p. 7). He did not have the expertise to diagnose children. He also identified the syndrome “before any of the children were investigated”, (Deer, 2011, p.2).
He made assumptions based on correlation, not causation. Correlation analysis measures the strength of the relationship between variables. Causation reveals the influence of one event or process on another event or process. It reveals a direct connection between the two, often described in “if/then” statements.
Wakefield could not prove causal inference, due to the absence of the temporal sequence and concomitant variation. Due to the inconsistencies and false data of the time/order of the symptoms and the vaccines, he could not establish a temporal sequence. Several children in his study had autistic and “bowel-brain” symptoms before receiving the MMR vaccines.
Concomitant variation refers to changes in the cause that result in changes in the effect. Observing the concomitant variation of different patients, namely child 3 with serious bowel trouble and a suspicious connection to MMR (Deer, 2011, p. 10), could have revealed the lack of causality in the study.
The 1998 paper was debunked and retracted in 2010 but left considerable damage in its wake. I remember the vaccine discussions I had with other mothers in 2009 and 2010. Most of them opted to spread out the MMR vaccines or defer them indefinitely out of fear. Today, some of these same mothers have decided against vaccinating their children against COVID-19 for the exact same reason.
Andrew Wakefield authored a fraudulent study on the causality of MMR vaccines on autism based on correlation and false data. How many people now associate vaccines with a negative outcome? How many lives have been lost due to this skepticism?
L2: Demonstrate the ability to assess complex organizational environments and achieve communicative goals.
L4: Apply communication-centered scholarship to strengthen communication effectiveness.
Keywords: vaccine hesitancy, vaccine conspiracy theory, causality, concomitant variation, temporal sequence
